Stability and Control characteristics of the Early Mark Spitfires

[robtek]

So let me see if I understand you correctly..

When a spitfire experiences a high speed stall that results in a 'flick roll' it is undesirable..
When a Fw190 experiences a high speed stall that results in a 'flick roll' it is desirable..

Interesting..

Because we have all heard heard the stories of the German Fw190 pilots that used this technique to evade someone on their six, where they would intentionally cause a high speed stall (acc stall) that would cause the Fw190 to 'flick roll' onto its back to preform a fast split-s maneuver.. Which was a good (desirable) trait as far as the German Fw190 pilots were concerned..

So it appears that you have a double standard..

Spit does it it is a bad thing
Fw190 does it it is a good thing

Which IMHO sounds like you are the one who will just mix the resulting explanations as you like

Are you nuts???

Where in this thread have i ever talked about a 190 and its stall behaviour???

Even Spitfire pilots used this accelerated stall flick roll as a last resort escape maneuvre, i've read somewhere.

It is i. e. bad, when one is pursuing in a spit and it happens, changing the hunter to the prey in the worst case.

Btw, the 190 tactic was especially successful in a low level flight :D

[robtek]

I don't understand why folks are going nuts about the Spitfires longitudinal instability, it wasn't a problem for any pilot or how NACA put it "the well know long period oscillations have no correlation with the handling qualities of an airplane". Basically, it doesn't matter .

Maybe you should define those long period oscillations and make sure that is what the OP is talking about.

Looking on the diagrams i see very short period oscillations.

It is still the target to make it as realistic as possible with proved data.

[6S.Manu]

So let me see if I understand you correctly..

When a spitfire experiences a high speed stall that results in a 'flick roll' it is undesirable..
When a Fw190 experiences a high speed stall that results in a 'flick roll' it is desirable..

Interesting..

Because we have all heard heard the stories of the German Fw190 pilots that used this technique to evade someone on their six, where they would intentionally cause a high speed stall (acc stall) that would cause the Fw190 to 'flick roll' onto its back to preform a fast split-s maneuver.. Which was a good (desirable) trait as far as the German Fw190 pilots were concerned..

So it appears that you have a double standard..

Spit does it it is a bad thing
Fw190 does it it is a good thing

Which IMHO sounds like you are the one who will just mix the resulting explanations as you like
Wow! Tagert, this time you've excelled yourself. ;-)

[bongodriver]

Maybe you should define those long period oscillations and make sure that is what the OP is talking about.

Looking on the diagrams i see very short period oscillations.

It is still the target to make it as realistic as possible with proved data.

Short period oscilations are measured in seconds.

Wiki I know but it explains it well enough.....

http://en.wikipedia.org/wiki/Aircraft_dynamic_modes

[Crumpp]

JtD.......long period oscillations

:rolleyes:

Long period Oscillation is not even considered in stability and control. It does not effect any airplane.

Once again, down the rabbit hole we go!!!

[bongodriver]

:rolleyes:

Long period Oscillation is not even considered in stability and control. It does not effect any airplane.

Once again, down the rabbit hole we go!!!


Not really, if an aircraft truly has a problem with short period oscilations then it's practically uncontrollable, and we know thats not true of the Spitfire, at worst the problem is 'slight'

[JtD]

Long period Oscillation is not even considered in stability and control. It does not effect any airplane.Exactly. And it was the only unstable oscillation with the Spitfire.

[robtek]

Exactly. And it was the only unstable oscillation with the Spitfire.

This answer is a try to digress.

We are talking about that it is necessary to move the stick almost completely back to neutral after starting a turn, because of the longitudal slightly negative stability
of the Spitfire (early marks) the turn rate would increase otherwise without further input by the pilot.

We are talking about a very sensitive elevator control, paired with a very short stick travel for large reactions, completed by a relative insensitive aileron control.

We are talking about the former points making it a bit harder to ride the buffet, the excellent stall warning of the Spitfire, without entering the buffet and loosing the turn advantage.

Everything documented and proven.

All this together made the Spitfire to a thoroughbred which needed sensitive hands on the controls.

A plane for the virtuosos, not the ham-fisted.

[bongodriver]

Everything documented and proven.

All this together made the Spitfire to a thoroughbred which needed sensitive hands on the controls.

A plane for the virtuosos, not the ham-fisted.

No, documented and misrepresented.

The Spitfire was famed for being easy to fly 'IN COMBAT' by the very inexperienced pilots of the BoB....

you can embelish it all you want with the 'virtuoso' stuff, that ain't the way it was.

[JtD]

robtek, can you please prepare a list of planes documenting the elevator forces showing the range common to WW2 fighter aircraft and the spots of the various Marks of the Spitfire, depending on the CoG position, on that list? And please also mark the NACA recommendations, on that list.

It would certainly help you getting a perspective. Until you got it, don't waste your time replying to me.

Thereafter, we can talk about what happens say if the pilot does a pullout with a constant stick force in a 109. Will be interesting, too.

Eventually, you may realise that WW2 fighter aircraft in general were nothing for the ham-fisted.

[Sandstone]

All this together made the Spitfire to a thoroughbred which needed sensitive hands on the controls.

A plane for the virtuosos, not the ham-fisted.

And yet it was flown in combat, very successfully, by pilots with very low hours.

[robtek]

@ JTD

i'm not posting for your private tutoring.

@Sandstone

that is not mutually exclusive, i would believe that the more ham-fisted students would find themselves assigned to a Hurricane squadron or even BC.

[Robo.]

i would believe that the more ham-fisted students would find themselves assigned to a Hurricane squadron or even BC.

You would believe wrong.

[robtek]

You would believe wrong.

Sorry, i didn't know that you are that old to be participating on the selection process then.
But please enlighten us all with your first hand knowledge.

[Al Schlageter]

My uncle was training on Seafires when the war ended. Us boys grilled pretty good on the a/c and never once did he mention the elevator was a problem like some are trying to do.

[JtD]

Little jump start for that list, a certainly extreme example:
- F4U with CoG at .334 MAC, trim 1.7° up (neutral at 300 mph, 8500ft): 0in stick travel and 5lbs push force to maintain 5.5g in a steady turn.

Anyway, I got no time for this. Whoever may be interested in getting it right instead of having the last word and discrediting others can certainly dig up more data on his/her own.

[Al Schlageter]

that is not mutually exclusive, i would believe that the more ham-fisted students would find themselves assigned to a Hurricane squadron or even BC.

If they were that ham fisted, they didn't survive the Harvard.

[ACE-OF-ACES]

Are you nuts???
No.. are you?

Where in this thread have i ever talked about a 190 and its stall behaviour???
Please re-read my post and note that I never said you did..

I simply noted how hypocritical some of the blue minded members in this forum can take one airplane trait, in this case the acc stall 'flick' and refer to it as a negative trait when talking about non-blue planes and refer to it as a positive when talking about blue planes..

That is to say I was not specifically talking to you, as much as I was talking about some of the the blue minded members of this forum.

In short, if the shoe fits, ware it, if not than don't.

Even Spitfire pilots used this accelerated stall flick roll as a last resort escape maneuver, i've read somewhere.

It is i. e. bad, when one is pursuing in a spit and it happens, changing the hunter to the prey in the worst case.

Btw, the 190 tactic was especially successful in a low level flight :D
Interesting..

So you agree that both the Spit and Fw190 had this trait..

And you also admitted how it can be a good trait when used to escape..

Yet in your previous post, when talking about the Spitfire you made no mention of the positive..

Only the negatives!

And it was not until I called you out on it that you agreed this trait can be a good thing.

Which speaks volumes about you IMHO..

For future reference

A more balanced approach, that mentions the pros and cons, would have brought a bit more credibility with it.

[Glider]

i would believe that the more ham-fisted students would find themselves assigned to a Hurricane squadron or even BC.

Bomber Command had the first choice of the pilots. Apart from 1940/2 when training would cream off the best to be trained as instructors.

interestingly Germany had a similar problem with Bomber Units having the first choice of pilots and almost a monopoly on staff officers

[robtek]

Little jump start for that list, a certainly extreme example:
- F4U with CoG at .334 MAC, trim 1.7° up (neutral at 300 mph, 8500ft): 0in stick travel and 5lbs push force to maintain 5.5g in a steady turn.

Anyway, I got no time for this. Whoever may be interested in getting it right instead of having the last word and discrediting others can certainly dig up more data on his/her own.

So you are saying that when a F4U at 300mph in level flight at 8500ft is banked it will make a 5.5 g turn without any pilot input except aileron for the banking
and 5 lbs forward pressure on the stick to keep the stick in neutral position?
If so, the plane is trimmed wrong for this turn.

To have a relation to the stick forces the planes should do a similar maneuvre , like a pull up, without airplane specific quirks, as the automatic 5.5g turn surely is one.

In the pull up the Spitfire with normal CoG and cruise speed needs three quarters of a inch stick travel with about 6lbs pull force to have a three g pull up.

I would be interested in the values of other planes in a similar set up.

I'm pretty sure the Spitfire values are pretty unique here.

[robtek]

No.. are you?


Please re-read my post and note that I never said you did..

I simply noted how hypocritical some of the blue minded members in this forum can take one airplane trait, in this case the acc stall 'flick' and refer to it as a negative trait when talking about non-blue planes and refer to it as a positive when talking about blue planes..

That is to say I was not specifically talking to you, as much as I was talking about some of the the blue minded members of this forum.

In short, if the shoe fits, ware it, if not than don't.


Interesting..

So you agree that both the Spit and Fw190 had this trait..

And you also admitted how it can be a good trait when used to escape..

Yet in your previous post, when talking about the Spitfire you made no mention of the positive..

Only the negatives!

And it was not until I called you out on it that you agreed this trait can be a good thing.

Which speaks volumes about you IMHO..

For future reference

A more balanced approach, that mentions the pros and cons, would have brought a bit more credibility with it.

It is always boring when the old red vs blue flag is waved again.

You should remember that it is not about this trait that we are talking, but how to get there!

Willingly or inadvertently?

Of course it was done, as a last resort, even as flick maneuvres were explicitly forbidden in the pilots notes.

Also there are enough Spitfire fans which will point out every positive aspect possible.

Even in a very specific thread where by now at least 50% of the posts are slightly or completely off topic.

Even some of mine, sorry for that.

[bongodriver]

It is always boring when the old red vs blue flag is waved again.

You should remember that it is not about this trait that we are talking, but how to get there!

Willingly or inadvertently?

Of course it was done, as a last resort, even as flick maneuvres were explicitly forbidden in the pilots notes.

Also there are enough Spitfire fans which will point out every positive aspect possible.

Even in a very specific thread where by now at least 50% of the posts are slightly or completely off topic.

Even some of mine, sorry for that.

Flicks were not forbidden in the MkII notes

[ACE-OF-ACES]

It is always boring when the old red vs blue flag is waved again.
Agreed 100%.. Which is why I was so surprised to see you waving the blue flag here in this spitfire thread.. In that your posts are typically balanced.. But here, clearly your bias was playing a part when you only made note of the negative aspects of this trait.

You should remember that it is not about this trait that we are talking, but how to get there!

Willingly or inadvertently?
Agreed 100%.. I noticed that you (and others) were only talking about the 'inadvertently' case.. Which I suspect was done because it was the most negative aspect of the trait.. That is the reason I brought up the 'willingly' case to show how there is a positive aspect to this trait.. And to point out how the blue minded members typically only bring that aspect up when talking about the Fw-190.. Your post is a perfect example of this.. In that you knew in advance there was a positive aspect of this trait.. But you made no mention of it 'here' in this 'spitfire' topic.

Of course it was done,
Glad to see you agree with me

as a last resort,
I don't know if I would go as far as to say last.. I suspect the order in which it was used depended a lot on the pilot and how comfortable he was with it and the situation at hand.

even as flick maneuvers were explicitly forbidden in the pilots notes.
Got Link?

Also there are enough Spitfire fans which will point out every positive aspect possible.
Oh don't get me wrong!

I realize there are blue and red biased members of this forum

Just up until now, I always considered you to be pretty balanced.. but now I see you have your moments of bias too!

Even in a very specific thread where by now at least 50% of the posts are slightly or completely off topic.

Even some of mine, sorry for that.
Enh!

Topics are like a river.. They flow and bend and change direction.. No big whoop! Mater of fact I think one would be hard pressed to show any thread that has not had more than one or changing topics.. Except for the ones that get locked within the first page! ;)

[IvanK]

So what is this thread all about ? The stated purpose by the OP is:

This thread is going to cover the definable and measure stability and control characteristics of the Spitfire. It is not going to cover opinion outside of stability and control engineers.

What this thread is not going to do:

1. Get into a debate about "easy to fly". It is not definable and has no bearing on the measured facts.

2. It is not going to discuss the sustained level turning ability of the aircraft. That is also measurable and definable. For Example, anyone who is capable of doing the math will see that the Spitfire outturns the Bf-109 is steady state constant altitude turns at low velocity.

It has now become the OP's intent to raise this as an issue for the Bugtracker

The issue is that a bugtracker item should be about some genuine bug. That assumes the author actually presents proof that the bug exists. Has he done that ? All I see is too and fro about Real World Spitfire stability. Not much about actual in game behaviour. The OP has stated that he doesn't even have the latest Beta version installed.

http://forum.1cpublishing.eu/showpost.php?p=443004&postcount=12

Now we have yet another huge thread (53 pages as of today !) with opposing views that has supposedly become the ammunition to support a Bugtracker entry that the CLOD Spitfire FM is porked stability wise. 53 pages of discussion but not as far as I can see ANY actual attempt to determine if the existing game FM is actually porked stability wise. The OP opined a while ago that he found the Spitfire hard to trim accurately in pitch .... and which he also said that would make sense considering the stability characteristics of the real aircraft... which (if we accept the stability argument is correct) implies that the current FM stability wise (at the time of his comment) is reasonable.

So how about before raising a Bugtracker defect report the actual defect is demonstrated.

For the record lest we forget The OP has also made comments like :
".......and a dangerous instability exhibited by the Spitfire."
http://forum.1cpublishing.eu/showpost.php?p=419184&postcount=34

[CWMV]

Thank you Ivank for dropping the hammer!
/thread.

[NZtyphoon]

You seem to forget that there is a very distinct difference between slow speed stall behavior, which is desirable, and high speed stall behaviour, which might result in a flick roll and is undesirable.

You just mix the resulting explanations as you like.

Absolute nonsense, both reports combined define the desirable stall behaviour as being both slow speed and high speed - the only one placing a false interpretation on the resulting explanations is your good self and Crumpp

http://i91.photobucket.com/albums/k304/Major_Sharpe/SpitfireVAControlCharacteristics-page-011a.jpg

The Spitfire airplane had the unusual quality that it could be flown in a partly stalled condition in accelerated flight without becoming laterally unstable. Violent buffeting occurred, but the control stick could be pulled relatively far back after the initial stall flow breakdown without causing loss of control.

http://i91.photobucket.com/albums/k304/Major_Sharpe/SpitfireVAStallCharacteristics-page-003a.jpg

http://i91.photobucket.com/albums/k304/Major_Sharpe/SpitfireVAStallCharacteristics-page-004a.jpg

Neither of the NACA reports make the completely unquantified and unsubstantiated claim made by Crumpp that the turn performance was curtailed:

http://i91.photobucket.com/albums/k304/Major_Sharpe/page15j.jpg

[Robo.]

Sorry, i didn't know that you are that old to be participating on the selection process then.
But please enlighten us all with your first hand knowledge.

Oh so if I didn't happen to be participant of the Battle of Britain I have no reason to point out that your opinion is wrong (with all due respect)?

/On the other hand, some other people in this thread would say my precious memories are just anecdotes anyway and they would prefer some piece of paper with a graph drawn on it ;)/

robtek I understand what you're saying, but you are wrong that pilots were selected for Hurris or Spits on the criteria of ham-fistness. ;)

[robtek]

Flicks were not forbidden in the MkII notes

Ok, in the Mk II notes "AIR PUBLICATION 1565 B" is written:

34. Flick manoeuvres.- The high-speed variety of flick-roll
or flick half-roll must ON NO ACCOUNT be done. It is liable to
cause severe strain, is clumsy and uncomfortable, and, being extremely
easy, has no training or other value of any kind. But a flick-roll
at low speed, and low r.p.m. done very gently, is a useful exercise
in timing and control at low speeds, and prevention of spin. It is
done by throttling well back, slowing down to about 140 m.p.h. A.S.I.,
and then very gently easing the stick back and, at the same time,
applying rudder. The nose will rise and yaw, and, as the control
angles are steadily increased, the aeroplane will suddenly start to
"auto-rotate", or flick. If the stick is kept back the aircraft
would then spin, but, as soon as the aeroplane approaches an even
keel (at about the moment when the wings are vertical) the stick is
put forward, and, as the flick ceases, the controls used to steady
the aeroplane until the roll is completed. If this is done too
late the aeroplane will continue to flick, until it does part of
a turn of a spin; if done too soon the flick will stop, and the
rest of the roll must be done by aileron control, in the normal way.

ON NO ACCOUNT CARRY OUT FLICK MANOEUVRES EXCEPT AT LOW SPEEDS,
but remember that low speed makes spinning more likely if the controls
are mishandled. Ample height should be allowed (see Stalling
and Spinning, paras. 17 and 19). other variations of loops, rolls
and so on may be carried out.

The word forbidden is missing and at slow speed they are allowed.

[Crumpp]

Exactly. And it was the only unstable oscillation with the Spitfire.


Did you read the NACA report? Do you need me to highlight the part about long period oscillation is not considered????

Do you understand that none of the Operating Note warnings or NACA measurements include anything about long period oscillation.

The RAE measured stick free oscillation. The NACA measured stick fixed.

In otherwords, the early mark Spitfire was not a hands off aircraft. Left to its own devices, it would eventually destroy itself without pilot input in conditions it was divergent.

[JtD]

You're repeating what I said yet you try to make it sound as if you disagree with me. Why?

[bongodriver]

In otherwords, the early mark Spitfire was not a hands off aircraft. Left to its own devices, it would eventually destroy itself without pilot input in conditions it was divergent.


'NO' mark of spitfire was 'hands off', nor for that matter was 'any' aircraft of the time, have you really raised a thread with all the guff you posted at the beginning just to prove the aircraft would 'eventually' 'if' left 'unchecked' destroy itself? what do you think pilots do? they control the aircraft.

Please tell me this has all been just a bad joke, I ended up banned for doing nothing different to anyone else on this thread.

[FS~Phat]

Gents time to all step away from the keyboard a bit and try and keep it from being personal. I dont want to have to lock the thread but I will if you cant all play nice! ;)

And im not singling anyone out, your all as bad as one another in different ways. :) Which often happens with us passionate lot but please have a bit of humility and humour in your discussions as if you were a couple mates having a good old disagreement over a beer at the pub! If you can discuss with that kind of banter and respect it will be more fun for everyone. REMEMBER NO ONE IS WRONG OR RIGHT im 99% of these discussions, it is discussion of opinion. Facts can be interpreted differently or differing accounts can be made for just about every claim or published article ever made on the spit, the 109 and most of the era's aircraft. Please remember you are not automatically right just because you found something on the "interweb". None of us are experts in testing and we are presenting and interpreting data without the proper training to do so.

So have I made it clear we are all here to learn and discuss and not make things personal, and also try not to take everything personally???
Sometimes its hard I know but please give it go gents. :)

[macro]

My2 pennies.
I diidnt think any fighter was hans off at the time?
If i went to make a cuppa during flight i would most likely come back to a burning wreck no matter the plane i was flying.

We need structural damage modelling for all planes to stop unrealistic manouvers unger high g's. Is there bug tracker for this? Maybe a more sensitve elevator as this is well documented

Not going to comment on the rest as, to be frank, i dont understand it!

[Glider]

In otherwords, the early mark Spitfire was not a hands off aircraft. Left to its own devices, it would eventually destroy itself without pilot input in conditions it was divergent.

Crumpp
Can you name any aircraft, of any type, in any airforce, that was hands free during WW2, ie wouldn't eventually destroy itself without pilot input in conditions it was divergent?

[Osprey]

V1 doodlebug

[41Sqn_Banks]

I don't know about 'hand off' but there were aircraft that couldn't even be flown 'feet off'. Must have been total crap planes ...

[Glider]

V1 doodlebug

Even here there were a fair few failures.

All I am asking Crumpp to do is support/clarify a view.
a) If he believes that it was a common trait amongst WW2 aircraft that aircraft were not hands free then why single out the Spit for critisism.

or

b)If the Spit is an unusual example, then he should be able to nominate one that was hands free.

Pretty simple really.

[Crumpp]

JtD Says:
I don't understand why folks are going nuts about the Spitfires longitudinal instability, it wasn't a problem for any pilot or how NACA put it "the well know long period oscillations have no correlation with the handling qualities of an airplane". Basically, it doesn't matter .


You're repeating what I said yet you try to make it sound as if you disagree with me. Why?

Because I do disagree with you. You confuse apples and oranges between long period oscillations with stick free behaviors and the short period the NACA measured.

The RAE was not stupid. They measured the stick free behavior for a valid reason. You can quickly look at the those graphs to see the Spitfire has positive static and negative dynamic stability stick free. It shows the work load required of the pilot and the ability of the aircraft to maintain equilibrium. The Spitfire was neutral or divergent.

The NACA did not even consider long period oscillation. They only considered short period. Yes, it does matter. It matters so much, it was promptly corrected in the design.

NzTyphoon:

Absolute Nonsense...

Everything is "absolute nonsense" to you, yet you confuse so many things. My advice is to look at the exact conditions and take each statement one at time. It is a scientific report and the language is specific.

You might see that it all fits together and the NACA knew what they were doing. Otherwise, we are forced to concluded that you know more than they do regarding stability and control. I kind of doubt it, though.

Here is a few clues:

1. Guns ports open.....gun ports closed.....(drag picture)

2. Violent pre-stall buffet is not stall motions. It is the the "violent shudder" as noted in the Operating Notes as well as measured data from the NACA

we are presenting and interpreting data without the proper training to do so.

Speak for yourself! :grin:

I worked very hard, investing both time and money for my education. Stability and control was covered and testable.

Can you name any aircraft, of any type, in any airforce, that was hands free during WW2, ie wouldn't eventually destroy itself without pilot input in conditions it was divergent?

Most aircraft are not positive statically stable and negative dynamically stable stick free. It is an unacceptable characteristic.

It is a situation where the the aircraft moves toward the trim condition but increases the force on the axis of motion so that it overshoots the mark. The key is our force is increasing with each oscillation. This causes the motion over time to grow larger and the velocity along the axis of motion to increase. Eventually, the forces will overload the aircraft and it will destroy itself.

[Crumpp]

If the Spit is an unusual example, then he should be able to nominate one that was hands free.

F6F, Hurricane Mk I and Mk II, F4F, Bf-109, FW-190, A6M, and the list goes on...

Glider,

Most aircraft are not positive statically stable and negative dynamically stable stick free. It is an unacceptable characteristic.

[bongodriver]

Most aircraft are not positive statically stable


Really?.....are you sure?

Positive Static Stability—The initial tendency of the airplane to return to the original state of equilibrium after being disturbed.

Static Stability is measured by Short period oscilations.

This sounds like 'most' aircraft to me and is certainly what I have experienced, the Spitfire was neutraly staticaly stable which is what gave it the light controls.

Dynamic stability is shown by measuring the long period oscilation, in the Spitfires case it was 'slightly' longitudinaly unstable and this is is what contributed to the maneuverability of the spitfire.

[macro]

i dont get the "stick free" comments here, why would you fly a plane without holding the stick?

and as someone posted before, can you (anybody) explain for my better understanding how what being discussed here is different than in game :confused: i.e what it should be doing compared to what it is doing now

[fruitbat]

A question for you all, can't find the answer myself, what was the first aircraft fitted with bob weights, and particuarly the first british plane?

Was it the Mk V Spit?

Thanks in advance.

[bongodriver]

A question for you all, can't find the answer myself, what was the first aircraft fitted with bob weights, and particuarly the first british plane?

Was it the Mk V Spit?

Thanks in advance.

You could also search for 'inertia weight'

[CaptainDoggles]

Really?.....are you sure?You took that out of context. He's saying most aircraft do not have positive static but negative dynamic stability when stick free.

[JtD]

Because I do disagree with you.In that case you're disagreeing with NACA. Take it up with them.

[robtek]

No, JtD,
YOU are disagreeing with NACA, because YOU wrote that the long period oscillation is the only unstable oscillation for the Spitfire, where the NACA report ignored the long period oscillations as insignificant.

[JtD]

Maybe it helps if I sum it up:

A.&A.E.E. tested Spitfire K9788 (a Spitfire I) and it showed increasing long period oscillations, which means it is dynamically unstable.

NACA did not bother to investigate these, as "the well know long period oscillations have no correlation with the handling qualities of an airplane". NACA tested a Spitfire V. It evaluated short period oscillations, which all were damped satisfactory, and evaluated static stability, which was found to be neutral to positive flaps up, and negative flaps down.

Now I absolutely agree with NACA, in particular with the statement that the long period oscillations are irrelevant in terms of handling and in fact, dynamic instability was not atypical for fighter aircraft of the time. The Hurricane for instance, having gone through similar trials, proved to be far more dynamically unstable.

I've neglected the flaps down instability, which I consider irrelevant in air combat, because flaps down was no condition for combat.

As for the other qualities evaluated by NACA, be it good or bad, it sums up that there's nothing critical. Only characteristic, in that some points are rather weak, some excellent.

And all the hype about dangerously low elevator forces and changes to pilot notes - it was decided to add the part of the Mk II notes, which is repeatedly quoted here, after a total of 3 (three) Spitfire I's were lost due to mid air wing failures and investigation found that inexperienced pilots coming in fresh from training mostly in bi-planes needed an extra warning because they simple were not familiar with high speed pull outs and trimming in high speed dives.

The weakest point in terms of control were the fabric covered ailerons, whereas the overall control characteristics made the Spitfire an easy plane to fly, and an easy plane to fly to the limits. For a WW2 fighter aircraft.

[NZtyphoon]

The RAE was not stupid. They measured the stick free behavior for a valid reason. You can quickly look at the those graphs to see the Spitfire has positive static and negative dynamic stability stick free. It shows the work load required of the pilot and the ability of the aircraft to maintain equilibrium. The Spitfire was neutral or divergent.
Yet the RAE were stupid enough not to have any standards, according to Crumpp.

Everything is "absolute nonsense" to you, yet you confuse so many things. My advice is to look at the exact conditions and take each statement one at time. It is a scientific report and the language is specific.

I would recommend you do the same Crumpp, instead of layering your interpretations on straight-forward comments.

[Robo.]

Maybe it helps if I sum it up:

A.&A.E.E. tested Spitfire K9788 (a Spitfire I) and it showed increasing long period oscillations, which means it is dynamically unstable.

NACA did not bother to investigate these, as "the well know long period oscillations have no correlation with the handling qualities of an airplane". NACA tested a Spitfire V. It evaluated short period oscillations, which all were damped satisfactory, and evaluated static stability, which was found to be neutral to positive flaps up, and negative flaps down.

Now I absolutely agree with NACA, in particular with the statement that the long period oscillations are irrelevant in terms of handling and in fact, dynamic instability was not atypical for fighter aircraft of the time. The Hurricane for instance, having gone through similar trials, proved to be far more dynamically unstable.

I've neglected the flaps down instability, which I consider irrelevant in air combat, because flaps down was no condition for combat.

As for the other qualities evaluated by NACA, be it good or bad, it sums up that there's nothing critical. Only characteristic, in that some points are rather weak, some excellent.

And all the hype about dangerously low elevator forces and changes to pilot notes - it was decided to add the part of the Mk II notes, which is repeatedly quoted here, after a total of 3 (three) Spitfire I's were lost due to mid air wing failures and investigation found that inexperienced pilots coming in fresh from training mostly in bi-planes needed an extra warning because they simple were not familiar with high speed pull outs and trimming in high speed dives.

The weakest point in terms of control were the fabric covered ailerons, whereas the overall control characteristics made the Spitfire an easy plane to fly, and an easy plane to fly to the limits. For a WW2 fighter aircraft.

Thank you JtD ;) This is pretty much how I read the facts in this thread.

[robtek]

The instability in the NACA report is, that a constant stick input, say one inch back with 6lbs pressure, led to a ever increasing g-load, and that was the malus for the Spitfire controls.

The ideal reaction would have been i. e. pull the stick 3 inches back with 15 lbs pressure and get a constant 5 g pull up.

[JtD]

The instability in the NACA report is, that a constant stick input, say one inch back with 6lbs pressure, led to a ever increasing g-load, and that was the malus for the Spitfire controls.No, there's nothing like that in the NACA reports. Neither in pull ups (figure 12), nor in turns (figure 21). The curves clearly show progressive elevator angle (stick travel) and progressive forces, even though the stick travel is small.

[Crumpp]

No, there's nothing like that in the NACA reports.

Yes it is what the NACA report says.

ONLY the abrupt pull ups are stick free.

The instability in the NACA report is, that a constant stick input, say one inch back with 6lbs pressure, led to a ever increasing g-load, and that was the malus for the Spitfire controls.


Correct. The abrupt turns and all other conditions are stick fixed. The NACA did have to modify their force gauge to allow the pilot to adjust the force holding the stick fixed so as not to exceed the airframe limitations. He could move it to keep from damaging the airframe.

That is all explained in the report.

[Crumpp]

As for the other qualities evaluated by NACA, be it good or bad, it sums up that there's nothing critical.

:rolleyes:

JtD, they flat out state the stick fixed longitudinal stability is unacceptable. That is the NACA, not me.

Why do you think bob-weights were added to the design to fix the longitudinal stability?

Because they just felt like changing something? Maybe they were bored and had nothing else to do?

Or maybe, just maybe, there was a real engineering issue with the longitudinal stability that required a real engineering solution? Nahhhh!!!

;)

http://img99.imageshack.us/img99/5619/spitfirestability.jpg (http://imageshack.us/photo/my-images/99/spitfirestability.jpg/)

[JtD]

NACA shows progressive stick travel and elevator force over lift coefficient and normal load. You are directly contradicting NACA. I'd appreciate if you could point out the chart or table you are basing your conclusion on.

Additionally - the Spitfire stability "failed to meet an accepted requirement". This does not make the stability unacceptable. It may seem to be the same for people unfamiliar with testing and test reports, but it is not. In this case the difference is evident from the fact that the Spitfire was accepted into service with 30+ air forces worldwide, among them the USAAF. This would not have happened had the stability been unacceptable.

[ACE-OF-ACES]

Additionally - the Spitfire stability "failed to meet an accepted requirement". This does not make the stability unacceptable. It may seem to be the same for people unfamiliar with testing and test reports, but it is not. In this case the difference is evident from the fact that the Spitfire was accepted into service with 30+ air forces worldwide, among them the USAAF. This would not have happened had the stability been unacceptable.
Agreed 100%

[bongodriver]

NACA shows progressive stick travel and elevator force over lift coefficient and normal load. You are directly contradicting NACA. I'd appreciate if you could point out the chart or table you are basing your conclusion on.

Additionally - the Spitfire stability "failed to meet an accepted requirement". This does not make the stability unacceptable. It may seem to be the same for people unfamiliar with testing and test reports, but it is not. In this case the difference is evident from the fact that the Spitfire was accepted into service with 30+ air forces worldwide, among them the USAAF. This would not have happened had the stability been unacceptable.


+1

it's like adopting a standard where everything has to be purple and then testing something which is green and surprise surprise it fails the purple standard.

This was a test on a MkV, nothing in the test mentions a similarity with earlier models, and the MkV had a different weight and balance.
Was it the Americans that advised the addition of the bob weight?
I believe some RAF units asked for it to be removed so they could have the original flying qualities back, doesn't sound like the original ones were so bad in that case.

This whole thread has been about making a mountain out of a molehill.

[Glider]

In my reply to my question about any examples of any aircraft of any type in any airforce that was stable enought to meet your requirements and your reply



Most aircraft are not positive statically stable and negative dynamically stable stick free. It is an unacceptable characteristic.

It is a situation where the the aircraft moves toward the trim condition but increases the force on the axis of motion so that it overshoots the mark. The key is our force is increasing with each oscillation. This causes the motion over time to grow larger and the velocity along the axis of motion to increase. Eventually, the forces will overload the aircraft and it will destroy itself.

I take it that your reply is a very long way of saying no, you have no examples.

The words you have written are as far as I can ideological rubbish and would depend on the pilot being stupid enough to overcompensate with every oscillation. Nothing to do with examples which I take it you cannot supply.

[NZtyphoon]

Why do you think bob-weights were added to the design to fix the longitudinal stability?

Because they just felt like changing something? Maybe they were bored and had nothing else to do?

Or maybe, just maybe, there was a real engineering issue with the longitudinal stability that required a real engineering solution?


Quill devotes an entire chapter to longitudinal stability (pages 229-241 Murray 1983) in his book "Spitfire a Test Pilot's Story" in which he goes into detail about the problems involving several Spitfire Vs which broke up in 1942; Quill describes the problem of Spitfire Vs breaking up; he then goes on to describe the solutions which were a): to ensure that when new equipment was added that the loading was kept within limits and b):the design of bobweights, which were added to the elevator circuit, as well as the modified elevators fitted to later Spitfire marks. After the bob-weights were fitted, and the loading sorted out, the problem disappeared.


Quill
"In general configuration the Mk I and Mk II production aeroplanes were almost identical to the prototype and so there was no problem with their stability." (231-232)

"The Mk III Spitfire did not go into production, but the success of the bobweight experiment in curing its instability...opened up the possibility of its use for later marks of Spitfire....which was just as well as we had to...respond to a nasty situation which developed in 1942.
The Mk V aircraft was...in full service with Fighter Command and,...a fair amount of additional operational equipment had gradually crept into the aircraft, most of it stowed within the fuselage. The aftmost acceptable position for the aircraft's centre of gravity had been fixed in the mormal course of flight testing by the firm and by the A & AEE....Any rearward movement of the centre of gravity in service, for whatever reason, would begin to destabilise the aircraft. Therefore, for each sub-variant of the Mk V detailed instructions for the correct loading of the aircraft were issued to squadrons....However the importance of these loading instructions was not generally appreciated in squadrons and in the daily round of operational activity they tended to be disregarded." (pages 232-233 -Quill goes on to describe 65 Sqn's Spitfire Vbs which were found to be dangerously unstable)

"There was thus a real chance that, as of that moment, in almost every squadron in the Command Spitfires were flying in a dangerous state of instability....Up to that time there had been a distressing and increasing incidence of total structural failure of Spitfires in the air, which was causing great comcern in the MAP and especially at Supermarine." (pages234-235) Once the bobweights had been introduced and, in later marks, the modified mass balances on the elevators...it was statistically established that, as soon as the longitudinal stability of the Spitfire was thus brought under control, the problem of the unexplained breakings-up of aircraft in mid-air,...'softly and suddenly vanished away'." (page 238 )

http://i91.photobucket.com/albums/k304/Major_Sharpe/spits2.jpg

So the bob-or inertia weights were introduced in 1942 to help solve bad loading or overloading of Spitfire Vs at Squadron level - it had nothing to do with NACA's report.

[Crumpp]

NACA shows progressive stick travel and elevator force over lift coefficient and normal load.

I have to figure the slope anyway for the bugtracker. Might as well do it now.

Yellow:

Acceleration over time 3.5G-(-.5G) divided by 4.5s-3.5s = m
m = 4

Stick force over time: (19lbs - 0lbs) divided 5lbs/G all divide by 4.5s-3.5s = m
m = 3.8

The slopes should match and they are close enough. However, our stick force grows at a slower rate than our acceleration. This is the initial input of the pilot.
Now let's see the instability.

Green:
Stick force over time 15lbs-15lbs divided by 5lbs/G all divided by 6.8s-5.5s = m
m = 0
Of course m = 0, our stick is held fixed by the force measurement equipment
Acceleration over time 4.2G-3.2G divided by 6.8s-5.5s = m
m = .76

So, while our stick remains fixed, the aircraft continues to accelerate on its own. As the nature of instability, there is no correlation stick force input and acceleration.

Now, our pilot in this case only input force to reach 3.5G. In a stable airplane, we should see the aircraft dampen all subsequent accelerations which means the aircraft would not exceed 3.5G without control input.
In this case, the instability or divergent oscillation a 4.2G acceleration with stick fixed slightly below the stick force required to produce a 3.5G acceleration.

[Crumpp]

So the bob-or inertia weights were introduced in 1942 to help solve bad loading or overloading of Spitfire Vs at Squadron level - it had nothing to do with NACA's report.


:confused:

Are we really gonna have this conversation??

[NZtyphoon]

:confused:

Are we really gonna have this conversation??

:rolleyes:

JtD, they flat out state the stick fixed longitudinal stability is unacceptable. That is the NACA, not me.

Why do you think bob-weights were added to the design to fix the longitudinal stability?
:rolleyes:
I can't help it if you're confused: the-reason-inertia-weights-were-introduced-was-because-Spitfire Vs-were-being-badly-loaded-at-an-operational-level-in-1942. As more operational equipment was introduced some squadrons were ignoring the loading diagrams. It had nothing to do with the NACA report. :roll:

[Crumpp]

it was statistically established that, as soon as the longitudinal stability of the Spitfire was thus brought under control

Why don't you read the Operating notes for any early mark Spitfire.

"longitudinal instability" is used often....

I am sure the Spitfire Mark V increase in weight and speed caused an unmistakeable as well as difficult to ignore increase in in-flight break ups.

[NZtyphoon]

:rolleyes:I am sure the Spitfire Mark V increase in weight and speed caused an unmistakeable as well as difficult to ignore increase in in-flight break ups.

Nope, you are quoting well out of context: what caused some break-ups was poor loading by the squadrons, as was explained by Jeffrey Quill:

Quill
"In general configuration the Mk I and Mk II production aeroplanes were almost identical to the prototype and so there was no problem with their stability." (231-232)

"Therefore, for each sub-variant of the Mk V detailed instructions for the correct loading of the aircraft were issued to squadrons....However the importance of these loading instructions was not generally appreciated in squadrons and in the daily round of operational activity they tended to be disregarded." Once the bobweights had been introduced and, in later marks, the modified mass balances on the elevators...it was statistically established that, as soon as the longitudinal stability of the Spitfire was thus brought under control, the problem of the unexplained breakings-up of aircraft in mid-air,...'softly and suddenly vanished away'." (page 238 )

http://i91.photobucket.com/albums/k304/Major_Sharpe/spits2.jpg

[JtD]

Now let's see the instability.

Green:You can find similar spots in turn time histories for nearly all WW2 aircraft tested this way. Or, you can pick another spot on the very same curve and will find different figures or pick the curves 16-18 and get different results again. If it was a plane quality, there'd be the same behaviour in every test they've done, but it isn't.

NACA evaluates the the behaviour:

"In turns at speeds high enough to prevent reaching maximum lift coefficient because of the excessive accelerations involved, the small static longitudinal stability of the Spitfire caused undue sensitivity of the normal acceleration to small movements of the stick. As shown by the time histories of high-speed turns (figs. 15 to 18), it was necessary for the pilot to pull back the stick and then ease it forward almost to its original position in order to enter a turn rapidly without overshooting the desired normal acceleration. Although this procedure appears to come naturally to a skillful pilot, flight records from other airplanes show that a turn may be entered rapidly and the desired normal acceleration may be held constant by a single rearward motion of the stick provided the static stability of an airplane is sufficiently large. By careful flying, the pilot was able to make smooth turns at high speed, as shown by figures 17 and 18. Ordinarily, however, small movements of the stick caused appreciable variations in the normal acceleration, as shown in figures 15 and 20."

So, what they are saying again is that there are large reactions to small stick travel. Not that the plane was unstable. The stick force gradient and the elevator angle gradient were both found to be positive, as I've said already.

[Crumpp]

So, what they are saying again is that there are large reactions to small stick travel. Not that the plane was unstable.

Yes, they definately say there are large aceleration changes for a small amount of elevator travel.

The other part is that they do say the airplane is unstable. Neutral or unstable......

At a neutral or unstable condition, the Spitfire is not able to hold a constant aceleration in a turn.

One can run the math on Cm and see that too.

flight records from other airplanes show that a turn may be entered rapidly and the desired normal acceleration may be held constant by a single rearward motion of the stick provided the static stability of an airplane is sufficiently large.

At forward CG, the static stability is sufficiently large. At normal and aft CG the static margin is neutral or unstable.

[bongodriver]

At forward CG, the static stability is sufficiently large. At normal and aft CG the static margin is neutral or unstable.

But this applies to 'all' aircraft, it seems pretty odd to criticise the Spitfire for something that is universal, this is exactly the same problem the Mustang has with a full fuselage tank.

to determine how much of a problem this is for the Spitfire a decent weight and balance schedule is needed, from that it can be calculated how much fuel burn is required to put the CoG forward.

[Sandstone]

At a neutral or unstable condition, the Spitfire is not able to hold a constant aceleration in a turn.

But is perfectly capable of doing so when flown by a pilot of even limited experience.

[Sternjaeger II]

I always thought that the "breaking up in the air" of early Spits was mainly caused by design flaws on the tail section (like in the early Typhoons) which emerged in high speed dives.

[Crumpp]

But this applies to 'all' aircraft

No it does not.

It depends on the static margin. The static margin will move as the CG changes but most aircraft are designed to have positive stick fixed stability at the most rearward position.

In fact, that point defines the rear CG limit.

[IvanK]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

[Crumpp]

you are quoting well out of context

No I am not. You don't seem to understand the effect of weight and speed on airframe loads.

I have the entire report and will post it as part of the bugtracker.

Once again, you are going down the rabbit hole.

[macro]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

Thats what i want to know.

[winny]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

And this, gentlemen, is the 64,000 dollar question...

[JtD]

The other part is that they do say the airplane is unstable.NACA says: "... the small static longitudinal stability of the Spitfire...". Not unstable...it's there in black and white, first sentence of the relevant paragraph. And, again, the stick force gradient and the elevator angle gradient were both found to be positive.

[fruitbat]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

Yes, I'm curious to.

And how has it been tested?

[Sandstone]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

Indeed.

Crumpp, you should answer this one.

[NZtyphoon]

No I am not. You don't seem to understand the effect of weight and speed on airframe loads.

I have the entire report and will post it as part of the bugtracker.

Once again, you are going down the rabbit hole.

The only one going down a rabbit hole is Crumpp, who doesn't seem to understand the cause and effect of bad cg loading on a basically sound design and now assumes that the Spitfire V was prone to break up because it had taken on extra weight and could fly faster.

And what report is Crumpp going to post?

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

Second question, how exactly can Crumpp's bugtracker replicate the longitudinal stability characteristics Crumpp thinks the CLOD Spitfire I & II should have, when there is no option for rough air conditions?

[Crumpp]

NACA says: "... the small static longitudinal stability of the Spitfire...". Not unstable...

:rolleyes:

[JtD]

You keep quoting the summary as if it was the only and complete assessment, but it is not. The paragraph dealing with stability as such already gives a more detailed description, that being in general agreement with the summary, but more specific in that "The stability was essentially neutral in all flap-up, power-on conditions of flight except at low speeds, where some rearward motion of the stick occurred." And if we look for further detail on behaviour in accelerated flight, we find "the small static longitudinal stability of the Spitfire" I quoted. And this is proven by stick travel and stick force gradients, for anyone to see.

This doesn't change the fact that NACA found the plane neutral with power off and unstable with flaps down, but this is of no interested in power on accelerated flight.

If you want to sell instability to me, or anyone else who's got a good understanding of the matter, you'll need to explain how both of the above gradients can be positive in an unstable aircraft and how it was possible to fly the smooth stick fixed turns as shown in figures 17 and 18. Repeating the summary yet another time will not do the trick.

I think there's no point in submitting anything to the bugtracker before this has been clarified.

[Glider]

I think its worth remembering that Handling isn't a precise science. Many aircraft have been designed by trained designers well schooled in the theory and science. Yet all at one point or another have produced aircraft that handled poorly.
Any theory needs to be supported by comments from test pilots and others to support that view.

This is something that has often been requested but has yet to be shown apart from one attempt (posting 321 page 33) which backfired.

[TomcatViP]

Ehhh, guys you should calm up.

There was a lot of planes designed in the mid 30's that had pitch instability.

I won't submit you to an aerodynamics exam but Britain, it's a fact, was lagging behind the leading countries in that field of knowledge that were Germany and USA. USA was among the leading country in part because Karman went to work at the NACA in 35/36 (read his book - it's a fascinating tale of time of the great pioneer).

Anyway this is why many british design were too rounded or to thin or somewhat bulky. Not individualy (there was many talented scientist and aerodynamist) but as an institution, they did not master the viscous conditions as much as the leading nations. What was the key to understand plainly aerodynamics.

France had the same amount of knowledge as UK at the time. This is why most of the French design were seen as low performers as the testing didn't meet the expectations of the design teams (hence lower strain on HP demands, higher thickness ratio, lower wing surfaces etc... - One good example of that is the Curtiss H-75 (P-36) from US that was designed before 1935).

Russian did realize that and after the outbreak of WWII a high priority was given again to fundamental research and testing (the TSAGI) up to the point that the late Russian design during the war were above performer (at least in their prototype form). By the way, a little note to the guy in this forum that put Britain at the forefront of aeronautics knowledge when a bit of search will tell you that all this started with Joukowsky, a Russian Mathematician (http://en.wikipedia.org/wiki/Joukowsky_transform)

Before you start repeating your tirade about how British were at the for front of the sciences of aerodynamics etc... Let me tell you this: The father of the Buccaner, leading engineer for years at Blackburnand then BAe (started his carreer at Gloster if I do remind well) explains all this in his book. It tell us the fascinating story of how the Brits test facility were relaying on inappropriate methods (at least not accurate) to simulate airflows in the 40's.

Oh, and by the way, he was also on the board of the British team that worked teh design of the SuperUberModern EF2000billions£. That tell you a lot about how much this design is ready to plink the 21'st century threats - Bah it's another story!

I don't have the name of course. But in regard to your disgusting way of smoking every thread, irrespective prose, and what can be called blatant lying I won't do a single search.

Easy to found : Buccaneer story published in the 80's - small format - no images just text- Cover red, white and blue of course !

[Glider]

I would like to know the name of the book if possible, the Bucaneer was one of the planes I was trained on and had a huge respect for it. Well ahead of its time and in many ways better than the Tornado that 'replaced' it, in my totally unbiased opinion.

As for the theory that the USA were so far ahead there are a few problems with that.

In 1938 the period when the Hurricane, Me109 and SPitfire were entering service the USA had the P35 and P36. Most wouuld consider the P36 to be the better machine but the P35 won the Contest for the USAAF.
The P43 entered service in 1940 when the RAF were getting the Spit II and the German Airforce were close to the 109F. The P40 was always behind the curve.

In bombers its a similar story. The Luftwaffe and RAF had Wellington, He111, Ju88, Do 17 Stuka, Hampden, even the Whitley. The USA had the B18, the Boston was on the way but not until 1940 which was too late and this had some issues. It wasn't all great, the Battle is an obvious example but the european countries had options.

I find it hard to see where this significant advantage the USA had in theory was being applied.

In transport aircaft the USA had a clear lead and naval aircraft.

The USA may have had theoretical advantages but its wrong to overstate it. Its also worth remembering that production of aircraft such as the Fw190 and Mosquito were close behind

[TomcatViP]

I would like to know the name of the book if possible, the Bucaneer was one of the planes I was trained on and had a huge respect for it. Well ahead of its time and in many ways better than the Tornado that 'replaced' it, in my totally unbiased opinion.

Will do my best Glider but can't promise anything.

Edit : Here it is ! Sisi it include the Bucc full story ;) The book tittle was just made sexier with the added types for the neophytes ;)

Buy
http://www.amazon.co.uk/exec/obidos/ASIN/1853100935/thunderandlightn

Review
http://www.flyingbooks.co.uk/acatalog/From_Spitfire_to_Eurofighter.html

[NZtyphoon]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.06.17582+Hot Fix

According to Crumpp the Spitfire was dangerous:

http://forum.1cpublishing.eu/showpost.php?p=424903&postcount=245

"The solution for the unacceptable and dangerous longitudinal instability of the Spitfire was bob-weights." These were added not because the NACA made a mistake in some half baked theory on weight and balance calculations. They were added by the RAE to correct a serious stability and control issue with the design."

(No they weren't, they were added by Supermarine to control a truly dangerous instability problem caused by poor loading at squadron level, but we can let Crumpp away with his poor grasp of history - he's only an engineer. :rolleyes:)

One solution to the "dangerous" instability exhibited by the Spitfire would be for the IL2 developers to add bob-weights - ASAP!

[Holtzauge]

While no one can argue that the NACA was not at the forefront of aeronautics in the mid 1930's, the bashing of British aeronautics and the raising US dito as a beacon of enlightenment seems a bit simplistic given that the US fielded a TRANSPORT aircraft at this time that was actually longitudionaly UNSTABLE in some flight conditions: The Douglas DC-3 was with normal rated power and also under approach conditions statically UNSTABLE. See NACA TN 3088 (Can be downloaded from the NASA NTRS server) page 31 figure 5. Now compare that to figure 9 page 27 of NACA L-334: The Spitfire FIGHTER shows a NEUTRAL/SLIGHT POSITIVE stability and a better elevator force/speed curve than the UNSTABLE DC-3 TRANSPORT.

While both aircraft undoubtedly would have benefited by a larger margin of stability from a control perspective (logically larger for the DC-3 and smaller for the Spitfire) it is by far easier to overlook NEUTRAL stability in a FIGHTER rather than actual INSTABILITY in a TRANSPORT. Also note that the INSTABILITY inherent in the DC-3 did not stop it from becoming a legendary an popular aircraft held in high esteem by the pilots who actually FLEW them so I think one should be careful before making assertions that the NEUTRAL/SLIGHT POSITIVE stability exhibited by the Spitfire was a serious problem. Another thing to consider is that neutral stability in general means less drag and therefore higher performance and that the pilot can generally more easily transition between high and low speed conditions without retrimming or excessive control forces, both of which are valuable traits in a FIGHTER design.

Finally, I can only second the call to present what is actually wrong with the current Spitfire modeling in CoD: As the saying goes, if it ain't broke then don't fix it. While I readily admit to not having read through the entire 59 pages with a loupe the formulation of the actual problem and what needs to be fixed escapes me.

[Glider]

Will do my best Glider but can't promise anything.

Edit : Here it is ! Sisi it include the Bucc full story ;) The book tittle was just made sexier with the added types for the neophytes ;)

Buy
http://www.amazon.co.uk/exec/obidos/ASIN/1853100935/thunderandlightn

Review
http://www.flyingbooks.co.uk/acatalog/From_Spitfire_to_Eurofighter.html

Thanks for that

[Crumpp]

If you want to sell instability to me, or anyone else who's got a good understanding of the matter, you'll need to explain how both of the above gradients can be positive in an unstable aircraft and how it was possible to fly the smooth stick fixed turns as shown in figures 17 and 18.

:rolleyes:

http://img827.imageshack.us/img827/8361/figures17and18.jpg (http://imageshack.us/photo/my-images/827/figures17and18.jpg/)

or anyone else who's got a good understanding of the matter,

Your good understanding? Is that with the long period oscillation's your claimed, the slopes of the curves, the difference between stick fixed, stick free, dynamic and static?? I am confused as to where your good understanding is demonstrated.

[Holtzauge]

OK, I see the problem now: What Crumpp fails to understand is that while the actual stick movement is small, figures 17 and 18 show that the pilot uses between 10-20 lb of pull to HOLD the turn. If one looks at the force histogram its apparent that a relatively constant pull force is needed to keep the plane in the turn. So no increased pull force no increased load factor. Wherein lies the big problem? What would be troublesome would be if there was a need to apply a push force or substantial unloading in order not to tighten up the turn once it had been initiated. However, the histogram shows no such tendencies i.e. the behaviour looks quite benevolent.

Maybe this is also why we on the one hand have numerous accounts from pilots who actually flew the Spitfire and appreciated it and on the other have a private pilot armchair expert who is of a different opinion based on a myopic and selective interpretation of data.

[Crumpp]

OK, I see the problem now: What Crumpp fails to understand is that while the actual stick movement is small, figures 17 and 18 show that the pilot uses between 10-20 lb of pull to HOLD the turn. If one looks at the force histogram its apparent that that a relatively constant pull force is needed to keep the plane in the turn. So no pull force no increased load factor. Wherein lies the big problem? What would be troublesome would be if there was a need to apply a push force in order not to tigthen up the turn once it had been initiated. However, the histogram shows no such tendencies i.e. the behaviour looks quite benevolent.

Maybe this is also why we on the one hand have numerous accounts from pilots who actually flew the Spitfire and appreciated it and on the other have a private pilot armchair expert who is of a different opinion based on a myopic and selective interpretation of data.


However, the histogram shows no such tendencies i.e. the behaviour looks quite benevolent.


:rolleyes:

Spitfire Mk I Operating Notes, July 1940:

http://img109.imageshack.us/img109/7976/page10jv.jpg (http://imageshack.us/photo/my-images/109/page10jv.jpg/)

http://img26.imageshack.us/img26/2599/page12dh.jpg (http://imageshack.us/photo/my-images/26/page12dh.jpg/)

http://img542.imageshack.us/img542/9202/page13o.jpg (http://imageshack.us/photo/my-images/542/page13o.jpg/)

http://img607.imageshack.us/img607/2471/page15j.jpg (http://imageshack.us/photo/my-images/607/page15j.jpg/)

http://img651.imageshack.us/img651/2456/page16lu.jpg (http://imageshack.us/photo/my-images/651/page16lu.jpg/)

By all means continue Holtzauge.

Let's stick to what is definable and measureable, as this is my thread.

[Holtzauge]

Let's stick to what is definable and measureable, as this is my thread.

Yes, let's stick to that: To begin with follow your own advice: What you posted above is as has now been pointed out numerous times some general advice to the pilot on handling characteristics and hardly qualifies to your own strict limitations to what is definable and measurable so you can remove them from "your" thread.

Now what is pertinent and admissible according to your own definition above are figures 17 and 18 so please enlighten us with how these support your case as opposed to mine and JtD's interpretation above.

[Crumpp]

figures 17 and 18

Why don't read the report about figures 17 and 18?

Here, I will post it once again....

http://img198.imageshack.us/img198/8361/figures17and18.jpg (http://imageshack.us/photo/my-images/198/figures17and18.jpg/)

Now, Holtzuage....

I would love to have this conversation with you. Should be a wonderful and refreshing change given your claims to be an engineer.

I wait with baited breath for your measured and definable evidence showing the early Mark Spitfire to have acceptable longitudinal stability by any modern definition. Feel free to use the RAE post war standards, NACA, R-1815A, SF119A, MIL-F-8785, FAR, JAR....

You pick!!

Looking forward to it. :grin:

[Glider]

Personally I am waiting for you to supply examples of any WW2 fighter that met modern standards

We know that the Spit didn't but we also know it wasn't a problem. We also know that the DC3 didn't meet the standards and can only assume that the people still flying these aircraft 70+ years after they were designed don't realise that they are so unstable.

We are still waiting for a load of information that you said you had that supported your case.

PS don't claim to have the training or qualifications that you claim to have but IIRC, MIL-F-8785 was mainly short period damping regarding roll, not the longitudinal stability of an aircraft

[Crumpp]

Personally I am waiting for you to supply examples of any WW2 fighter that met modern standards


I have already answered your question. It is in the thread and it is specific to you about this same question.

I am not going to continue to post the information so that you can ignore it when convenient.

[Glider]

I have already answered your question. It is in the thread and it is specific to you about this same question.

I am not going to continue to post the information so that you can ignore it when convenient.

That must be when the negative comment was on the Prototype Spit and the second paper on the first production spit, confirmed that the problem was fixed.

Be fair, I did ask at the time if that was all you had and you didn't add anything to it.

So to sum up you have no examples (apart from the above) from any pilot or any test establishment of any nation to support the view that the Spitfire was difficult or uncomfortable or dangerous to fly.
Thank you for that

[Crumpp]

The DC-3 was unstable in cruise flight only at it's most rearward CG limit. That limit was moved forward.

[Glider]

The DC-3 was unstable in cruise flight only at it's most rearward CG limit. That limit was moved forward.

You can of course prove that statement ?

[Crumpp]

I would post the NACA report but it is too big even zipped.

Yes, only at the rearward CG limit was the aircraft unstable and only below 120IAS. Above 160IAS, and trimmed out at the rearward CG limit, it was "almost neutral".

[Crumpp]

So to sum up you have no examples

No, I gave you a list of examples. You did not bother to read them.

[Glider]

Actually I did and I have checked what you have said. Unfortunately what you have said and what so far I have checked don't tally. For example the Me109 certainly doesn't fit your criteria, without a rudder trim then eventually the aircraft will need manual input. It is also stated in the Zero report that constant attention is needed on the rudder. The Fw190 has almost no trimming tabs on the controls and in my limited experience of powered aircraft without trimming tabs you cannot be hands off and always have to stay in control

It is a similar story when you gave me a list of books that said that the Me109 could turn with the Spitfire, I have checked two of them out and they don't seem to say what you said they say. I did ask where they did agree with your statement, but there was no reply.

I have asked for a list of the flight tests or reports from test establishents/test pilots that say that the SPit was difficult or dangerous or uncomfortable to fly. You stated that you had these but as we have discovered it only referred to the prototype and that was fixed in first production.

You have a habit of being very very selective over what you state and often don't read the papers in their entirity before forming a picture, I can give a number of examples if you so wish.

Take the regs you just quoted. I am pretty sure that MIL-F-8785 is to do with the rolling of an aircraft so what has this to do with longatudinal stability?
I could be wrong on this so if you could confirm this I would appreciate it. However it again from memory it calculated the characteristics of five different types of aircraft from transports to fighters defining what was acceptable for each.
However I cannot help suspect that you are trying to impress and blind us with a list of regs rather than concentrate on what is correct.

[Al Schlageter]

Like the 100 octane threads, Crumpp has struck out again.

[IvanK]

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.07.18301+Hot Fix ?

[NZtyphoon]

I would post the NACA report but it is too big even zipped.

Yeah, right, it's HUGE - all 68 pages and 16 mb! :rolleyes:

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930083829_1993083829.pdf

Now Mr Crumpp

*Exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.07.18301+Hot Fix ?

*How exactly can Crumpp's bugtracker replicate the longitudinal stability characteristics Crumpp thinks the CLOD Spitfire I & II should have, when there is no option for rough air conditions?

[Crumpp]

16 mb

And you are limited to 14.31 zipped.

So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.07.18301+Hot Fix ?

It will be in the bug tracker. Why don't you do some testing?

[NZtyphoon]

It will be in the bug tracker. Why don't you do some testing?

Because you are the one pushing this, how about you explain in this thread exactly what needs to be fixed, and how you propose to fix the perceived problem?

How exactly will Crumpp's bugtracker replicate the longitudinal stability characteristics Crumpp thinks the CLOD Spitfire I & II should have, when there is no option for rough air conditions - one of the main warnings posted in the Pilot's Notes described flying in bumpy conditions.

How will Crumpp's proposed changes affect other flight characteristics of the CLOD Spitfire I & II?

[IvanK]

You are the one who started this thread regarding real world Spitfire stability. In your opening post you tell us all that this is to be a discussion on Spitfire stabilty:

"This thread is going to cover the definable and measure stability and control characteristics of the Spitfire. It is not going to cover opinion outside of stability and control engineers.

What this thread is not going to do:

1. Get into a debate about "easy to fly". It is not definable and has no bearing on the measured facts.

2. It is not going to discuss the sustained level turning ability of the aircraft. That is also measurable and definable. For Example, anyone who is capable of doing the math will see that the Spitfire outturns the Bf-109 is steady state constant altitude turns at low velocity."

You then decide its an item for the bugtracker which deals with Sim behaviour. bugtrqacker is for bugs. The onus is on YOU as the thread starter and intended Bug tracker author to prove there is an issue in game.... so far you have not.

When you do make sure its in a definable,measurable and to an accepted standard.

[Crumpp]

When you do make sure its in a definable,measurable and to an accepted standard.

IvanK, all of this is measured, defined, and easy to test in the game.

What question do you have on how to test it?

[IvanK]

None just eagerly awaiting the results of your tests.

[41Sqn_Banks]

http://zipmeme.com/uploads/generated/g1343631565227914996.jpg

[robtek]

One thing that isn't represented in game is the possibility to rip the wings of the Spitfire with a sudden stick movement of about 50% travel at cruise speed, exceeding 10 to 12g this way.

If that would be in game, 80% of bounced Spitfires would loose their wings as the instinctive reaction is to yank at the stick.

According to the tests and pilots handbook it should be that way.

If the wings aren't ripped off at least a immediate hi speed stall with a flick into a spin should occur.

That also isn't so in game, the Spitfire lateral controls are by far not sensible enough.

The ailerons then are too sensible.

[macro]

Do we know what 'g' a spit would break up at?

Interested as not seen this written anywhere. Will look later when home from work unless someone else is bored?

[IvanK]

Other than the Italian fighters (whose design load spec was amongst the highest of all nations in WWII), 12G Symmetrical would most likely result in some sort of structural damage/failure in pretty much any WWII fighter (and just about any current fighter as well). Rolling G damage would occur at very much lower values.

Structural G modelling is in IMO poorly modelled in CLOD and was the subject of debate before release.

This is thread drift though :)

Edit: Basic Spitfire Design load was 10G. Source : Spitfire at War vol I Ch 19 "Stronger, Safer Swifter" by Eric Newton MBE,Ceng,FRAes

[NZtyphoon]

One thing that isn't represented in game is the possibility to rip the wings of the Spitfire with a sudden stick movement of about 50% travel at cruise speed, exceeding 10 to 12g this way.

If that would be in game, 80% of bounced Spitfires would loose their wings as the instinctive reaction is to yank at the stick.

According to the tests and pilots handbook it should be that way.

If the wings aren't ripped off at least a immediate hi speed stall with a flick into a spin should occur.

That also isn't so in game, the Spitfire lateral controls are by far not sensible enough.

The ailerons then are too sensible.

Yeah right, now we are into the theatre of the absurd with claims that at least 80% of Spitfires would lose their wings because tests and the Spitfire Pilot's Notes say so. :rolleyes:

I guess that means that the NACA Spitfire V lost its wings or, at the very least, flicked into a high speed stall then spun. I don't see anything in the NACA tests showing this, nor do I see 80% of Spitfire pilots claiming that they lost control, went into a high speed stall and flicked into a spin - unless they were the ones who lost their wings.

[macro]

10g. Blimey thats past blackout isnt it? Will be ok i rarely push it that hard.

[Crumpp]

Blimey thats past blackout isnt it? Will be ok i rarely push it that hard.


Depends on the onset rate and exposure time.

You won't necessarily pass out in RoR (rapid onset rate).

GoR (gradual onset rate), you have been asleep for a while!!

[6S.Manu]

Yeah right, now we are into the theatre of the absurd with claims that at least 80% of Spitfires would lose their wings because tests and the Spitfire Pilot's Notes say so. :rolleyes:

He said "ingame", and he's right knowing the skill of many players out there (myself too): it's not a matter of plane, it's a matter of how hard they pull the stick. :rolleyes:

There was a problem in IL2 1946 v4.10 about the 190s' negative G-force: with the stick's linear setting at 100 you had not to push the stick at high speed at all since the wings would come off (many times it's happended to me and my teammates, and my main KIA reason): instead you could pull as you want.

If I understand correctly Robtek asks to have the same effect linked to the pull up manouvre in a Spitfire (but far weaker compared the one above, that was horrible and I noted that in HSFX6's Hellcats!): in this I fully agree with him.

[robtek]

The pilots notes warn explicit that ripping of the wings is possible if not carefully flown.

The short stick travel and low force needed to get high g-loads are undisputed, aren't they?

The manual even say that the pilot has to brace himself not to get pilot induced over-g in bumby conditions.

If one pulls the joystick half the way back that would be equal to about 6 inches in RL -> as there is 3/4 inch for a 3 g load, which will even climb when not released immediately, 6 inches would either snap the wing, or result in a hi-speed stall with following spin, and blackout.

Other planes, i.e. 109, where the stick force and travel (lateral) are larger by far, should't react this way, as it is now.

Generally, a longer stick travel gives the pilot much more fine control, here in the pitch axis, and that should be modeled.

[Crumpp]

Will be ok i rarely push it that hard.

All of this will be ok. Most of the fandom in this thread do not understand the big picture.

[NZtyphoon]

All of this will be ok. Most of the fandom in this thread do not understand the big picture.

Here we go again, Crumpp knows all while everyone else, apart from those who agree with him, know nothing.

[macro]

If this was moddeled by robtek explaination could we not just get round it by making the joystick half as sensitive, if you know what i mean.
It would give unfair advantage over109 astheres is limited by how far the stick can move instead of pilot overpulling it
I am a fan of the spit,, i dont know an englishman who isnt.

[winny]

Some info on bob/inertia weights fitted to Spitfires.

It was first trialled in the prototype MkIII, then a MkII

From everything I've read the reason it was fitted was that lots of pilot's were writing off airframes by overloading them. Bent wings were a bit of a reccuring theme. Caused in the majority of cases by pulling out of a high speed dive or too tight a turn.

In June 41 it was decided that all Mk V's should have inertia weights fitted.
3.5lb for a VA and 6.5lb for a VB

After RAE trials it was decided that all the following marks must have the 6.5lb weight fitted. Mks F VI, PR IV, VI and VII, Seafires I and II.

No weights needed for Mks I and II and V's, provided that with the browning only wing the rear oxygen cylinder was removed, and with the cannon wing the oxygen cylinder, signal discharger and IFF radio were removed.

In '42 a VB Merlin 45 (BM589) did handling and stability trials with special reference to pull out from dives and tight turns. Tested with and without 6.5 lb inertial weight. (This after reports from pilot's who did not like the inertia weight). The outcome was that it was suggested that the inertia weight only be fitted into aircraft (V's) with the Rotol prop.

The inertia weight was quite unpopular: Hornchurch reported "All pilot's are beginning to complain" Biggin Hill " Condemned for making Spitfire difficult to land and reducing manoeuvrability" Kenley "Did not notice effect of the weight but opinion of the Spitfire was in general, low" Tangmere "Do not care for the the device"

[robtek]

If this was moddeled by robtek explaination could we not just get round it by making the joystick half as sensitive, if you know what i mean.
It would give unfair advantage over109 astheres is limited by how far the stick can move instead of pilot overpulling it
I am a fan of the spit,, i dont know an englishman who isnt.

In this case one wouldn't have the full deflection needed for a three pointer or in a really slow turn, i think.

[Glider]

The pilots notes warn explicit that ripping of the wings is possible if not carefully flown.

The short stick travel and low force needed to get high g-loads are undisputed, aren't they?

The manual even say that the pilot has to brace himself not to get pilot induced over-g in bumby conditions.

If one pulls the joystick half the way back that would be equal to about 6 inches in RL -> as there is 3/4 inch for a 3 g load, which will even climb when not released immediately, 6 inches would either snap the wing, or result in a hi-speed stall with following spin, and blackout.

Other planes, i.e. 109, where the stick force and travel (lateral) are larger by far, should't react this way, as it is now.

Generally, a longer stick travel gives the pilot much more fine control, here in the pitch axis, and that should be modeled.

And there is no doubt that the pilots notes did what they were supposed to do, warn the pilots of potential issues and advise them how to avoid it. I did post a breaskdown of all the structural failures of Spits during the war

23,000+ spits built 121 failures, 22 due to a problem with fabric control surfaces, a number of others due to pilot error re use of oxygen, some due to engine fires.
How many flights do you think those 23,000 spits did during the war, no idea but easily in the millions. How many of those accidents were in training units again no idea but safe to assume a good proportion of the pilot error ones.

And you want to build something into the game to take the wings off in a tight pull up.

If you do this can we assume that you will agree to similar factors into the 109F and 109G both of which had serious issues with wing failure

[macro]

what i meant robtek was haveing different settings for the stick, say not very sensitive at near-center stick then more sensitive at the full back position, thus nulling out the intened sensitivity in the game whilst giving full range. The 109 wouldnt allow this as its modelled in game how the plane will move as it wasnt possible to pull the stick full back at speed as no pilot would have the strength to do so. basically an easy exploit (crap at explaining i know) :-P


surely putting enough g on any plane and the wings will fold, just need to know how much for each plane but i would have thought this be a bit down the line to do this sort of dm considering its current problems :mad:

[Holtzauge]

The pilots notes warn explicit that ripping of the wings is possible if not carefully flown.

The short stick travel and low force needed to get high g-loads are undisputed, aren't they?

The manual even say that the pilot has to brace himself not to get pilot induced over-g in bumby conditions.

If one pulls the joystick half the way back that would be equal to about 6 inches in RL -> as there is 3/4 inch for a 3 g load, which will even climb when not released immediately, 6 inches would either snap the wing, or result in a hi-speed stall with following spin, and blackout.

Other planes, i.e. 109, where the stick force and travel (lateral) are larger by far, should't react this way, as it is now.

Generally, a longer stick travel gives the pilot much more fine control, here in the pitch axis, and that should be modeled.

Sure you can pull the wings off but I don't think the data so far indicates it was a problem: Figure 12 b in the NACA Spitfire test gives the g-load gradient at 4.7 lb/g. Granted the curve does not go to really high g but assuming the gradient holds for higher loads as well and assuming a failure g-load of of 10-12 g that equates to a pull force of 47-56 lb needed to pull of the wings. So even if the actual deflection of the elevator was small you still needed quite a bit of hauling on the stick to pop the wings.

And remember that control without excessive deflection but by force input is practiced today: At the extreme was the F-16 which at some stage in development IIRC had a FIXED stick with no deflection at all. However, if memory serves me they had to introduce some some small deflection (1/16"?)in order to avoid PIO but essentially the control is by force input.

So frankly I do not see a problem if I need to pull all of 50-60 lb before the wings comes off: The porpoising that would result from flying in turbulence without wedging your arm would be annoying to be sure but you would hardly pull the wings off if you happen to sneeeze or fly through some rough air :)

[robtek]

And there is no doubt that the pilots notes did what they were supposed to do, warn the pilots of potential issues and advise them how to avoid it. I did post a breaskdown of all the structural failures of Spits during the war

23,000+ spits built 121 failures, 22 due to a problem with fabric control surfaces, a number of others due to pilot error re use of oxygen, some due to engine fires.
How many flights do you think those 23,000 spits did during the war, no idea but easily in the millions. How many of those accidents were in training units again no idea but safe to assume a good proportion of the pilot error ones.

And you want to build something into the game to take the wings off in a tight pull up.

If you do this can we assume that you will agree to similar factors into the 109F and 109G both of which had serious issues with wing failure

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

[Holtzauge]

You are the one who started this thread regarding real world Spitfire stability. In your opening post you tell us all that this is to be a discussion on Spitfire stabilty:

"This thread is going to cover the definable and measure stability and control characteristics of the Spitfire. It is not going to cover opinion outside of stability and control engineers.

What this thread is not going to do:

1. Get into a debate about "easy to fly". It is not definable and has no bearing on the measured facts.

2. It is not going to discuss the sustained level turning ability of the aircraft. That is also measurable and definable. For Example, anyone who is capable of doing the math will see that the Spitfire outturns the Bf-109 is steady state constant altitude turns at low velocity."

You then decide its an item for the bugtracker which deals with Sim behaviour. bugtrqacker is for bugs. The onus is on YOU as the thread starter and intended Bug tracker author to prove there is an issue in game.... so far you have not.

When you do make sure its in a definable,measurable and to an accepted standard.


+1

And let's not forget: "So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.07.18301+Hot Fix ?"

However, knowing Crumpp's modus operandi I'm sure he's preparing something lenghty with lot's of red underlined quotes to pounce on the wing fold issue in order to extricate himself from the embarrasing stability issue....

[Glider]

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

Actually it wasn't that easy to reach the limit and lose the wing, if it was, more would have crashed. There was an issue later in the war with the wings bending and some reinforcement was introduced but that was when the Spit was being used as a dive bomber with a 1,000 lb payload. I don't think we can blame the pre war designers for not thinking of that scenario. details are in the 2TAF series of books by C Shore

Its also noticable that when the limit was reached the wings tended to bend and let the pilot get home, not break and bury the pilot in a hole in the ground. The Spit was designed with more flexability than most aircraft of the time. That should also be covered

I hope you agree that the foibles should include what the Germans thought of the Spitfire. Easier to fly, very easy to take off and land as well as being faultless in the turn.

[NZtyphoon]

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

So, there's also room for replicating the Spitfire's desirable stall warning and stall characteristics

http://i91.photobucket.com/albums/k304/Major_Sharpe/SpitfireVAStallCharacteristics-page-003a.jpg

http://i91.photobucket.com/albums/k304/Major_Sharpe/SpitfireVAStallCharacteristics-page-004a.jpg

It was well known that the Fw 190 was apt to flip upside down and crash at lower altitudes while attempting to recover from a dive, so IL2 might as well replicate that characteristic as well.

[CaptainDoggles]

It was well known that the Fw 190 was apt to flip upside down and crash at lower altitudes while attempting to recover from a dive, so IL2 might as well replicate that characteristic as well.

Oh, you guys :rolleyes:

I love it how for some people this is a red vs blue argument, so they make jabs at the 190 as if to "stick it" to the "blue guys".

Go back through the thread; comes up all the time.

[NZtyphoon]

Oh, you guys :rolleyes:

I love it how for some people this is a red vs blue argument, so they make jabs at the 190 as if to "stick it" to the "blue guys".

Go back through the thread; comes up all the time.
:rolleyes:
Nope, I have nothing to do with red or blue - just pointing out that if Robtek wants to be consistent about aircraft control characteristics in IL2 replicating real life then there are lots of WW2 aircraft which had a problem with their handling.

[Sandstone]

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

If it was "comparatively easy to do", how is it that almost no pilots ever did it, even given the rushed training available in WWII?

[robtek]

If it was "comparatively easy to do", how is it that almost no pilots ever did it, even given the rushed training available in WWII?

The pilots did read the pilots notes for their machines :D :D :D

No, actually the overwhelming majority of those pilots had a sound survival instinct, lots of feedback from their bodys and their rides,
and, last but not least, some didn't dare to fly their aircraft so close to the edge that they were outperformed by technically lesser able planes with better pilots.

[NZtyphoon]

The pilots did read the pilots notes for their machines :D :D :D

No, actually the overwhelming majority of those pilots had a sound survival instinct, lots of feedback from their bodys and their rides,
and, last but not least, some didn't dare to fly their aircraft so close to the edge that they were outperformed by technically lesser able planes with better pilots.

This is techno-speak to say that there are very few examples of Spitfires actually breaking up in accord with the Pilot's Notes and Robtek's beliefs about what a dangerous aircraft it was: in real life the Spitfire gave plenty of warning of an impending stall, as noted by NACA, and few actually encountered the theoretical extreme conditions noted by the PNs.

[TomcatViP]

Actually it wasn't that easy to reach the limit and lose the wing, if it was, more would have crashed. There was an issue later in the war with the wings bending and some reinforcement was introduced but that was

A, B, C, D, E ... it makes 5 different wing design. All with strengthening or correcting some aero issues. I don't see how you can write that Glider. And note that at the end the late E wing shape was far from being Elliptical.

Such as saying that out of 22000 built only 121 crashed when your source explain clearly that the study was only about some Spits that had crashed on Britain soil and which causes were investigated.

[CaptainDoggles]

:rolleyes:
Nope, I have nothing to do with red or blue - just pointing out that if Robtek wants to be consistent about aircraft control characteristics in IL2 replicating real life then there are lots of WW2 aircraft which had a problem with their handling.

Yeah, there are lots. But this thread is about the Spitfire. You just "randomly chose" the 190, I'm sure.

Not because it was a German aircraft :rolleyes: gimme a break.

[Crumpp]

Keep the thread on topic and stop with the "red vs blue" baloney.

[FS~Phat]

Ditto.... getting the picture gents?????

[FS~Phat]

Thread open again.. gents please stay civil. Next time several of you will incur 5 point general infractions or worse if you cant keep it from getting personal.

[NZtyphoon]

Yeah, there are lots. But this thread is about the Spitfire. You just "randomly chose" the 190, I'm sure.

Not because it was a German aircraft :rolleyes: gimme a break.

As far as I can tell there are no rules against citing German aircraft as an example of potentially deadly flight characteristics - FYI four books I have bought in the last few months are on the Do 335, (http://www.amazon.com/Dornier-335-Arrow-Monogram-Monarch/dp/0914144529/) the Ar 234 (http://www.amazon.com/Monogram-Monarch-Arado-234-Blitz/dp/0914144510/) the Bf 110/Me 210 and 410 series (http://www.amazon.com/Messerschmitt-110-210-410-Illustrated/dp/0764317849/) and the JG26 war diaries pt 1 (http://www.amazon.com/JG26-War-Diary-Vol-1939-1942/dp/1898697523/), so attempting to claim anti-German bias on my part is a waste of time.

Back to the Spitfire - with all the claims being made that early marks of the Spitfire had bad longitudinal stability how did this show itself in real life? Apart from a set of pilot's notes and a NACA report, stating that it did not meet certain criteria, how much evidence exists of pilots complaining that they were nearly killed by a sudden, dangerous stall leading to a spin while pulling up in a tight turn? Are there any reports from Luftwaffe pilots stating that a Spitfire they had bounced lost its wings while trying to escape? Is there anything proving that Spitfires were destroyed between 1939 and 1941 because of bad longitudinal stability?

[ATAG_Dutch]

Thread open again.

http://www.youtube.com/watch?v=IKXEmXB7h3E

[Crumpp]

There were stories of Spit wings in huge piles at maintenance units as fractured wings were replaced after sharp pullouts at low levels

http://members.madasafish.com/~d_hodgkinson/hawker-Vspit.htm

[NZtyphoon]

http://members.madasafish.com/~d_hodgkinson/hawker-Vspit.htm

Oh wow a website :rolleyes: How 'bout some tangible, documented evidence to back up these stories?

Alex Henshaw's observations:

(Note Comment on Spitfire as gun platform)
http://i91.photobucket.com/albums/k304/Major_Sharpe/Henshaw12-page-003a.jpg

something not mentioned so far, possible maladjustment of the tailplane fairing shroud, which could affect the handling: of further note the Spitfire could safely be dived past the Vne set by Supermarine and noted in the Pilot's Notes.
http://i91.photobucket.com/albums/k304/Major_Sharpe/Henshaw13-page-001a.jpg

[Seadog]

There were stories of Spit wings in huge piles at maintenance units as fractured wings were replaced after sharp pullouts at low levels
http://members.madasafish.com/~d_hod...wker-Vspit.htm
http://members.madasafish.com/~d_hodgkinson/hawker-Vspit.htm

There are stories of Me109s that made large craters after they failed to pull out of dives, because the aircraft was too stable...:

Range of Investigation. – The handling tests covered the following ground : – ease of take-off and landing ; trim and stability ; " one control " tests, flat turns and sideslips ; stalling tests, including a determination of CLmax ; high-speed dive ; harmony and " feel " of the controls.

An investigation of the fighting qualities of the Me. 109 included dog fights with Hurricanes and Spitfires, measurement of aileron forces and times to bank at speeds up to 400 m.p.h., and an analysis of the turning performance of the aircraft.

Pilots' views on cockpit layout, comfort and view are given in an Appendix to the report.

Conclusions. – (i) Take-off is fairly straightforward. Landing is difficult until the pilot gets used to the aircraft.

Longitudinally the aircraft is too stable for a fighter. There is a large change of directional trim with speed. No rudder trimmer is fitted ; lack of this is severely felt at high speeds, and limits a pilot's ability to turn left when diving.

Fin area and dihedral are adequate. The stall is not violent, and there is no subsequent tendency to spin. CLmax is 1.4, flaps up and 1.9, flaps down. No vibration or " snaking " develop in a high-speed dive.

Aileron snatching occurs as the slots open. All three controls are far too heavy at high speeds. Aerobatics are difficult.

(ii) The Me. 109 is inferior as a fighter to the Hurricane or Spitfire. Its manoeuvrability at high airspeeds is seriously curtailed by the heaviness of the controls, while its high wing loading causes it to stall readily under high normal accelerations and results in a poor turning circle.

At 400 m.p.h. a pilot, exerting all his strength, can only apply 115 aileron, thereby banking 45 deg. in about 4 secs. From the results Kb, for the Me. 109 ailerons was estimated to be - 0.145.

The minimum radius of turn without height loss at 12,000 ft., full throttle, is calculated as 885 ft. on the Me. 109 compared with 696 ft. on the Spitfire...

...4.62. Elevator. – The elevator is an exceptionally good control at low speeds ; it is fairly heavy, and is not over sensitive during the approach glide, while response is excellent. Throughout the speed range the elevator is heavier than that of the Hurricane or Spitfire, but up to 250 m.p.h. this is not objected to, since it is very responsive. Above 250 m.p.h. the elevator becomes definitely too heavy for comfort, and between 300 m.p.h. and 400 m.p.h. is so heavy that maneuvrability in the looping plane is seriously restricted; when diving at 400 m.p.h. a pilot, pulling with all his strength, cannot put on enough g to black himself out if trimmed in the dive.
http://kurfurst.org/Tactical_trials/109E_UKtrials/Morgan.html
.

[robtek]

There are stories of Me109s that made large craters after they failed to pull out of dives, because the aircraft was too stable...:

.

Again Red vs Blue????

[bongodriver]

Again Red vs Blue????

Why is it red v blue?....AFAIK it's true, I'm not so sure what the apparent significance of an annecdote about Spitfire wings in piles is, presumably the aircraft returned home to have their wings replaced if it's true.

[macro]

Having a note saying wingss got damaged is no good for the game. Need to know the g limit numbers for the aircraft to model structural damage from manouvers, regardless of what plane it is. That should have its own thread to find them for each plane in the game?

[IvanK]

That data Macro is known. The issue is the FM doesnt really model structural G limits. DT have done this in IL2 4.10 and up.

[6S.Manu]

Why is it red v blue?....
It's amusing the fact that people need to bring on another plane (or better "those" other planes) to defend a plane issue clearly written in the pilot's notes book.

But it's not a Red vs Blue, of course...

At time we'll talk about those planes too...

presumably the aircraft returned home to have their wings replaced if it's true.

Of course the RTBed aircrafts would have the wings replaced, but why did they need to replace them? Couldn't them still fight in that condition? Or maybe it was an issue this sim needs to reproduce?

Since I'm not sure that a plane with overstressed wings can be effective in the way many virtual pilots are used to fly it. Instead I'm sure that a plane with a damaged wings' structure will not fly as it did before and the pilot needs to take it back ASAP... above all if it's a high performance fighter!

If we make a mistake, pulling up too much so that the wings' structure is damaged (even if not critically) and we are enought lucky and the wings are still there does not mean that we can fight as nothing is happened.

It's an issue of every plane, and it should be simulated correctly: then there are planes more prone to this problem (the ones with sensitive elevator maybe?).

From the pilot's notes:
Diving: The aeroplane becomes very tail heavy at high speed and must be trimmed into the dive in order to avoid the danger of excessive acceleration in recovery. The forward trim should be wound back as speed is lost after pulling out.

I don't recall to do it in any simulator... If I trim it's only to keep the nose on the target, not because of a probable structure damage. Probably only in IL2 1946 after the DT's work.. but only in planes carrying a heavy load.

Then we can talk about the effect of a slightly damaged wings' structure on the plane, but it's another matter: it's still sure that it's not a good thing for a fighter (until the new myth "Spitfires could fly at full performance even with damaged wings!")

[NZtyphoon]

Again Red vs Blue????

Again, as far as I can tell there are no rules in this forum against citing German aircraft as an example of potentially deadly flight characteristics. ;)

A whole generation of pilots learned to treasure the Spitfire for its delightful response to aerobatic manoeuvres and its handiness as a dogfighter. Iit is odd that they had continued to esteem these qualities over those of other fighters in spite of the fact that they were of only secondary importance tactically.Thus it is doubly ironic that the Spitfire’s reputation would habitually be established by reference to archaic, non-tactical criteria.

What this doesn't say is that pilots who have trust and confidence in the handling and capabilities of their aircraft will carry that confidence into battle, which, in itself of tactical value. Secondly, the claim that aerobatic manoeuvres and handiness as a dogfighter are somehow tactically archaic flies in the face of modern fighters such as the Su-27 or F-16 or F-22 which were deliberately designed to be good at aerobatics and be handy in a dogfight, if need be.

[bongodriver]

Of course the RTBed aircrafts would have the wings replaced, but why did they need to replace them? Couldn't them still fight in that condition? Or maybe it was an issue this sim needs to reproduce?



You miss the point, it's been a claim since the beginning of this thread that Spits broke up in flight, now it's come down to piles of wings, both theories are pure anecdotes and have no proof whatsoever.....so what is it? do they break up? or do they just bend wings?......or is it in fact neither because the apparent problem is all a fabrication?.....my vote is the latter because it is clear this thread is about nothing more than a desparate attempt to pork the Spit, there won't be a 109 thread...not from the OP anyway.....I see no reason one couldn't have been started already.....well the reason is actually obvious, it avoids bringing unwanted attention to the favoured aircraft, people can just rip the Spit to shreds and make all the accusations of Spit 'fanboys' or red v blue agendas in the Spit thread.

[6S.Manu]

What this doesn't say is that pilots who have trust and confidence in the handling and capabilities of their aircraft will carry that confidence into battle, which, in itself of tactical value.
Having confidence in the plane is a lot different from confidence in yourself... confidence in the machine is the one who kills you... it's one of the reason people get killed in motor accidents.


Secondly, the claim that aerobatic manoeuvres and handiness as a dogfighter are somehow tactically archaic flies in the face of modern fighters such as the Su-27 or F-16 or F-22 which were deliberately designed to be good at aerobatics and be handy in a dogfight, if need be.

That statement it's clearly referred to the WW2, when it's WAS archaic.

[NZtyphoon]

Having confidence in the plane is a lot different from confidence in yourself... confidence in the machine is the one who kills you... it's one of the reason people get killed in motor accidents.

I would really like to see some evidence of this being true and that it isn't just a piece of pop-psychology.

That statement it's clearly referred to the WW2, when it's WAS archaic.

Who said it and why? Ahhh, found it (http://www.darwinspitfires.com/articles/spitfire-vc-versus-the-zero.html) and, wouldn't you know it, it is being used in the context of the Spitfire VC v A6M2 over Darwin, when RAAF pilots discovered trying to out manœvre an aircraft which was even more manœvreable and handy in a dogfight was tactically futile. What it also states is:

It was only at higher speeds that the Spitfire started to enjoy a relative advantage. Because the Zero’s controls stiffened up even more rapidly than the Spitfire’s, the Zero had great difficulty in following the Spitfire through high speed manoeuvres where the pilot pulled a lot of G. From about 290 knots, the Zero had great difficulty following the Spitfire through diving aileron rolls. The conclusion was that the Spitfire was more manoeuvrable above 220 knots, while the Zero was the better below that speed.

[6S.Manu]

You miss the point, it's been a claim since the beginning of this thread that Spits broke up in flight, now it's come down to piles of wings, both theories are pure anecdotes and have no proof whatsoever.....so what is it? do they break up? or do they just bend wings?......or is it in fact neither because the apparent problem is all a fabrication?.....my vote is the latter because it is clear this thread is about nothing more than a desparate attempt to pork the Spit, there won't be a 109 thread...not from the OP anyway.....I see no reason one couldn't have been started already.....well the reason is actually obvious, it avoids bringing unwanted attention to the favoured aircraft, people can just rip the Spit to shreds and make all the accusations of Spit 'fanboys' or red v blue agendas in the Spit thread.
Warning on pilot's notes are not a fabrication.

According the numbers posted by Glider (even if they're from an limited investigation on only 121 accidents... a small sample of course) the 38% of those planes were lost for a overstressed airframe issue.

The next most serious cause of structural failure in the Spitfire was pilots overstressing the airframe. She was extremely responsive on the controls and one must remember that in those days there was no accelerometer to tell the pilot how close he was to the limit. So it was not difficult to exceed the aircraft's 10G ultimate stress factor during combat or when pulling out from a high speed dive; during the war we were able to put down 46 major accidents to this cause, though undoubtedly there were many other occasions when it happened and we did not see the wreckage. Incidentally, if there was a structural failure in the Spitfire it was almost inevitably the wing that went; the fuselage was far less likely to fail first (the same for most low wing monoplane fighters?-except the Typhoon?- Berkshire).
Is it an OP's fabrication?

Do you really think that this kind of issue has not to be simulated? On all the planes, of course.

I see no reason one couldn't have been started already.....well the reason is actually obvious, it avoids bringing unwanted attention to the favoured aircraft
Really?

- 109's fans want to talk about Spitfire to avoid attention on their plane
- Spitifire's fans want to talk about 109 to avoid attention on their plane

Great logic IMO.
Can you suggest a plane to talk about to avoid attention on the P51 (my favourite plane with the 190)?

Why can't we admit that those were high performance fighters and everyone of these had some issues? We should just take note of that to have a realistic sim and then we can start to analyze another plane.

Let's do it in a mature way... in this thread there are to many childish reactions and it's clear that all is created by the same few posters who keep fighting in every WW2 message board of the web.

[robtek]

You guys remember the topic of this thread, don't you?
It's about ONE specific plane and that one only.
Stop digressing.

[bongodriver]

Warning on pilot's notes are not a fabrication.



They are simply warnings, not an indication of a particular dangerous characteristic....you know like 'always wear safety glasses'


According the numbers posted by Glider (even if they're from an limited investigation on only 121 accidents... a small sample of course) the 38% of those planes were lost for a overstressed airframe issue.



So 38% of 121 investigations is proof?, it just means that from an already tiny amount less than half were attributable to airframe failure.


Is it an OP's fabrication?



What the OP is fabricating is a larger problem, nobody claims 'no' Spitfires ever 'broke up', if you really wanted to you could 'break' any aircraft through overstress and the Spitfire was not notorious for it, just because it had sensitive elevators that 'could' do it it doesn't mean that it was a regular occurrence, the OP almost seems to be insisting that these problems should become apparent during normal operating ranges of speed and manouvers......I wonder why:rolleyes:


Really?

- 109's fans want to talk about Spitfire to avoid attention on their plane
- Spitifire's fans want to talk about 109 to avoid attention on their plane



Yep....why didn't we get a 109 thread first?


Great logic IMO.
Can you suggest a plane to talk about to avoid attention on the P51 (my favourite plane with the 190)?


if they had anything to do with the BoB scenario in Cliffs of Dover.


Why can't we admit that those were high performance fighters and everyone of these had some issues? We should just take note of that to have a realistic sim and then we can start to analyze another plane.



When did anybody deny it?....sooo in order to have a realistic sim we must first make the Spit useless? then we can make the rest accurate?


Let's do it in a mature way... in this thread there are to many childish reactions (where the worst is blamimg other guys to be anti-British) and it's clear that all is created by the same few posters who keep fighting in every WW2 message board of the web.


I'd like you to delete the bit in bold, or I will have to complain as I find it offensive.

[macro]

Ivan can you point me to that info i couldnt find it

[6S.Manu]

I would really like to see some evidence of this being true and that it isn't just a piece of pop-psychology.

Can I said the same thing about your first statement?

It's easy to realize that the probability to make mistakes is bigger doing "easy" things, while people are more careful doing things who can have unforgivable reactions.

It's called overconfidency. The easier is the task, the bigger is the probabilty of overconfidence.

http://www.readperiodicals.com/201201/2592264861.html

When I would come home, conversations between my Dad and I would frequently drift to flying and his stories about friends he had lost in training and in combat meant even more to me. I too was seeing many pilots, very good pilots, make fatal mistakes. A lot of our discussions centered on the bad attitudes that can get one in trouble in the flying business: complacency, "get-home-itis," pressing minimum altitudes or separation distances, and overconfidence. The last one, overconfidence, intrigued me. As a young single-seat fighter pilot, I knew I needed to be confident in my skills to fly the airplane as aggressively as the situation required. But how could too much confidence in my skills get me in trouble?

As a 2Lt copilot in a B-26, my Dad's experienced and overconfident aircraft commander got too slow trying to climb over the top of a thunderstorm. He stalled the aircraft and put it into a flat spin. Only my Dad and one other crew member survived. Forty years later, when I was a 2Lt, one of my best friends was an extremely talented pilot and arguably had some of the best "hands" in the squadron. But his overconfidence bordered on recklessness, and it eventually killed him. As a single-seat fighter pilot, I knew I needed to be sure of my ability to fly the airplane, but I was determined to not let myself get overconfident and put myself in an untenable situation.

About my statement I realize that it's wrong, and I wrote something different from what I initially wanted... and still I'm not finding a way to put it down firstly in my first language.

Anyway It's OT.


Who said it and why? Ahhh, found it (http://www.darwinspitfires.com/articles/spitfire-vc-versus-the-zero.html) and, wouldn't you know it, it is being used in the context of the Spitfire VC v A6M2 over Darwin, when RAAF pilots discovered trying to out manœvre an aircraft which was even more manœvreable and handy in a dogfight was tactically futile.
Don't change argument: it's not a statement related to the plane model... it's a general one about WW2 air warfare.

Anyway I love the way you keep posting only the parts that follow your agenda even if there are noone contesting it: it's a Zero's known issue the one about its high speed manouvrability...

Ah.., sorry I forgot: it's the "Look how better is my plane" agenda.

[bongodriver]

Ah.., sorry I forgot: it's the "Look how better is my plane" agenda


This is becoming trolling...

[6S.Manu]

Yep....why didn't we get a 109 thread first?

Do we have to make a poll do decide which plane is the first one to be analysed? Above all by a person who actually does it for free and it's not one of our employers?

I've not problem on which one is the first plane... we have to start from something.


When did anybody deny it?....sooo in order to have a realistic sim we must first make the Spit useless? then we can make the rest accurate?

Why useless? Does realistic mean useless?

You say "then"... if a new feature is been added to the FM engine I expect it to be modelled in every plane... implementing a new v2.0 FM for a model leaving the other plane with the v1.0 is not a professional way to act... of wait.. about IL2 I remember new Lods against old ones... I don't want something like that.


I'd like you to delete the bit in bold, or I will have to complain as I find it offensive.
It's not about you... it's about a guy who I put into my ignore list since I was being anti-British claiming that the Spitfire myth is partially born because it's a simbol of the British's win. As P51 for the americans, T34 for the russian ect. does that make me an anti-american and anti-russian?

This is becoming trolling...
Please explain to me what is the reason to quote that the Spitfire was more manouvrable of the Zero at high speed... above all when the argument was totally another one.

[Crumpp]

They are simply warnings, not an indication of a particular dangerous characteristic....you know like 'always wear safety glasses'


Completely, absolutely, utterly false and extremely dangerous attitude.

Engineering tolerances are naturally tight due to the physics of flight. The POH instructions are part of the airworthiness of the design.

In the famous 100 Octane thread, I posted the convention that makes compliance a legal issue. The Operating Instructions carry the weight of law from the aviation authority of the convention signer. Only by explicit instruction is deviation authorized. An example of that explicit instruction is found in the RAF General Pilot's Operating Notes.

Statistically, deviation from those instruction is a factor in the vast majority of aviation accidents whether the deviation, such as the allowance for combat in the RAF General Pilot's Notes, is authorized or not.


All of this is off topic. Start another thread if you want to discuss POH compliance issues.

[NZtyphoon]

Please explain to me what is the reason to quote that the Spitfire was more manouvrable of the Zero at high speed... above all when the argument was totally another one.

The subject of this thread is directly related to the Spitfire's flight qualities, so pointing out that at high speed it could outmanœvre one of the most manœverable fighters of its generation is perfectly reasonable in the context of the discussion, so take your own advice and do this in a mature way.

Once again there are no forum rules stopping anyone from posting comments on the flight qualities of German, Japanese or Italian aircraft.

[bongodriver]

Completely, absolutely, utterly false and extremely dangerous attitude.



only if you decide to ignore the warning and 'not' wear the safety glasses.

[6S.Manu]

Completely, absolutely, utterly false and extremely dangerous attitude.

Engineering tolerances are naturally tight due to the physics of flight. The POH instructions are part of the airworthiness of the design.

In the famous 100 Octane thread, I posted the convention that makes compliance a legal issue. The Operating Instructions carry the weight of law from the aviation authority of the convention signer. Only by explicit instruction is deviation authorized. An example of that explicit instruction is found in the RAF General Pilot's Operating Notes.

Statistically, deviation from those instruction is a factor in the vast majority of aviation accidents whether the deviation, such as the allowance for combat in the RAF General Pilot's Notes, is authorized or not.


All of this is off topic. Start another thread if you want to discuss POH compliance issues.

Sorry fot the OT Crumpp, but I think that there's nothing more to talk about in this threat.

Are you planning to open a new one for the 109? I'm really interested about it!

[bongodriver]

Do we have to make a poll do decide which plane is the first one to be analysed? Above all by a person who actually does it for free and it's not one of our employers?.

Employers?

Who said anything about a poll?....there you go making bizarre statements again, I'm just saying it's no coincidence that the issue started with the Spitfire and I gave the reasons why.

I've not problem on which one is the first plane... we have to start from something.

easy to say

Why useless? Does realistic mean useless?.

Lets see, it has to be so unstable that only very skilled pilots can fly it, it must break up if you do a hard manouver, it must have very dangerous stall/spin characteristics, it must have bad turning characteristics against a 109.....all of this has had evidence to show it's not true but because of one guy and his NACA report on a different variant everybody thinks it was written by god?

You say "then"... if a new feature is been added to the FM engine I expect it to be modelled in every plane... implementing a new v2.0 FM for a model leaving the other plane with the v1.0 is not a professional way to act... of wait.. about IL2 I remember new Lods against old ones... I don't want something like that..

Whaa?

It's not about you... it's about a guy who I put into my ignore list since I was being anti-British claiming that the Spitfire myth is partially born because it's a simbol of the British's win. As P51 for the americans, T34 for the russian ect. does that make me an anti-american and anti-russian?.

I still find the statement offensive...please remove it, at least I'm being 'grown up' about it and giving the opportunity....not a courtesy extended to myself very often.

Please explain to me what is the reason to quote that the Spitfire was more manouvrable of the Zero at high speed... above all when the argument was totally another one.

Constant accusations of having a red v blue agenda are apparently trolling.....unless it's an accusation coming from the blue side apparently.

[Crumpp]

Sorry fot the OT Crumpp, but I think that there's nothing more to talk about in this threat.


I think you are right. I will get the bugtracker posted. Been busy at work.

I would like to the do the Hurricane next but will leave it open to what the community wants to do.

Granted, the Hurricane will probably be a short thread as it does not have the emotional response of the Spitfire and its stability and control is not so dramatic as the Spitfire's.

[6S.Manu]

@Bongo: I'll reply by PM ;-)

I think you are right. I will get the bugtracker posted. Been busy at work.

I would like to the do the Hurricane next but will leave it open to what the community wants to do.

Granted, the Hurricane will probably be a short thread as it does not have the emotional response of the Spitfire and its stability and control is not so dramatic as the Spitfire's.

I hope it to be about the 109, so that everybody is going be satisfied.

[Al Schlageter]

I hope it to be about the 109, so that everybody is going be satisfied.

That would be the natural choice, so one has to wonder why another British a/c.;)

[bongodriver]

@Bongo: I'll reply by PM ;-)



I hope it to be about the 109, so that everybody is going be satisfied.

Reply to what?......still nothing received.

don't hold your breath hoping, Crumpp will never make a 109 thread, by the time the Hurri one is done he will say it's all not worth the effort because of red fanboys etc etc....

p.s. still waiting for you to remove the comment.

[Seadog]

I think you are right. I will get the bugtracker posted. Been busy at work.

I would like to the do the Hurricane next but will leave it open to what the community wants to do.

Granted, the Hurricane will probably be a short thread as it does not have the emotional response of the Spitfire and its stability and control is not so dramatic as the Spitfire's.


Why not a thread on the deadly stability and control issues of the Me109?

Range of Investigation. – The handling tests covered the following ground : – ease of take-off and landing ; trim and stability ; " one control " tests, flat turns and sideslips ; stalling tests, including a determination of CLmax ; high-speed dive ; harmony and " feel " of the controls.

An investigation of the fighting qualities of the Me. 109 included dog fights with Hurricanes and Spitfires, measurement of aileron forces and times to bank at speeds up to 400 m.p.h., and an analysis of the turning performance of the aircraft.

Pilots' views on cockpit layout, comfort and view are given in an Appendix to the report.

Conclusions. – (i) Take-off is fairly straightforward. Landing is difficult until the pilot gets used to the aircraft.

Longitudinally the aircraft is too stable for a fighter. There is a large change of directional trim with speed. No rudder trimmer is fitted ; lack of this is severely felt at high speeds, and limits a pilot's ability to turn left when diving.

Fin area and dihedral are adequate. The stall is not violent, and there is no subsequent tendency to spin. CLmax is 1.4, flaps up and 1.9, flaps down. No vibration or " snaking " develop in a high-speed dive.

Aileron snatching occurs as the slots open. All three controls are far too heavy at high speeds. Aerobatics are difficult.

(ii) The Me. 109 is inferior as a fighter to the Hurricane or Spitfire. Its manoeuvrability at high airspeeds is seriously curtailed by the heaviness of the controls, while its high wing loading causes it to stall readily under high normal accelerations and results in a poor turning circle.

At 400 m.p.h. a pilot, exerting all his strength, can only apply 115 aileron, thereby banking 45 deg. in about 4 secs. From the results Kb, for the Me. 109 ailerons was estimated to be - 0.145.

The minimum radius of turn without height loss at 12,000 ft., full throttle, is calculated as 885 ft. on the Me. 109 compared with 696 ft. on the Spitfire...

...4.62. Elevator. – The elevator is an exceptionally good control at low speeds ; it is fairly heavy, and is not over sensitive during the approach glide, while response is excellent. Throughout the speed range the elevator is heavier than that of the Hurricane or Spitfire, but up to 250 m.p.h. this is not objected to, since it is very responsive. Above 250 m.p.h. the elevator becomes definitely too heavy for comfort, and between 300 m.p.h. and 400 m.p.h. is so heavy that maneuvrability in the looping plane is seriously restricted; when diving at 400 m.p.h. a pilot, pulling with all his strength, cannot put on enough g to black himself out if trimmed in the dive.
http://kurfurst.org/Tactical_trials/109E_UKtrials/Morgan.html
.

[Glider]

Warning on pilot's notes are not a fabrication.

According the numbers posted by Glider (even if they're from an limited investigation on only 121 accidents... a small sample of course) the 38% of those planes were lost for a overstressed airframe issue.

It is not a limited investigation on only 121 accidents... a small sample of course
Please read the posting again. These were all the accidents from the beginning of 1941 until the end of the war.

There were 121 Spitfire crash investigations between 1941 and May 1945 involving serious structural failure:
22 aileron instability #
46 pilot overstressed airframe
20 pilot error in cloud
13 misuse of oxygen system- pilot error #
3 pilot blacked out #
17 engine failure/fire #

Those marked # cannot be blamed on the airframe
Which leaves 66 where the airframe was a factor out of 23,000+ built during the war and millions of flights
Of those 66 a number would have been when the aircraft were in training units number unknown. I am confident that you would be hard pushed to find a lower accident rate of any front line fighter of any Air Force

The number of 121 matches the losses in Morgan and Shacklady recognised book on the subject so we have two different sources. Also note that the author worked in the accident branch which is independent form the RAF

If you wish to state that I have incorrect figures you had better support that comment.





Let's do it in a mature way... in this thread there are to many childish reactions and it's clear that all is created by the same few posters who keep fighting in every WW2 message board of the web.

I certainly agree that it should be a mature debate, with evidence to support any statement. So I await with some interest your explanation of how you determined that this was a small sample.

[Glider]

People keep mentioning the problems the SPitfire had with the wings bending and having to be replaced as proof of the weakness of the Spitfires wings. As I have said before this did happen but it happened in the last 12 months of the war when the Spit was being used as a dive bomber with 1,000lb payload. Details are in the C SHores books on the 2TAF.
This was fixed with some changes in tactics and the clipping of the wings.

I attach a paper that supports this view. If anyone believes that this was a common situation earlier in the war I invite them to provide similar evidence.

Please note that this happens with a full bomb load (1,000 lb) and the extra rear internal fuel tank. Obviously neither of these were around until late 1944

[6S.Manu]

It is not a limited investigation on only 121 accidents... a small sample of course
Please read the posting again. These were all the accidents from the beginning of 1941 until the end of the war.

I certainly agree that it should be a mature debate, with evidence to support any statement. So I await with some interest your explanation of how you determined that this was a small sample.

The interview start with:
"Out of a total of 121 serious or major accidents to Spifires reported to us between the begining of 1941 and the end of the war, 68 involved structural failure in the air. Initially the most common reason for such failures, with 22 instances in 1941 and 1942, was aileron instability. The symptoms were not at all clear cut: the aircraft were usually diving at high speed when they simply fell to pieces."

And finishes with:
"a total of more than 22,000 were built, and we were called in on only 130 occasions"

Maybe I'm reading wrong, you know, but it does not state they were all the Spitfire's accidents during all the war... they are the ones reported to the Air Accident Investigation Branch.

Does this imply these were all the accidents regarding this kind of plane?
Could be that sometimes an investigation was not necessary?
What about accidents over the Channel and France, where they couldn't analyse the wrecks?

[Glider]

The interview start with:
"Out of a total of 121 serious or major accidents to Spifires reported to us between the begining of 1941 and the end of the war, 68 involved structural failure in the air. Initially the most common reason for such failures, with 22 instances in 1941 and 1942, was aileron instability. The symptoms were not at all clear cut: the aircraft were usually diving at high speed when they simply fell to pieces."
If you read the whole piece the next few lines gives the details:-

Only after one of the pilots had survived this traumatic experience and parachuted successfully were we able to find the cause. During his dive he saw both of his ailerons suddenly flip up, producing an extremely violent pitch- up which caused the wing to fail and the aircraft to break up. In collaboration with RAE we did a lot of tests and found that aileron up- float was made possible by stretch in the control cables; in those days tensioning was a hit or miss affair with no compensation for temperature. On our recommendation the RAF introduced a tensometer which ensured accurate tensioning of the controls; this, and the simultaneous introduction of metal surfaced ailerons ('42/'43), cured almost all the cases of aileron instability in the Spitfire


And finishes with:
"a total of more than 22,000 were built, and we were called in on only 130 occasions"

Maybe I'm reading wrong, you know, but it does not state they were all the Spitfire's accidents during all the war... they are the ones reported to the Air Accident Investigation Branch.

You are reading that bit right but you also miss the bit where it says:-

Mr Newton was called in to investigate Spitfire crashes which could not be immediately attributed to pilot error (the same crashes which are detailed in Morgan and Shacklady).

Morgan and Shacklady is a very detailed book that details the history of the Spitfire including an entry for every SPitfire built. The number that the writer gives and the number in the Morgan and Shacklady book give for this type of incident match.

So we have two sources with the same number. Plus the Air Investigation branch are there for a reason. If you are in command of a unit of any type of aircraft and your planes start coming apart you will want to know why, so it isn't unreasonable to to expect losses of this type to be reported.

If you have better sources of information then put them forward, but until that moment I suggest this figure is as good as you are going to get.

I did have a breakdown as to when these incidents happened but cannot find it right now so cannot prove this next statement but the number that happened in training units was around 60-65% but I do put a caviet on that number but it wouldn't be unexpected.


Does this imply these were all the accidents regarding this kind of plane?
Could be that sometimes an investigation was not necessary?
I can only say yes to the best of my knowledge for the reasons stated. As for the second part I cannot say but its unlikely unless someone has repeated a mistake and they know the reason and the numbers do match

[robtek]

Those 130 accidents also don't include those losses, where after a few insignificant machine gun hits, or even only tracers around the cockpit, the pilot overreacted and went in with his ride because of over-g or a spin, which shurely has happened a few times.

It shurely then was accounted under losses because of enemy action.

There were quite a lot Spitfires lost during the BoB and not all had been shot to pieces.

And glider, nobody has said anything about the Spitfire being weak!!!

Only that the Spitfire controls made it relatively easy to reach the structural limits.

[6S.Manu]

Of course Glider, but I wanted you to focus on the bolded part. :-)

That "reported to us" is what gives me doubt about the numbers of total accidents.

It should be really interesting to read those reports: we ignore the investigation's method of the AABI and of course if, as you say, the known accidents were investigated again.

[DC338]

The essential problem and the neglected for most of this thread is how do you simulate it?

I think all sides would agree that the Spitfire had sensitive elevator controls. The degree of problem to the pilot is the issue. Yet with a simulator you have other issues that help or hinder the issue.

1.The problem is how do you simulate that in a game where control curves can be altered?

2.How do you simulate it in a game where you don't have the same control type as the real aircraft, with the same type and length of stick.

3.How do you simulate the different trim types. Some had stab trim which suits a return to center type arrangement such as the joysticks we all use. The majority however had trim tabs that change the stick position. how do you accountant for that in the sim? The shifting of the control curve as mentioned above.

4. How do you simulate the tactit feedback that a pilot gets in relation to G and buffet.

5. Who decides how strong the pilot is. This will become the issue when taking about aircraft with "heavy" controls. Heavy to whom.

This thread of 60 odd pages is like a merry go round.

To discuss the issue without addressing how you would simulate and the issues surrounding doing that, is a waste of %%(#ing time and energy.

You are arguing about degrees yet essentially want the same thing, accuracy. "forest for the trees" comes to mind. This is such a small issue in a sim that has much bigger problems, like aircraft not performing to spec.

[NZtyphoon]

Those 130 accidents also don't include those losses, where after a few insignificant machine gun hits, or even only tracers around the cockpit, the pilot overreacted and went in with his ride because of over-g or a spin, which shurely has happened a few times.

It shurely then was accounted under losses because of enemy action.

There were quite a lot Spitfires lost during the BoB and not all had been shot to pieces.

How many other aircraft types spun in because of pilots over-reacting and getting into trouble? We not yet seen any documented evidence that the Spitfire was more prone to this than other aircraft types, nor has there been any evidence posted of (say) Luftwaffe pilots/aircrew witnessing Spitfires losing their wings during combat. Without such evidence speculation about how many Spitfires might have crashed is just that - unsubstantiated speculation.

And glider, nobody has said anything about the Spitfire being weak!!!

Only that the Spitfire controls made it relatively easy to reach the structural limits.

Which is why we have undocumented stories, found on a single website, about stacks of buckled Spitfire wings. Read Henshaw's comments about the Spitfire's limits. Although Crumpp assumes that engineers were the most reliable people to assess the theoretical flight qualities of aircraft, pilots in the frontline and involved in the actual development of the aircraft have a far better idea of the real capabilities of the machine.

The essential problem and the neglected for most of this thread is how do you simulate it?

I think all sides would agree that the Spitfire had sensitive elevator controls. The degree of problem to the pilot is the issue. Yet with a simulator you have other issues that help or hinder the issue.

1.The problem is how do you simulate that in a game where control curves can be altered?

2.How do you simulate it in a game where you don't have the same control type as the real aircraft, with the same type and length of stick.

3.How do you simulate the different trim types. Some had stab trim which suits a return to center type arrangement such as the joysticks we all use. The majority however had trim tabs that change the stick position. how do you accountant for that in the sim? The shifting of the control curve as mentioned above.

4. How do you simulate the tactit feedback that a pilot gets in relation to G and buffet.

5. Who decides how strong the pilot is. This will become the issue when taking about aircraft with "heavy" controls. Heavy to whom.

This thread of 60 odd pages is like a merry go round.

To discuss the issue without addressing how you would simulate and the issues surrounding doing that, is a waste of %%(#ing time and energy.

You are arguing about degrees yet essentially want the same thing, accuracy. "forest for the trees" comes to mind. This is such a small issue in a sim that has much bigger problems, like aircraft not performing to spec.

+1

[robtek]

The essential problem and the neglected for most of this thread is how do you simulate it?

I think all sides would agree that the Spitfire had sensitive elevator controls. The degree of problem to the pilot is the issue. Yet with a simulator you have other issues that help or hinder the issue.

1.The problem is how do you simulate that in a game where control curves can be altered?

2.How do you simulate it in a game where you don't have the same control type as the real aircraft, with the same type and length of stick.

3.How do you simulate the different trim types. Some had stab trim which suits a return to center type arrangement such as the joysticks we all use. The majority however had trim tabs that change the stick position. how do you accountant for that in the sim? The shifting of the control curve as mentioned above.

4. How do you simulate the tactit feedback that a pilot gets in relation to G and buffet.

5. Who decides how strong the pilot is. This will become the issue when taking about aircraft with "heavy" controls. Heavy to whom.

This thread of 60 odd pages is like a merry go round.

To discuss the issue without addressing how you would simulate and the issues surrounding doing that, is a waste of %%(#ing time and energy.

You are arguing about degrees yet essentially want the same thing, accuracy. "forest for the trees" comes to mind. This is such a small issue in a sim that has much bigger problems, like aircraft not performing to spec.

For #1, dont make the controls adjustable, the pilot has to adapt to the plane, not the other way around.(only in game adjustments for axes, no native software)

#2, calculate the difference from the different steering columns to a average joystick and use this values for all.

#3, can't be simulated at the moment, same for all, no advantage for anyone.

#4, buffet can be simulated with head shake and g with increasing tunnel vision.

#5, must be 'Joe Average' for all pilots, in a few years maybe a body scan and a computerized fitness test in the setup. :D :D :D (With the body scan some pilots i know couldn't fly 109's anymore :D :D :D)

Just a few ideas, because it is easy to come up with problems, less so with solutions.

[ACE-OF-ACES]

So in summary..

Assuming this is even true..

This is NOT a bug!

It is a limitation of a simulation running on a PC and it associated hardware

Granted, with enough money this could be simulated, and similar things are in million dollar military and commercial simulators

But most of the CoD users can NOT even afford a decent video card, so god knows they are not going to shell out the money for the hardware to simulate this

Long story short, calling this a bug is just not accurate

[CaptainDoggles]

If it's just a limitation of PC hardware, why have you and your cronies been fighting this issue tooth and nail for 70 pages?
If the developers will never implement it, why have you and your cronies been fighting this issue tooth and nail for 70 pages?
If there are more important things to fix, why have you and your cronies been fighting this issue tooth and nail for 70 pages?

The vicious lashing out against this issue and people who support realism in this regard has been eye-opening to say the least.

[NZtyphoon]

For #1, dont make the controls adjustable, the pilot has to adapt to the plane, not the other way around.(only in game adjustments for axes, no native software)

#2, calculate the difference from the different steering columns to a average joystick and use this values for all.

#3, can't be simulated at the moment, same for all, no advantage for anyone.

#4, buffet can be simulated with head shake and g with increasing tunnel vision.

#5, must be 'Joe Average' for all pilots, in a few years maybe a body scan and a computerized fitness test in the setup. :D :D :D (With the body scan some pilots i know couldn't fly 109's anymore :D :D :D)

Just a few ideas, because it is easy to come up with problems, less so with solutions.

It will be the developers, not the one posting the bug-tracker, who have to make all of these calculations - assuming that there is a uniformity of equipment, and even player styles throughout the IL2 community - while trying to deal with all of the other bugs flowing into the bug-tracker report. I can just see them lining up pleading to tackle this so-called issue...:cool:

[CaptainDoggles]

It will be the developers, not the one posting the bug-tracker, who have to make all of these calculations - assuming that there is a uniformity of equipment, and even player styles throughout the IL2 community - while trying to deal with all of the other bugs flowing into the bug-tracker report. I can just see them lining up pleading to tackle this so-called issue...:cool:

See my previous post, then. If they're not going to fix it, why have you and your cronies been fighting so hard against it?

[bolox]

I was staying out of this thread but joysticks/control hardware is something i'm very interested in, See http://forum.1cpublishing.eu/showthread.php?t=29958
As much as anyone I want 'as realistic as possible' control behaviour, however I see some problems:-

For #1, dont make the controls adjustable, the pilot has to adapt to the plane, not the other way around.(only in game adjustments for axes, no native software)


Bit of a problem here as not all sticks have the same response.
Expensive sticks can have the ability to change curves outside the game(even on the fly). Therefore 'Joe Bloggs' with a 'cheap' stick is at a potential disadvantage. Personally the reduced range of control of sensitivity in CoD compared to IL2 is already quite good at preventing sticks being used in a totally non historic way.
Spiking pots would be a bigger problem

#2, calculate the difference from the different steering columns to a average joystick and use this values for all.
Umm... so someone who spent ~£1700 for a simcontrol spitfire column won't be able to 'tighten' his response to get the new realistic behaviour- or will l'ong stick' users be accused of cheatibg?

#3 opens up a whole can of worms, so I agree, leave it as is

#4, buffet can be simulated with head shake and g with increasing tunnel vision.
good sound cues here also.

#5 A full medical:-P- nah- there'd be hardly anyone left

because it is easy to come up with problems, less so with solutions.

Very much so, but is also often easier to come up with solutions that are worse than the problem;)

Also, why in this entire thread has no real mention been made of the other two axes?

[Al Schlageter]

See my previous post, then. If they're not going to fix it, why have you and your cronies been fighting so hard against it?

Why are you, and your cronies, trying so hard in having it implemented?

It certainly not a bug.

[ACE-OF-ACES]

If it's just a limitation of PC hardware, why have you and your cronies been fighting this issue tooth and nail for 70 pages?
If the developers will never implement it, why have you and your cronies been fighting this issue tooth and nail for 70 pages?
If there are more important things to fix, why have you and your cronies been fighting this issue tooth and nail for 70 pages?
Ah, I see where you are confused..

Allow me..

You are confusing me saying this is not a bug with me saying this did not happen in the real world

Two very different things!

All I am pointing out is there are limits to what a $1,000 PC can do!

For example.. As your pulling 4g's in the simulation, your not physically feeling the effects of 4g's while sitting in front of your computer screen

You not feeling the effects of 4g's is NOT a bug but a limitation of what the PC can do (simulate)

Hope this helps! S!

The vicious lashing out against this issue and people who support realism in this regard has been eye-opening to say the least.
No more eye opening than when the 109 pilots viciously lash out at the mention of the elevator being stuck in cement comes up!

[Glider]

Those 130 accidents also don't include those losses, where after a few insignificant machine gun hits, or even only tracers around the cockpit, the pilot overreacted and went in with his ride because of over-g or a spin, which shurely has happened a few times.

It shurely then was accounted under losses because of enemy action.

There were quite a lot Spitfires lost during the BoB and not all had been shot to pieces.

And glider, nobody has said anything about the Spitfire being weak!!!

Only that the Spitfire controls made it relatively easy to reach the structural limits.

It is a simple fact that if it was relatively easy to reach the structural limit then the limit would have been reached and a lot more would have broken up.

I am sorry but all the evidence is that they didn't. Despite being flown in combat often by inexperienced pilots in the most testing situations, they didn't break up.

When the limit was reached at the end of the war the wings tended to bend not break.

You build into the game a factor that makes it easy for the Spitfire to break up it will be a huge error.

40ish falures in combat, in thousands of aircraft, over the entire war in millions of flights isn't the sign of an aircraft that is easy to break structurally

The comment about some lightly damaged aircraft crashing because an inexperienced pilot over reacted is misleading because it obviously must have happened, but the same logic applies to any fighter in any airforce. Even here, its worth remembering that the Spitfire was easier to fly than the Me109 so logic would say that it was less likely to happen to a Spitfire.

[41Sqn_Banks]

So basically what should be implement is:
- Structural g limit for all aircraft
- Light elevator at high speed for Spitfire

Now let's figure out if both features are already implement and if not submit a feature request.

[ACE-OF-ACES]

So basically what should be implement is:
- Structural g limit for all aircraft
- Light elevator at high speed for Spitfire

Now let's figure out if both features are already implement and if not submit a feature request.
Agreed 100%

[Glider]

Of course Glider, but I wanted you to focus on the bolded part. :-)

That "reported to us" is what gives me doubt about the numbers of total accidents.

It should be really interesting to read those reports: we ignore the investigation's method of the AABI and of course if, as you say, the known accidents were investigated again.

The question is why did you want to focus on the bolded parts. Its always, always the entire picture that counts.

I hope at least that we have dealt with the comments about the Spit wings that bent and needed repair.

[robtek]

So basically what should be implement is:
- Structural g limit for all aircraft
- Light elevator at high speed for Spitfire

Now let's figure out if both features are already implement and if not submit a feature request.

Agreed, but the elevator was not only light but also sensible. (short travel-large reaction)

[ACE-OF-ACES]

There is a point where we all have to realise this it not real..

There are so many things we simmers don't have access to that real pilots had access to

Such that it would be silly to expect us to deal with every aspects of 'reality' in a 'simulation'

On the flip side, we never have to worry about a .50 cal hitting us in the neck while flying

So many things are done in software to make up for this fact.. But I would not refer to them as a bug (make up for the fact it aint real)

Take buffets for example..

In reality in some cases you would probally 'feel' it..

A buzz in your pants or the stick before you 'see' it in real life..

But since the sim can not simulate this (minus those with FFBJS)

The software inserts a screen shake and/or sound to cue the sim pilot into the fact that he is near a stall

At the same time there are so many things (like this topic) that can not be done in software.. But I woudl not refer to them as bugs either (limitations)

In short

No flight simulation ever WAS, IS, or WILL BE REAL!

[Crumpp]

buffet can be simulated with head shake and g with increasing tunnel vision.

To simulate the buffet realistically, the aircraft turn performance should be reduced if one tries to fly in it.

It takes more power to fly in the buffet than it does in smooth air.

The harder an aircraft buffets and more stall warning it delivers, the more power it takes to produce the buffet.

This is exactly why you see aircraft with little to no stall warning and the advent of artificial stall warning devices like stick shakers. With the advent of stick shakers, designers are freed from providing aerodynamic stall warning and can maximize aerodynamic performance.

[bongodriver]

Agreed, but the elevator was not only light but also sensible. (short travel-large reaction)

Not at all speeds though, only at very high speed and only documented on a Spitfire Va on one NACA test.

[Crumpp]

Please note that this happens with a full bomb load (1,000 lb) and the extra rear internal fuel tank. Obviously neither of these were around until late 1944

Right and has nothing to do with piles of bent wings at the repair depots during the Battle of Britain.

[bongodriver]

Right and has nothing to do with piles of bent wings at the repair depots during the Battle of Britain.

That are purely anecdotal

[Crumpp]

must be 'Joe Average' for all pilots,

The NACA did a study as part of the stability and control standards on the forces an average pilot can exert.

I am sure that data could easily build an "average joe" pilot.

It would be easy to implement a fatigue model as well.

It is very interesting, btw.

The current FAR's are based in this same research. The formula for minimum stick force per G required in a stick control column aircraft is:



(Weight of Aircraft / 140lbs) / (structural damage limit - 1)

So a 6500lbs aircraft using a stick as the control input and is fully aerobatic at a structural damage limit of 6G:

(6500lbs/140) / 5 = 9.28Lbs per G minimum required.

[ACE-OF-ACES]

Right and has nothing to do with piles of bent wings at the repair depots during the Battle of Britain.
You saw/have a picture of piles of bent wings?

That would make a cool sig picture!

Not to mention how it would do alot to make your case for this argument!

With that said could you provide me a link to that proof/picture?

Thanks in advance!

If not, and this was just a undocumented statment of yours, no worries, Ill understand the lack of a link provided

[Glider]

Right and has nothing to do with piles of bent wings at the repair depots during the Battle of Britain.

There were no piles of bent wings around repair yards in the BOB. The wings only had a problem in late 1944, when being used in situations far beyond those that could have been thought of pre war.

I produced two lots of evidence, one an original document from the NA which is clear on the issue and the solution, the other points you to the C Shores books on the 2 TAF. Both these support my statement and its only fair to ask you to supply evidence to support yours.

With no evidence your statement is worthless.

PS I do owe you an apology.
You said that the design of the Spitfire wing was done at a number of colleges and I asked you which to which you gave me a number. It was a trick question which you fell for.
You may or may not know what is taught at the establishments you named, but you would not know what they use in their lectures unless you had done the course so your list must have been made up.
Also you said Cambridge as one of the establishments. Cambridge isn't a place where you study. Cambridge is in effect an admin centre for 31 Colleges or to be more precise seats of learning and none of them do aerodynamics.

I can tell you that Cranfield is the premier University for Aerospace in the UK its very advanced with their own test fleet of aircraft. We had visiting lecturers from Cranfield come to HMS Daedalus for some of our studies which included Hovercraft

[IvanK]

To simulate the buffet realistically, the aircraft turn performance should be reduced if one tries to fly in it.

It takes more power to fly in the buffet than it does in smooth air.

The harder an aircraft buffets and more stall warning it delivers, the more power it takes to produce the buffet.

This is exactly why you see aircraft with little to no stall warning and the advent of artificial stall warning devices like stick shakers. With the advent of stick shakers, designers are freed from providing aerodynamic stall warning and can maximize aerodynamic performance.

We have been here before ! As has been stated before Buffet has depth. The very first onset is referred to as the the "Buzz" or the "Tickle" The current RAAF PC-9 Flight manual uses the term "Light Pre Stall Buffet". It is a standard technique (and was in WWII as stated by Geoffery Wellum in his book First light) when trying to get the best out of the aeroplane to smoothly pull to then hold on the "buzz". This is a STANDARD technique taught in most air forces even to this day. Whole training sequences in Military pilots courses are devoted to max performance turning. It is also a standard technique used by Glider pilots trying to get the best out of their machines as well in the thermal centering etc.

Stick Shakers are a relatively new device and have little to do with WWII era aviation. Stick shakers were designed to provide Stall warning as a primary goal not as a device to enable max performance turning..... AOA indicators do a better job in this department. Trying to fly an aeroplane on the shaker (like in a wind shear or GPWS event) is not an easy task as you are in and out of the shaker all the time. In general Stick Shakers are the preserve of the larger transport types from say the DASH 8, B757,B767 with conventional non FBW flight controls. Though some predominately Russian fighter types with conventional flight controls (early MIG29) do have similar devices (including pedal shakers) to provide Max AOA cueing.

We all know flying in deep buffet requires more power. I think you will find Energy bleed in CLOD is increased quite significantly IN the buffet.

Flying on the buzz is a valid technique to get the best turn performance out of the aeroplane.

I posed a situation before when this was the subject of another of these Mammoth "intellectual" threads... the answer was avoided. Picture this situation.

You find yourself in your Spitfire MKI 90 degrees nose down at very low altitude. You are not sure if you have the turning room to avoid the ground.
Your only chance is to get the absolute minimum radius turn RFN... how are YOU going to fly the turn .. no time to think ... delay compounds the issue.... FAILURE = DEATH.

[NZtyphoon]

The NACA did a study as part of the stability and control standards on the forces an average pilot can exert.

I am sure that data could easily build an "average joe" pilot.

It would be easy to implement a fatigue model as well.

It is very interesting, btw.

The current FAR's are based in this same research. The formula for minimum stick force per G required in a stick control column aircraft is:



(Weight of Aircraft / 140lbs) / (structural damage limit - 1)

So a 6500lbs aircraft using a stick as the control input and is fully aerobatic at a structural damage limit of 6G:

(6500lbs/140) / 5 = 9.28Lbs per G minimum required.

Please explain how this translates to a computer sim, and how will the developers adapt this formula to cater for the different types of joysticks/rudder pedals used by members of the IL2 community?

[Crumpp]

PS I do owe you an apology.
You said that the design of the Spitfire wing was done at a number of colleges and I asked you which to which you gave me a number. It was a trick question which you fell for.
You may or may not know what is taught at the establishments you named, but you would not know what they use in their lectures unless you had done the course so your list must have been made up.
Also you said Cambridge as one of the establishments. Cambridge isn't a place where you study. Cambridge is in effect an admin centre for 31 Colleges or to be more precise seats of learning and none of them do aerodynamics.

I can tell you that Cranfield is the premier University for Aerospace in the UK its very advanced with their own test fleet of aircraft. We had visiting lecturers from Cranfield come to HMS Daedalus for some of our studies which included Hovercraft


Which has what to do with anything?

I never claimed to go to Cambridge. I went to Embry Riddle. I do have friends who went to other colleges and they also know of the Spitfire's instability.

What does your point have to do with that fact or any fact relevant to this discussion?

Or the fact, it is Cambridge University that published the book??

Cambridge University, Engineering Department, Trumpington Street, Cambridge CB2 1PZ, UK
Tel: +44 1223 332600, Fax: +44 1223 332662

Before coming to Cambridge in October, you must complete this booklet of problems, produced by the Department. It contains questions on mathematics, geometry, mechanics, DC electrical circuits and electromagnetism, to help prepare you for lectures. There is a supporting Website containing guidance notes and links to learning resources (as well as
the booklet itself in PDF format). Your college will send you a username and password to access the material online, and will either send you a hard copy of the booklet, or direct you to print your own copy from the Website. Your
Director of Studies will give you further guidance on tackling these problems, and may ask for the work to be handed in at the start of your first term, for discussion in your first supervisions.

http://www.eng.cam.ac.uk/teaching/index-freshers.html

http://maps.google.com/maps?q=Cambridge+University,+Engineering+Departmen t,+Trumpington+Street,+Cambridge&hl=en&sll=35.191767,-79.859619&sspn=7.67316,16.907959&hq=Cambridge+University,+Engineering+Department,&hnear=Trumpington+St,+Cambridge,+United+Kingdom&t=m&z=16&iwloc=B

[Crumpp]

The very first onset is referred to as the the "Buzz" or the "Tickle"

Right, which has what to do with the fact some airplanes have higher energy stall warning's including buzz than others?

Also, what does that have to do with the ability of a pilot to precisely fly to the nibble and precisely back off to smooth air in order to maximize his aircraft's turn performance?

[IvanK]

Are you going to have a go at answering the the dive recovery question ?

[ACE-OF-ACES]

Hey guys

Based on your experances with Crump..

Is it safe for me to assume that since he has NOT produce a picture of..

How did he say it?

piles of bent wings at the repair depots during the Battle of Britain

That he was just talking out of his 'A' and that I should stop waiting for him to provide the link to said picture..

Thanks in advance!

[Crumpp]

Are you going to have a go at answering the the dive recovery question ?

I would not want to be in this situation with an aircraft that is neutral or unstable as you want to be able to pull precisely and quickly to the maximum acceleration the airframe can handle while reducing power.

We have had this discussion before on the "nibble", too. If you are in the nibble, you are NOT flying a maximum performance constant altitude turn.

What does that have to do with the ability of a pilot to precisely fly to the nibble and precisely back off to smooth air in order to maximize his aircraft's turn performance?

[Crumpp]

IvanK,

Your question really makes one wonder how many of those men did not return home because their airframe failed.

If you read Morgan and Shacklady, there is a listing of each serial number and its fate. There are early Mark Spitfires that were lost to "structural failure" or "wing came off in aerobatic flight".

[Crumpp]

IvanK,

Your question really makes one wonder how many of those men did not return home because their airframe failed.

If you read Morgan and Shacklady, there is a listing of each serial number and its fate. There are early Mark Spitfires that were lost to "structural failure" or "wing came off in aerobatic flight".

Most of the listing were just lost to unknown circumstances.

[DC338]

T-38 manual

"Begin by entering a 2 to 3 G turn with MIL power and approximately 300 KCAS. Increase the bank and backstick pressure as required to achieve the light buffet in a level turn. Note the turn rate.This is optimum turn performance for the T-38."


T-45 ACM manual:

"In general, if you don't know what to do, nibble of
buffet is a good place to start to maneuver your airplane well"

"Our break turns should be the nibble of buffet AT A MINIMUM, more like heavy buffet."

[Crumpp]

T-38 and T-45 are both jets...thrust limited and both have low aspect ratio wings.

Follow the Spitfire Operating Notes for a high aspect ratio aircraft that is aerodyanmically limited:

http://img607.imageshack.us/img607/2471/page15j.jpg (http://imageshack.us/photo/my-images/607/page15j.jpg/)

[IvanK]

I would not want to be in this situation with an aircraft that is neutral or unstable as you want to be able to pull precisely and quickly to the maximum acceleration the airframe can handle while reducing power.

We have had this discussion before on the "nibble", too. If you are in the nibble, you are NOT flying a maximum performance constant altitude turn.

What does that have to do with the ability of a pilot to precisely fly to the nibble and precisely back off to smooth air in order to maximize his aircraft's turn performance?

Its not a case of not "wanting" to be in the situation... Operational pilots often find themselves in situations they dont want to be in. The question put was quite specific, a Spitfire MKI no AOA gauges no accelerometers just you the pilot and your basic airframe.

How do you propose to "back off from the nibble" and by exactly how much? especially in an aeroplane with such lack of precision in the pitch circuit as you imply throughout this thread ? Your life is hanging in the balance, what cue do you have in your Spit MKI that you are doing your best ?

I think all thats going to happen with your technique is the "crump" sound as the Spitfire MKI impacts Terra firma. If you think you can back off the buzz/tickle/nibble and guarantee where you really are you are dreaming ! .... thats why buzz/tickle/nibble feel is taught to Miltary pilots world wide.

[Sandstone]

Right and has nothing to do with piles of bent wings at the repair depots during the Battle of Britain.

Crumpp, I've never heard of piles of bent wings during the BoB as a result of either pitch sensitivity or instability. It sounds quite extraordinary. Can you supply some references?

[IvanK]

From "Aerobatics Principles and Practice" by David Robson, ex Fighter Pilot,Miltary test pilot (ETPS graduate.)

http://i40.photobucket.com/albums/e215/zulu64/buffetaeros.jpg

[Glider]

Which has what to do with anything?

I never claimed to go to Cambridge. I went to Embry Riddle. I do have friends who went to other colleges and they also know of the Spitfire's instability.
I know that you didn't go to Cambridge as to Embury Riddie that may or may not be the case. I do know that when you offerred to debate Longitudional Stability by standards one was to do with roll rates and nothing to do with what you wanted. I believe that one of the other standards you wanted to use is to do with ordering spare parts, not exactly stability. I wouldn't expect a graduate from Embry Riddle to make that kind of mistake, its possible of course but it is a basic error

But you did say that Cambridge and others used the Spitfire wing when you clearly don't know


What does your point have to do with that fact or any fact relevant to this discussion?
Because its another example of you making up statements without foundation to support your case.



Or the fact, it is Cambridge University that published the book??
Cambridge University Press is a publishing house NOT a University. The University is an admin for the collages not a seat of learning and supplies support to the member seats of learning, including publishing.


http://www.eng.cam.ac.uk/teaching/index-freshers.html

http://maps.google.com/maps?q=Cambridge+University,+Engineering+Departmen t,+Trumpington+Street,+Cambridge&hl=en&sll=35.191767,-79.859619&sspn=7.67316,16.907959&hq=Cambridge+University,+Engineering+Department,&hnear=Trumpington+St,+Cambridge,+United+Kingdom&t=m&z=16&iwloc=B

These tend to prove that you trawled for something to support your statement rather than have actual evidence

Speaking of evidence and more importantly, we are all waiting for your source or evidence re piles of bent wings in the BOB waiting for repair. I produced two pieces of evidence you have have yet to produce anything.

You once accused me of being unprofessional so either substantiate your claim or withdraw it, its the professional thing to do

[Crumpp]

From "Aerobatics Principles and Practice" by David Robson, ex Fighter Pilot,Miltary test pilot (ETPS graduate.)


Right....

Edge of the Buffet is not IN the buffet.

http://img835.imageshack.us/img835/1654/buffetaeros.jpg (http://imageshack.us/photo/my-images/835/buffetaeros.jpg/)


If you have no other guide, the buzz is useful for finding CLmax. Don't fly in the nibble but back off to just before though IF you want maximum turn performance.

Lift varies with angle of attack and airspeed. The highest useful angle of attack is just before the critical angle, about 15 degrees. At this high angle of attack, maximum CL, considerable drag is produced, and if the aeroplane stalls, or the buffet is reached, the drag will increase dramatically. Ideally, sufficient backpressure should be applied to activate the stall warning (if it is operating) on its first note. Alternatively, the very edge of the buffet will need to be used as a guide to maximum CL.


http://www.caa.govt.nz/FIG/advanced-manoeuvres/maximum-rate-turns.html

You can fly in the nibble if you want, IvanK. However somebody that is turning in the same airplane at the point of smooth air just before the nibble will out turn you. That is how the physics works.

Its not a case of not "wanting" to be in the situation... Operational pilots often find themselves in situations they dont want to be in. The question put was quite specific, a Spitfire MKI no AOA gauges no accelerometers just you the pilot and your basic airframe.


Right.....Again, I would not want to be in that situation with a neutral or unstable aircraft with a light stick force per G and extremely small amount of available stick control.

That why we see charge sheets with "structural failure" and "wings came off in aerobatic flight".

But you did say that Cambridge and others used the Spitfire wing when you clearly don't know
Quote:


Making up what????

Start another thread on this off topic sideshow. Cambridge awards degrees, they published the book, and it is used as a reference in many engineering curriculuums.

If you don't like those facts, tell Cambridge not me.

[NZtyphoon]

IvanK,

Your question really makes one wonder how many of those men did not return home because their airframe failed.

If you read Morgan and Shacklady, there is a listing of each serial number and its fate. There are early Mark Spitfires that were lost to "structural failure" or "wing came off in aerobatic flight".

Most of the listing were just lost to unknown circumstances.

Of course you are going to provide a listing of all Mk Is - with evidence -lost to structural and wing failure between 1939 and the middle of 1941 because after that most Mk Is ended up at OTUs.

Then you can list all Mk IIs lost to same cause - with evidence.

Then list all Mk Vs, knowing that from Quill several Spitfire Vs were lost due to bad loading at a squadron level in 1942.

As for "lost to unknown causes" this could mean anything and to use this category to prove anything is a waste of time

In fact how about we all do a search for early Spitfires lost to wing or structural failure?

From http://www.spitfires.ukf.net/ which is well researched and more accessible than M & S

Mk I

K - N series (first two production batches Spitfire I)

*K9838 Ia 51 EA MII FF 6-1-39 41S 11-1-39 struct fail in dive Eryholme Yorks 16-3-39 SOC FH21.25 pilot killed

K9977 Ia 191 EA MII FF 16-5-39 602S 18-5-39 lost wing during aerobatics crashed Haddington CE Lothian 30-12-39 Sgt Bailey killed SOC 11-2-40

N3120 Ia 391 EA MIII FF 29-10-39 6MU 3-11-39 266S 20-1-40 broke up in test flight to alt Pilot Gleed thrown out crashed 14.40hrs Littleport Cambs 18-2-40 SOC 22-2-40

*#N3191 Ia 432 EA MIII FF 23-11-39 24MU 2-12-39 234S 22-3-40 lost wings in dive crashed nr Truro Cornwall CE 16-1-41 AST 14-2-41 SOC 23-4-41

Four

R Series:

R6692 Ia 746 EA MIII FF 3-6-40 6MU 5-6-40 609S 7-6-40 Overstressed attacking Ju88 CE 12-8-40 SOC 2-9-40

#R6777 Ia 803 EA MIII FF 21-6-40 8MU 22-6-40 65S 12-7-40 C2 ops 30-7-40 GAL 616S 20-8-40 72S 2-9-40 92S 3-11-40 145S 4-2-41 AFDU 6-3-41 152S 13-3-41 SF H 10-4-41 57OTU 4-8-41 61OTU 3-1-42 Broke up in air and crashed Blackbill Glam FAC3 8-7-42

#R6882 Ia 840 EA MIII FF 1-7-40 (CMG) 6MU Brize Norton 28-7-40 cannon wing fitt 7OTU 3-9-40 AFDU Duxford 11-1-41 R-RH 10-2-41 Cv Vb M45 92S 'QJ-N' 9-3-41 609S 30-8-41 Broke up in air and abandoned 2.5m NE of East Stoke Notts FACE 10-1-42 SOC 17-1-42

$R7033 PRIV 1738 HEA M45 HAL 8-6-41 Cv PRIII Type C 1PRU Benson 7-8-41 loss of control in storm at high alt pilot thrown clear at 1000ft landed safe total wreck nr Bishops Stortford 5-10-41 remains to RAE for accident invest 1-42

#R7064 Ia 1431 EA MIII FF 5-2-41 9MU 6-2-41 411S 5-7-41 52OTU 23-11-41 struct damaged in spin crashed and hit fence nr Aston Down CE 25-3-42 SOC 3-4-42

Five

X4009 - X4997

*X4056 Ia 972 EA MIII FF 1-8-40 39MU 2-8-40 616S 30-8-40 Wing came off during dive 8m SE of Kirton-in-Lindsey FAC3 8-11-40 SOC 11-11-40

#X4234 Ia 1031 EA MIII FF 15-8-40 8MU 16-8-40 609S 24-8-40 damaged combat P/O Staples safe 27-9-40 AST 66S 13-10-40 57OTU 1-11-40 FACB 27-6-42 ros wing fail in spin crashed Alsager Cheshire CE 25-9-42

X4613 Ia 1233 EA MIII FF 15-10-40 6MU 15-10-40 ? 603S 17-10-40 266S 24-10-40 Lost wing and crashed Gedney Hill Lincs CE 2-3-41 SOC 20-3-41

*X4662 Ia 1260 EA MIII FF 1-11-40 9MU 8-11-40 485S 15-3-41 61OTU 25-6-41 131S 17-7-41 pull out steep dive stbd wing broke away crashed dbf pilot killed 12.07hrs Northallerton 27-7-41 SOC 1-8-41

*X4680 Ia 1264 EA MIII FF 2-11-40 12MU 5-11-40 72S 17-1-41 CB ops 9-4-41 Scottish Aviation 123S 3-6-41 steep dive and pull out from cloud wings and tailplane broke off fus hit ground Kirknewton pilot killed 16.00hrs 15-6-41 SOC 1-7-41 FH77.50 RAE accident invest 20-8-41

#X4854 Ia 1351 EA MIII FF 14-12-40 MU 16-12-42 53OTU into sea nr Dunraven Castle Thought struct fail of stbd wing 2-1-43

*X4381 Ia 1122 EA MIII FF 6-9-40 6MU 10-9-40 152S 13-9-40 501S 'SD-J' 5-11-40 53OTU 7-7-41 stbd wing broke off after high speed dive out of cloud Tonpentre nr Pontypridd dbf CE 16.30hrs 6-8-41 SOC 21-8-41 RAE 30-1-42

*X4421 Ia 1138 EA MIII FF 12-9-40 8MU 13-9-40 66S 16-9-40 57OTU 21-10-40 steep dive from low cloud violent pull out high speed stall spun wing fail Pilot thrown clear but killed 15.15hrs crashed Northrop Flints 27-3-41 SOC cancel RAE 8-4-41 AST 13-5-41 rebuilt as Va M45 164S 29-4-42 FACE 18-8-42 (Rebuild suspect)

Eight

17 with structural or wing failure, seven (*) of which occurred during a dive or pulling out of a dive: See Henshaw

http://i91.photobucket.com/albums/k304/Major_Sharpe/Henshaw12-page-003a.jpg
http://i91.photobucket.com/albums/k304/Major_Sharpe/Henshaw13-page-001a.jpg

Of the rest (#) six - N3191, R6777, R6882, R7064, X4234, X4854 - were old, retired Spitfire Is in OTUs. One, R7033, was a PRU aircraft caught in a storm at high altitude.

Out of 17 structural failures three were recently delivered Spitfires: two, K9977 and N3120 had structural or wing failures before the Pilot's Notes were printed in July 1940 while K9838 broke up in a dive in early 1939 - it might well have been these three incidents which prompted the warnings to be printed.

[Crumpp]

either substantiate your claim or withdraw it

Why don't your read Morgan and Shacklady. They have a list of the serial numbers and known fates of many of the Spitfires.

They even have pictures of the remains of some of the aircraft that shed wings during high speed maneuvering.

Are you going to make me scan them or can you just pick up the book and read it?

[6S.Manu]

The question is why did you want to focus on the bolded parts. Its always, always the entire picture that counts.

Infact it's the entire picture... they says those were the accidents reported to them... it's only a speculation that they were the only accidents during all the war as you said since:

1) Was the AAIB the only one actually called to investigate on accidents?
2) How many accidents were not reported?
3) We don't know the AAIB method of investigation: did they need the wreckage?... or they could investigate by interviews with the witnesses of the accident?
4) As you says, I repeat, I can be that some accidents not reported as result of a past investigation. A plane is losing its wings during recovery from a dive? The first accident of this kind required an investigation, probably also the second one... but how many until it's clear that the plane can be pull so much and it become ?

We can't have unanswered questions... until then I can't trust they are not the only accidents during the world war.

The one you posted is not a fact, but it's a very good starting point for the real one.

[NZtyphoon]

Why don't your read Morgan and Shacklady. They have a list of the serial numbers and known fates of many of the Spitfires.

They even have pictures of the remains of some of the aircraft that shed wings during high speed maneuvering.

Are you going to make me scan them or can you just pick up the book and read it?

In fact it's much easier going through http://www.spitfires.ukf.net/ which is better researched and better laid out, and more accessible, then M & S.


Infact it's the entire picture... they says those were the accidents reported to them... it's only a speculation that they were the only accidents during all the war as you said since:

1) Was the AAIB the only one actually called to investigate on accidents?
2) How many accidents were not reported?
3) We don't know the AAIB method of investigation: did they need the wreck?... or they could investigate by interviews with the witnesses of the accident?
4) As you says, I repeat, I can be that some accidents not reported as result of a past investigation. A plane is losing its wings during recovery from a dive? The first accident of this kind required an investigation, probably also the second one... but how many until it's clear that the plane can be pull so much and it become ?


1) The body responsible for investigating air accidents before and during WW2 was the AIB (Accidents Investigation Branch) which was responsible for investigating all air accidents. http://www.aaib.gov.uk/about_us/history.cfm
2) Why bother speculating on a question which can never be answered? It's like asking how long is a piece of string.
3) Presumably whatever was available - if a wreck was at the bottom of the sea AIB would not have gone chasing after it.
4)Again, unquantifiable speculation

[Crumpp]

See Henshaw


Good stuff...

He says 25 were lost due to structural failure he uncovered in his research. That is quite a few.

That is only the ones that were lost due to total failure as well as the ones we know about. It does not tell us the number of aircraft which flew home with bent wings or the ones that broke up over enemy territory.

To put that 25 unfortunate Spitfires in perspective:

~2488 Spitfire Mk I and II's were produced

2488/25 = 99.52

So for every 100 Spitfires, one was lost to structural failure.

Now let's compare that to the Beechcraft Bonanza which also had some developmental issues with the V-tail that resulted in structural failure. It is the airplane that forged the "Doctor Killer" reputation.

>17000 Beechcraft Debonair/Bonanza's have been built.

Taking structural failures from 2007 on back we find that 148 airframes have been lost. We have much better records of a peacetime GA aircraft.

http://www.thomaspturner.net/inflight%20breakups%20NTSB.htm

17,000 / 148 = 114.8

So, For every 115 Beechcraft Debonair/Bonanza's built, ONE has experienced structural failure.

http://www.tsgc.utexas.edu/archive/general/ethics/vtail.html

I think the early Mark Spitfire would have had the same reputation in peacetime as the Bonanza due to its high rate of structural failure.

The events of WWII overshadowed the longitudinal instability issue in the early Mark Spitfires.

[bongodriver]

1) Was the AAIB the only one actually called to investigate on accidents?
2) How many accidents were not reported?
3) We don't know the AAIB method of investigation: did they need the wreckage?... or they could investigate by interviews with the witnesses of the accident?
4) As you says, I repeat, I can be that some accidents not reported as result of a past investigation. A plane is losing its wings during recovery from a dive? The first accident of this kind required an investigation, probably also the second one... but how many until it's clear that the plane can be pull so much and it become ?



1) in all probability yes....it's their job, why call in people who aren't qualified?
2) probably a very small amount, in all likelyhood just the events which lead to MIA and unknown fates.
3) as long as the methods produced the answer does it matter?
4) let's not forget that most Spitfire pilots were flying with a squadron and the squadron pilots are all credible eye witnesses to what happens, through all of the recounted stories and biographies etc nobody ever mentioned the Spitfire as being 'particularily' weak or seeing squad mates breaking up with any regularity.

[Crumpp]

4) As you says, I repeat, I can be that some accidents not reported as result of a past investigation. A plane is losing its wings during recovery from a dive? The first accident of this kind required an investigation, probably also the second one... but how many until it's clear that the plane can be pull so much and it become ?

#4 Again, unquantifiable speculation

It is not speculation. It is a fact, the early mark Spitfire had neutral to unstable longitudinal stability at normal and aft CG. It is a fact, the controls were too light and too effective.

This combination is why you see the warnings in the Operating Notes.

It was real and it could kill you if ignored.

[IvanK]

So now we have Beechcraft Bonanzas and Debonairs in this Spitfire thread !!!!!! .... talk about thread drift.

Keeping with the drift though, in your Bonanza V tail structural failure number crunching example you quote 17,000 Bonanza/Debonairs being made but isnt the Debonair a single fin aeroplane ? Did it have the same structural issues as the V tail Bonanzas ? If it did fair enough but if it didn't should it be included ?

Dont really care either way just saying.

[Glider]

. Cambridge awards degrees, they published the book, and it is used as a reference in many engineering curriculuums.

If you don't like those facts, tell Cambridge not me.

Cambridge don't issue degrees, they do publish books which are used in institutions but they do not teach.

However and most importantly we are still waiting for your evidence to support your statement about piles of bent wings in the BOB.

Without evidence your statement is useless, should be withdrawn and without it your argument goes with it.

You will agree I am sure that it the professional approach

[Glider]

Once again you are putting your own spin onto a paper that it presented to you.

Good stuff...

He says 25 were lost due to structural failure he uncovered in his research. That is quite a few.

That is only the ones that were lost due to total failure as well as the ones we know about. It does not tell us the number of aircraft which flew home with bent wings or the ones that broke up over enemy territory.

To put that 25 unfortunate Spitfires in perspective:

~2488 Spitfire Mk I and II's were produced

2488/25 = 99.52

Where does he say only Mk 1 and II's? He doesn't so lets apply your logic to all the spits produced in the war
23,000/25 = 920
So for every 100 Spitfires, one was lost to structural failure.
So for every 920 Spitfires one was lost to structural failure

Now let's compare that to the Beechcraft Bonanza which also had some developmental issues with the V-tail that resulted in structural failure. It is the airplane that forged the "Doctor Killer" reputation.

>17000 Beechcraft Debonair/Bonanza's have been built.

Taking structural failures from 2007 on back we find that 148 airframes have been lost. We have much better records of a peacetime GA aircraft.

http://www.thomaspturner.net/inflight%20breakups%20NTSB.htm

17,000 / 148 = 114.8

So, For every 115 Beechcraft Debonair/Bonanza's built, ONE has experienced structural failure.
So for every 920 Spitfires produced in the war ( I could increase this number to all spits built) One experienced a structural failure.
In other words you are about 8 times safer in a Spit in wartime than in a peacetime Bonanza
I think the early Mark Spitfire would have had the same reputation in peacetime as the Bonanza due to its high rate of structural failure.

I think the early Mark Spitfire would have had a much better reputation in peacetime than the Bonanza due to its much safer record iro structural security

[6S.Manu]

Thks for the answers.


1) The body responsible for investigating air accidents before and during WW2 was the AIB (Accidents Investigation Branch) which was responsible for investigating all air accidents. http://www.aaib.gov.uk/about_us/history.cfm
2) Why bother speculating on a question which can never be answered? It's like asking how long is a piece of string.
3) Presumably whatever was available - if a wreck was at the bottom of the sea AIB would not have gone chasing after it.
4)Again, unquantifiable speculation

1) in all probability yes....it's their job, why call in people who aren't qualified?
2) probably a very small amount, in all likelyhood just the events which lead to MIA and unknown fates.
3) as long as the methods produced the answer does it matter?
4) let's not forget that most Spitfire pilots were flying with a squadron and the squadron pilots are all credible eye witnesses to what happens, through all of the recounted stories and biographies etc nobody ever mentioned the Spitfire as being 'particularily' weak or seeing squad mates breaking up with any regularity.

1) I looked in the website but I asked because it's not written that's the only responsable of investigation but it's part of the entire Department.

A Department could delegate some accidents to a company and other crashes to another: my doubt is the existence of another qualified company during that time... it's a natural to make use of external help (the AAIB was indipendent) during difficult times. So is it sure that the RAF had not a internal investigation departement and AAIB was the only responsable? Could it be that it was responsable for the accidents in a determined territory (England)?

2) & 3) I ask because of the possibility of not investigated accidents regarding structural failure: if so the Mr.Newton's numbers posted by Glider are far less interesting: as I said, since those were only accidents with a defined wreckage, how many more planes went down for structural failure over the sea (the channel, Malta ect)?
I think an investigation would always require witnesses... my question was if there would be an investigation at all in case of no wreckage.

4) Bongo, I know... infact I expect that the loss of the wings was a rare accident: I think more of a not critically damaged airframe for which, I think to have read somewhere, the plane had to be partially rebuild... could a plane with partial airframe damage have the same performance? Does its manouvrability and stability remain the same? Because IMO in combat area easily a damaged plane would be taken down by the enemy...

I know it's speculation, but not useless IMO. To have the complete picture we need to be sure of these things, otherwise there is no absolute truth. ;)

[NZtyphoon]

Good stuff...

He says 25 were lost due to structural failure he uncovered in his research. That is quite a few.

That is only the ones that were lost due to total failure as well as the ones we know about. It does not tell us the number of aircraft which flew home with bent wings or the ones that broke up over enemy territory.

To put that 25 unfortunate Spitfires in perspective:

~2488 Spitfire Mk I and II's were produced

2488/25 = 99.52

So for every 100 Spitfires, one was lost to structural failure.

Garbage, he's talking about all Spitfires built

http://i91.photobucket.com/albums/k304/Major_Sharpe/Henshaw12-page-003b.jpg

~20,351/25 Spitfires built = 1 in 821


>17000 Beechcraft Debonair/Bonanza's have been built.

Taking structural failures from 2007 on back we find that 148 airframes have been lost. We have much better records of a peacetime GA aircraft.

http://www.thomaspturner.net/inflight%20breakups%20NTSB.htm

17,000 / 148 = 114.8

So, For every 115 Beechcraft Debonair/Bonanza's built, ONE has experienced structural failure.

http://www.tsgc.utexas.edu/archive/general/ethics/vtail.html

I think the early Mark Spitfire would have had the same reputation in peacetime as the Bonanza due to its high rate of structural failure.

Nope, the Beechcraft, a high speed interceptor fighter built to withstand combat conditions in wartime, was 7 - 8 times more likely to fall apart. :grin: :grin: :grin:


He says 25 were lost due to structural failure he uncovered in his research. That is quite a few.

That is only the ones that were lost due to total failure as well as the ones we know about. It does not tell us the number of aircraft which flew home with bent wings or the ones that broke up over enemy territory.


One can speculate on this as much as one likes - unless Crumpp or anyone else can provide documentary evidence to back such statements that's all it is. Besides which Spitfires returning home, even with buckled wings (assuming the stacks of buckled wings seen in MU hangers can be believed), were not destroyed through structural failure and could be repaired and put back into service.

To match Beechcraft Bonanza stats for every Spitfire known to have been destroyed through structural failure another 4.5, or over 100 at least would have to fail over enemy territory - a wonderful propaganda opportunity had it happened. No doubt Crumpp can present lots of documented evidence that this happened.

So now we have Beechcraft Bonanzas and Debonairs in this Spitfire thread !!!!!! .... talk about thread drift.

Keeping with the drift though, in your Bonanza V tail structural failure number crunching example you quote 17,000 Bonanza/Debonairs being made but isnt the Debonair a single fin aeroplane ? Did it have the same structural issues as the V tail Bonanzas ? If it did fair enough but if it didn't should it be included ?

Dont really care either way just saying.

The V-tail has a very high rate of in-flight failures. Compared with the Model 33, which is the same aircraft with a conventional straight-tail, the V-tail has a fatal in-flight failure rate 24 times as high as the Straight tail Bonanza. In spite of this glaring statistic, Beech claimed that there was no problem with the V-tail, and for many years the public seemed to agree with Beech. However, the deaths from in-flight failures continued to mount. The V-tail Bonanza is a classic tale of a dangerous item, which because of its popularity continued to kill.

Can't remember anything like this being written about the Spitfire, even by its harshest critics, including NACA and the Pilot's Notes...:grin:

[Crumpp]

Because IMO in combat area easily a damaged plane would be taken down by the enemy...


That is correct. A bent airframe is not good. The plane is hard to control and weakenend.


I ask because of the possibility of not investigated accidents regarding structural failure

There were plenty of uninvestigated accidents. In wartime, they would be chaulked up to the enemy. Common sense tells us that wings coming off in a dogfight would be chaulked up to enemy fire or pilot suddenly breaking out of a turn to wings level was hit.

There would be no way to resurect the dead or examine the wreckage to discover the airframe was broken during a flick maneuver or bent in a hard turn above Va.

Facts are we will never be able to quantify that statistic. None of this changes the defined and measured characteristics of the aircraft nor does it invalidate the Operating Note warnings.

Where does he say only Mk 1 and II's?

The issue was solved in the Spitfire Mk V!!

You understand that the bob-weights and subsequent empennage changes to the design were to fix the instability??

It is only a factor in the early Mark Spitfires.

Aerodynamically, the instability is a very easy fix. The only reason it was not solved much earlier is the fact the Air Ministry had no defined standards for stability and control. Without measureable standards, the pilot stories of "easy to fly" simply overshadowed the few engineers who knew better.

[NZtyphoon]

The issue was solved in the Spitfire Mk V!!

You understand that the bob-weights and subsequent empennage changes to the design were to fix the instability??

It is only a factor in the early Mark Spitfires.

Please provide documented evidence that Henshaw was only referring to Spitfire Is and IIs, otherwise this is just clutching at straws.

AA876 Vb 2223 EA M45 FF 25-10-41 during test flight 6-2-42 George Pickering reached a speed of 520mph in a dive. The aircraft disintigrated He was severely injured and never flew again. SOC before delivery not to be replaced. Airframe to RAE 9-4-42 for accident invest

MA480 IX CBAF M63 46MU 1-6-43 82MU 14-6-43 La Pampa 2-7-43 Casablanca 14-7-43 Middle East 1-9-43 Dived into ground Egypt FACB 10-10-43

[Glider]

We do seem to be in the normal situation where one side produces evidence to the best of their ability and often in duplicate. And the nay sayers produce nothing to support theirs and depend on ever more silly questions.

On the Bent wings waiting repair being a 1944 issue
1) An original document from the NA which is clear as to the cause of the problem in late 1944 and how to resolve it
2) the 2TAF series of books from C Shores a highly recognised author on aviation which also says the same

On the Bent wings waiting repair being a BOB issue
1) Someone says that they remember reading something somewhere
2) Crumpps statement with nothing to support it
In other words nothing

On the number of Breakups due to structural faiulure being small
1) A published work written by someone involved in Air Investigations for 50 years
2) The numbers matching those printed in the M S book
3) Henshaws paper the number are different but even lower

On the numbers of breakups being higher
1) I looked in the website but I asked because it's not written that's the only responsable of investigation but it's part of the entire Department.In otherwords the department has more responsibilities and this section is responsible for Air Investigations.
2) Statements that others may have come down at sea or in enemy held areas.
Of course this almost certainly happened. However its a question that we will never know the results to. Its something that happens to every airforce all we can do is do the best we can with what we know. In the same way we do not know how many of these had been damaged in combat.

[Al Schlageter]

So can we take it that Crumpp, given, the chance, would not pilot an early Mk of Spitfire as it was a death trap?

Notice they are all over the sky and even upside down.
http://www.youtube.com/watch?feature=endscreen&NR=1&v=TXxzlOH92as
http://www.youtube.com/watch?v=c6c3v9iihgw&feature=related

[Glider]

That is correct. A bent airframe is not good. The plane is hard to control and weakenend..
True but it gets you home a broken one doesn't

.
The issue was solved in the Spitfire Mk V!!

You understand that the bob-weights and subsequent empennage changes to the design were to fix the instability??

It is only a factor in the early Mark Spitfires..
True but you need to prove that he is only talking about Mk I and II. Its worth remembering that the fix wasn't in place for the start of Mk V production so you need to factor that in.

And you still need to prove that there were any bent wings in the BOB waiting repair let alone the statement you made. Without evidence you have no back up and its only another unsupported theory.

[Glider]

So can we take it that Crumpp, given, the chance, would not pilot an early Mk of Spitfire as it was a death trap?

Notice they are all over the sky and even upside down.
http://www.youtube.com/watch?feature=endscreen&NR=1&v=TXxzlOH92as
http://www.youtube.com/watch?v=c6c3v9iihgw&feature=related

Crumpp you better talk to Duxford they may not know what you know

[Crumpp]

Just going thru the list in Morgan and Shacklady, I have counted 13 structural failures so far and I am only halfway thru the Mark I list.

It was serious enough that X4228 went to Farnborough on 24-8-40 to be used in testing to discover the cause of wing structure failures.

On a side note, X4181 on 17-840 was designated in 616 Squadron for "100 Octane Testing" and was shot down by a Bf-109 on 26-8-40.

Should have read this list earlier!!

[Crumpp]

17,000 Bonanza/Debonairs being made but isnt the Debonair a single fin aeroplane ?

The accident statistics include both types.

Again, the failures were notable enough for the RAF to send the plane to be tested to discover why the wings were failing in August of 1940.

Damn shame they did not have standards in place and that stability and control was such a new science at the time. Lives could have been saved.

[6S.Manu]

We do seem to be in the normal situation where one side produces evidence to the best of their ability and often in duplicate. And the nay sayers produce nothing to support theirs and depend on ever more silly questions.

Curiosity and research for detail are silly questions?... tell me you're not an historian...


On the number of Breakups due to structural faiulure being small
1) A published work written by someone involved in Air Investigations for 50 years
2) The numbers matching those printed in the M S book
3) Henshaws paper the number are different but even lower

And you call this evidence!?!?

What about the M S book having the same source of "Spitfire at war" => AAIB?

Now if the AAIB data is not usefull to understand the real rate of structural damage, since it ignores the accident over the sea and in enemy territory, what is the meaning to post it?
The real numbers are different, period, since we don't know how many poor guys died for overstressed airframe and they were filed as KIA because of the enemy.

3 books: one has different numbers... Which ones are the corrected numbers?

Look I've "produced" a question about that data...


On the numbers of breakups being higher
1) I looked in the website but I asked because it's not written that's the only responsable of investigation but it's part of the entire Department.In otherwords the department has more responsibilities and this section is responsible for Air Investigations.

Really? I ask it because I don't know... I would like a doc by the Air Ministry stating that every accident need to be investigated officialy by the AAIB.

Or if Mr.Newton said "We had to investigate every accident during the war" it would be enough. But it does not say it... so sorry if I've some silly doubt.

2) Statements that others may have come down at sea or in enemy held areas.
Of course this almost certainly happened. However its a question that we will never know the results to. Its something that happens to every airforce all we can do is do the best we can with what we know. In the same way we do not know how many of these had been damaged in combat.
Then that number about the rate of Spitfires lost for airframe damage is almost useless since it's a small sample mostly no related to combat. That was my first statement.

In enemy territory, in combat, numbers can easily be different. Are numbers about accidents because of clouds really important when they did fight at 5km??? Does the pilot need to land in the fog in enemy territory?

So lets stick to the data about stick forces, oversensivity, AoA e structural limits and lets try to analyse them together. Without the necessity to bring on numbers and reports who do not help.

Mainly because THEY DID NOT FLY AS WE DO IN THE SIM.

[Crumpp]

Crumpp you better talk to Duxford they may not know what you know


I sure they know it. Everyone of those Spitfires is modified so that it does not have the instability of the early marks.

Damn shame they did not have standards in place and that stability and control was such a new science at the time. Lives could have been saved.

[6S.Manu]

True but it gets you home a broken one doesn't
That's right.

Please try to understand that my target here is not having Spitfires losing wings at every turn... it's having a player who must take care of that as the real pilots did.

[bongodriver]

That's right.

Please try to understand that my target here is not having Spitfires' losing wings at every turn... it's having a player who must take care of that as the real pilots did.

Hopefully not just the Spitfire, the 109 had particularily weak wing roots I believe....but hopefully we will get a whole new thread about that one.

[6S.Manu]

Hopefully not just the Spitfire, the 109 had particularily weak wing roots I believe....but hopefully we will get a whole new thread about that one.
Of course!! But it's seems that some people really don't care about having a realistic sim.

[bongodriver]

I sure they know it. Everyone of those Spitfires is modified so that it does not have the instability of the early marks.

Damn shame they did not have standards in place and that stability and control was such a new science at the time. Lives could have been saved.

Rubbish......or BALONEY as you like to put it...

Heres the Airworthiness approval notes from the CAA on 2 different Mk 1 Spitfires which are flying today, note the modifications do not include anything with regards to stability issues.

http://www.caa.co.uk/AANDocs/29100/29100000000.pdf

http://www.caa.co.uk/AANDocs/29337/29337000000.pdf

I know you are going to come straight back with the 'look, it says no intentional spinning' but that is a blanket ban on permit to fly aircraft for similar reasons to the RAF's operational reasons during the war, an unnecessary and risky manouver and the aircraft are very expensive.

Heres Dave Gilmour of Pink Floyds old mustang permit......we all know they were allowed to spin right?

http://www.caa.co.uk/AANDocs/25986/25986000000.pdf

and another

http://www.caa.co.uk/AANDocs/28790/28790000000.pdf

Heres a 109 permit

http://www.caa.co.uk/AANDocs/22658/22658000000.pdf

the CAA airworthiness notes database search, check it out, quite interesting

http://www.caa.co.uk/application.aspx?catid=340&pagetype=65&appid=10

[bongodriver]

Of course!! But it's seems that some people really don't care about having a realistic sim.

Yes, and I've been argueing with them for 70 odd pages now.

[Crumpp]

They restricted the CG.

http://img594.imageshack.us/img594/9992/modernspitfirecg.jpg (http://imageshack.us/photo/my-images/594/modernspitfirecg.jpg/)

The Spitfire is placarded against spinning.

......we all know they were allowed to spin right?


His Mustang is prohibited from spinning too.

I know you are going to come straight back with the 'look, it says no intentional spinning' but that is a blanket ban on permit to fly aircraft for similar reasons to the RAF's operational reasons during the war, an unnecessary and risky manouver and the aircraft are very expensive.


Of course, nothing to do with the original aircraft being placarded.

[bongodriver]

They restricted the CG.



By how much? I think you will find the CoG is probably different because there are no guns or ammo, anyway the point is proved that you were wrong and 'no' modifications such as you claimed were carried out.


The Spitfire is placarded against spinning.


Just like many other aircraft


His Mustang is prohibited from spinning too.


Yes, that's what I'm saying, why have you made this comment?


Of course, nothing to do with the original aircraft being placarded.


But everything to do with the reasons why I mentioned.

[MiG-3U]

By how much? I think you will find the CoG is probably different because there are no guns or ammo, anyway the point is proved that you were wrong and 'no' modifications such as you claimed were carried out.

Thanks for posting the CAA links!

The CoG limits are exactly the same as given in the revised manual for the standard elevator without inertia device and with DeHavilland propeller. At normal service load the CoG was around 7.7" aft datum point so there was no need for the bob weight. Without the seat armour and weapons the CoG is of course even more forward.

However, the NACA tested Spitfire had the Rotol propeller which was more sensitive for the CoG due to lighter blades, hence the aft limit was 7.5" aft datum point without bob weight and NACA had the CoG at 7.8". In other words such loading was not allowed without bob weigh according to revised CoG limits. Also the Spitfire II manual quoted many times here is for the Rotol propeller, hence the warnings before the CoG limits were revised. The manual for the DeHavilland propelled aircraft and the later revisions, after the CoG limits were revised, do not contain such warnings.

Now, we have here about 70 pages of some members (apparently all from blue side for one reason or another) demanding that the stability and elevator control of the early Spitfires should be modeled according to the worst case scenario; Rotol propeller and the CoG behind the limits for such combination :)

BTW wasn't there some one claiming that the all currently flying Spitfires have the bob weighs?

[Glider]

Curiosity and research for detail are silly questions?... tell me you're not an historian...

I do consider myself to be an amature historian, which is why I always have some substance behind my theory and statement. It may not be everything everyone want but there is something.

Lets take the example of the bending of the wings. Crumps says this happened a lot and there were piles of wings to be repaired. My belief is that this happened in late 1944 when Spitfires were being used for tassks way beyond what they were designed for. I produced two different sources both of which are very clear and invite Crumpp to supply his evidence that this happened in the BOB. Result silence.
I could have pointed out that the fix was very simple, clip the wings of the SPitfire as thats what they did in 1944. If bending had been a problem in the BOB then the solution would have been quick and effective, clip the wings of the Mk I and II spits. I could have pointed out that this wasn't done and that would indicate that there wasn't a problem with the bending of the wings. But I didn't, why, because I wouldn't say such a thing without proof.



And you call this evidence!?!?
Its more than you have put forward. You have a theory but nothing behind it


What about the M S book having the same source of "Spitfire at war" => AAIB?
Possible but very unlikely. The reports are procduced during the war, the book many years later.



Now if the AAIB data is not usefull to understand the real rate of structural damage, since it ignores the accident over the sea and in enemy territory, what is the meaning to post it?
The real numbers are different, period, since we don't know how many poor guys died for overstressed airframe and they were filed as KIA because of the enemy.
There is no way they can know for certainty as to what happened in some cases over german held areas. However you accuse them of ignoring accidents which is insulting and you do it without evidence which compounds the insult.
You are also factually wrong. The vast majority of Typhoon losses due to the loss of the tail happened over Germany areas but this wasn't ignored. The pilots were aware of what was going on, it was reported and the issue was addressed. To pretend that Spits breaking up would be ignored is clearly wrong and without evidence again insulting.
You may well question my approach to historical facts but I would never, ever, say such a thing without something to support what I said.
I await your supporting evidence with some interest, note evidence not theory. It shouldn't be difficult as you believe it happended so often finding an unexplained loss that was put forward and then ignored should be straight forward.



Really? I ask it because I don't know... I would like a doc by the Air Ministry stating that every accident need to be investigated officialy by the AAIB.

Or if Mr.Newton said "We had to investigate every accident during the war" it would be enough. But it does not say it... so sorry if I've some silly doubt.
If you want that then I suggest you go and look for it. Of course you can have a theory but a theory it remains unless and until you can support it. The AAAIB can only look at things that are referred to them, it always was and should always be that any unexplained accident should be reported to them. You forget that its in the interest of the pilots and crew to report these incidents as their lives are on the line

Then that number about the rate of Spitfires lost for airframe damage is almost useless since it's a small sample mostly no related to combat. That was my first statement.
Its not a small sample it all the incidents that were reported to them. If you believe that there were others that were ignored then support that statement. Again without evidence its a theory without support


In enemy territory, in combat, numbers can easily be different. Are numbers about accidents because of clouds really important when they did fight at 5km??? Does the pilot need to land in the fog in enemy territory?
This I have already covered


So lets stick to the data about stick forces, oversensivity, AoA e structural limits and lets try to analyse them together. Without the necessity to bring on numbers and reports who do not help.
Or is that pilot reports, test pilot reports, test establishments reports and official accidents reports that are to be ignored because they are inconvenient?


Mainly because THEY DID NOT FLY AS WE DO IN THE SIM.
I don't hear Crumpp, yourself or anyone else demanding that the Spitfire be easy to land, easy to take off, be faultless in a turn and always turning inside the Me109 as did the German pilots and test establishments or are you in favour of such realistic factors

[Crumpp]

The Spitfires listed by bongodriver have Merlin 35 engines. The Merlin 35 engine is ~1550lbs dry weight. I did not catch that.

The Merlin III is 1375lbs dry weight.

The Merlin 35 is a post war engine and adds considerable weight to the front of the airplane shifting the CG forward.

The guns are removed along with all of the magazine, heating, and ducting also shifts the CG forward.

You can bet the new limits are not unstable or netural at any point.

It would be interesting to see the new weight and balance of the modern Spitfires.

[Crumpp]

If bending had been a problem in the BOB


Bending was a problem in the BoB. The RAF wanted it investigated and fixed. In August 1940, they provided a test aircraft to meet that goal.

[bongodriver]

The Spitfires listed by bongodriver have Merlin 35 engines. The Merlin 35 engine is ~1550lbs dry weight. I did not catch that.

The Merlin III is 1375lbs dry weight.

The Merlin 35 is a post war engine and adds considerable weight to the front of the airplane shifting the CG forward.

The guns are removed along with all of the magazine, heating, and ducting also shifts the CG forward.

You can bet the new limits are not unstable or netural at any point.

It would be interesting to see the new weight and balance of the modern Spitfires.

But haven't you been maintaining that the CoG is not the bigger issue with the Spitfires stability problems?

[NZtyphoon]

Just going thru the list in Morgan and Shacklady, I have counted 13 structural failures so far and I am only halfway thru the Mark I list.

It was serious enough that X4228 went to Farnborough on 24-8-40 to be used in testing to discover the cause of wing structure failures.


Serial Numbers please, and please scan and post the relevant pages. How many of them were elderly airframes in OTUs?

There was no Spitfire I serialed X4228

[41Sqn_Banks]

Bending was a problem in the BoB. The RAF wanted it investigated and fixed. In August 1940, they provided a test aircraft to meet that goal.

Source?