I hope an RAE evaluation is admissable, don't forget the British had no concept of stability and control :grin:

Stability and Control characteristics of the Early Mark Spitfires

That is the name of the thread.

Seems once again you didn't read it. Why you guys don't open a new one ?

You do realise that Crumpp has made lots of assertions in his first posting which do, in fact, make them part of this thread and a matter for legitimate debate? His claims about the so-called lack of stability and control standards for all countries apart from the good ol US of A and Germany are ridiculous and call into question his neutrality in this thread.

As for the Spitfire - of course it wasn't perfect, and I have never tried to make out that it was; however, the NACA report makes it quite clear that there was some doubt about the correct cg position as measured by NACA, and that should be sufficient reason to question its conclusions.

Also, as a fighter, it was in good in good company:

http://i91.photobucket.com/albums/k3...7-page-001.jpg

http://i91.photobucket.com/albums/k3...7-page-002.jpg

most pilots reported that the F8F was an excellent aircraft to fly and fight in, yet there was a certain amount of longitudinal instability. It would seem that a well designed fighter could exhibit some longitudinal instability as long as it could be controlled.

Since they state that a captured 109 is inferior to the Hurricane as fighter, then I wonder what are the mandatory characteristics of an airplane they want to call it "fighter".

No problem... British still drive on the left side of the road.. it's a matter of preference. :-D

But they didn't really say that did they, they just say the 109 is less manouverable.....a reasonable handicap as a dogfighter.

we drive on the left for a historic reason not really preference or because we have 2 heads and 6 fingers on each hand :grin:

You guys should put the 109 stuff in a separate thread.

And so do the Japanese. My car is a grey import from Japan. Great car too. ;)

The Bf-109 is another thread.

This one is about the measured flying qualities of the early mark Spitfire. That means the ones in the game.

The British did not have Stability and Control Standards during World War II. Only the United States and Germany had them in place.

To determine flying qualities, the RAE relied upon the individual talent of the design firm and the opinion of its test pilots.

http://img15.imageshack.us/img15/890...fastandard.jpg

I just want to point something out here: Adding instability does not necessarily make the aircraft more maneuverable.

Perfect example is the B-2 Spirit. Extremely unstable, but not particularly maneuverable.

Thank you again Lane for posting those documents.

Problem is on a few in the discussion even understand the topic. For many it is a emotional affair riddled with fear their favorite gameshape will be somehow ruined.

I did not read the report but did look over the graphs from Lane's post. Here is what those graphs are telling us about the Spitfires Longitudinal stability in various conditions of flight.

Negative stability is divergent. Co-efficient of moment and Co-efficient of lift have an inverse relationship in a stable airplane. You can look at the Co-efficient of moment against Co-efficient of Lift plots in the other report Lane posted and see the slope is positive.

What does that mean in plain english. As the wing approaches CLmax, the Coefficient of Moment is well into the negative values and wants to push the nose down. Therefore, the pilot must pull the stick back to keep the nose up.

In a positive slope, as the wing approaches CLmax, the Coefficient of Moment is high in the positive values and wants to push the nose up. Therefore, the pilot has to push forward on the stick to keep the nose down.

This is confirmed behavior in our test flight document below.

Exactly. Instability does not do anything except make the aircraft harder to control.

It is a myth that instability has positive effects on maneuverability. In fact, it narrows the maneuvering envelope because the pilot cannot precisely control the aircraft.

:rolleyes:

31.4% MAC is quite clear.

This is what I got from the report as well, but what I wasn't sure about was the difference between columns 1 and 2. Did they just run 2 trials at each flight condition and those are the results?

Additionally, it seems odd to me that in the "Engine Off" case, it appears stable in trials 5, 6, and 7 but #8 is not stable. All the other variable appear to be the same (flaps+gear are up, altitude is the same, trim set to -7.5).

Anybody know why that would be the case?

You do know it's a bomber? It's extremely unstable longitudinally and if it wasn't for the computers toning down its controls it would be extremely sensitive in pitch.

So if this is true why was the Spitfire 'known' for it's ease of control?

Interesting, yet when they wanted to increase the Spitfire roll rate they had to make it less laterally stable by clipping it's wings, so not such a myth about instability, seriously think about it, stability is a resistance to change, stability will never be conducive to manouverability, neutral to slight instability would be the ideal (which is approx where the Spitfire is) and high instability starts to require computers for control.

Even your average R/C flyer could tell you just how much rubbish the above statement is.

You don't win aerobatic championships by flying an inherently stable trainer.

Nor can you fly an aerobatic championship winning aircraft hands off for very long.

As to the Spit being 'easy to fly', the key word which is always missing is 'relatively'. Otherwise anyone with a pilots licence could've been selected for fighter training . They weren't. There was a rigorous selection procedure which many pilots did not get through and were sent to other, non-fighter training units.

I still fail to realise what your thread is trying to prove.

Heres a couple of links that clearly show the relationship between stability and maneuverability i.e. the relationship is inverse, this is what USN student pilots are being taught, I am fairly sure the USN currently are using 'adopted' standards :rolleyes:

http://navyflightmanuals.tpub.com/P-1231/P-12310068.htm

http://navyflightmanuals.tpub.com/P-1231/P-12310031.htm

So lets get all this in perspective, longitudinal instability does 'not' mean the aircraft is difficult to control, and it 'does' mean the aircraft is more manouverable, it's all about how far on the scale you go, and the Spitfire just sits on the slightly unstable end, the 109 would sit slightly on the stable end.

I will just quote Crumpp again so you can draw your own conclusions wether he really knows what he is talking about or just has a sinister agenda.

NO NO and NOOOOO

Two of the most manoeuvrable fighters today are perfectly stables: Mig29 and Su27.

It's a matter of philosophy from the manufacturer and the air forces using it.

Today, aft positioned CG is used to lower the drag in high AoA configuration : less elev surfaces deflection (especially in the case of elevons), less tail plane surface, less drag when deflected. Have a look at the range of tailplane incidences available on modern fighters (when they do not act as airbrake).

Moreover I suspect you are mixing stability (or the lack of it) and relaxed stability (what you call instability). The former is what ease the plane in flight for the pilot and, in the case of modern plane with relaxed pitch stability, is always implemented by the flight controls (the pitch crl of F16 and airbus is ctrled by the number of inputs basically - you don't have to pull and push), and relaxed stability (akka positive longitudinal instability) used in modern fighter and Airbus airliner to reduce the drag, accelerate the pitch rate or both.

I don't see why a pilot would want an unstable aircraft especially in pitch when you have to do lengthy flight in clouds, bad weather or simply T.O at dusk . There was the same prob with the Camel during WWI. they made it instable "in purpose" to give him a way to fight the superior airfoil section used by the Germans but at a very high cost : pilot SA dramatically dropped. And there we had teh same result: Experienced pilots were at ease in that situation but rookies had all their attention drown in flying the plane. Doesn't it remind you something ? ... Like section leaders landing back to base with both his wingmen shot down as depicted in a famous 1969 movie?

... And the 47 and the 51 over Europe have told us that you don't win a war with experteen but with a range of perfectly trained young pilots at ease in planes easy to master.

Regarding the Cessna, if you really push and turn the yoke My memory tell me that the 172 is quite manoeuvrable. I won't hve had a dogfight with a 29 but still you feel secure in mountainous terrains.

Yes, but release the yoke and the Cessna returns to normal flight due to its stability.

exactly and you get very tired very quickly wrestling a stable aircraft around the sky.

the 29 is practically obsolete, the 29's inherent stability is why it no longer competes against modern fighters, and the 27 is fly-by-wire.

mainly because it gives the edge in a dogfight because of the increased maneverability, I'm fairly sure flying in cloud is not a high priority in fighter design.

Skimming this thread, it seem that the Spitfire was longitudinally unstable in a narrow technical sense, which primarily manifested itself as a perceived sensitivity to elevator input.

However, the aircraft had generally good handling properties and pilots on both sides actually regarded it as rather easy to fly. In fact, it was successfully used by low-hours pilots without problem, so clearly the technical instability had either very little or no impact on its real-world use.

Can this be represented in a game? No, not unless the game forces the use of full-size force feedback joysticks and prevents players using response curves.

We should note that words like "instability" can have a narrow technical meaning that is rather different from their normal everyday meaning. Crumpp would have avoided a lot of confusion, much of it his own, if he had made this distinction clear from the beginning.

Again You are mixing instability and relaxed stability.

instability would make the plane depart itself from its velocity vector

relaxed stability is implemented in the design but ctrl the plane trough a computer. And there is a raison to that.

Exemple :

Stable or FBW stable F16 Rookie pilot: 400Kts, pull 6G -> Black out -> the plane unload by itself. Pilot woke up 10 sec after safely

Taildraggernut design instable "NutShark Uber Killer 2121" aircraft with Tomcat pilot : 400kts, pull 6G, Black out -> the plane continue to tighten the turn untill what remain of Tomcat'brain is crushed. Pilot CTG 10 sec latter.

Note:
- The 27 does not have FBW implemented. Only latter vers have pitch ctrll.
- Good luck trying to teach NATO or US fighters pilots that the 29 is obsolete. You might have the same kill rate ratio as them in BFM ;)

Quoted for the absolute and glaring truth of the whole matter, but I would argue that confusion is perhaps what the aim of Crumpp's thread is all about, confuse everyone with science so they feel insecure about opposing your position and I think that is almost as glaringly obvious.

I'm not mixing anything.....but with a statement like yours I think you are mixing some volatile chemicals right now.

p.s. the Su-27 had a 'pitch only' fly by wire

http://www.milavia.net/aircraft/su-27/su-27.htm

:shock::shock:
Rgr that TDN, hve fun

Really guy??

Obviously you have not read much of the documentation in this thread or seen the Cm over Cl plots.

:rolleyes:

Feel free to point out where the manual states a fighter should be unstable.

Thank you.

OK, now you're back please answer my question, this is the third time.

What is the purpose of this thread, and what are you trying to prove?

Edit: Sheesh, the bloke mustn't read very much. He's gone again.

Ok, take time to very very carefully understand the point, it clearly shows how slight instability is beneficial for maneuverability....a desireable quality in a dogfighter yes? at no point have I said a fighter 'needs' to be unstable, if it is a ground pounder then stability is probably a desireable quality, if it is an interceptor then it is also probably good to be stable, but a pure air defence dogfighter would benefit greatly from being able to outmanouver an opponent.

Youre welcome.

Maybe we should substitute the word 'manoeuvrability' for a graph demonstrating degrees of deviation per ounce of pilot effort in all axes at a given airspeed, followed by a graph showing time taken to return to normal flight following a release of the controls at a given airspeed (if at all), followed by some really patronising :rolleyes: emoticons.

Maybe then he'd get it. Then again, maybe not.

Wrong, once again: the RAE did indeed have standards and supplied these to the aviation industry:
http://i91.photobucket.com/albums/k3...arpe/001-1.jpg

http://i91.photobucket.com/albums/k3...harpe/009a.jpg

During WW2, however, the demands of production testing thousands of aircraft meant that each factory adopted its own techniques, designed to test aircraft to an acceptable standard, as quickly as possible, before delivery: this did not mean that there wasn't a standard set by the RAE, simply a divergence of ways in which it was done at a production level. The same thing happened in the 'States, each factory adopted a testing regime broadly following the NACA guidelines.

I feel "standards" can be misleading. How should a fighter be?

Standards are used to hold down the aircraft characteristics with an "ideal one" in mind.

But as Tomcat says "It's a matter of philosophy from the manufacturer and the air forces using it."

So the longitudinal instability of an airplane can be required by some airforces (more or less instability) and totally avoided by other.

One can produce an highly dangerous airplane that is really effective (look at the Tempest) while other can design a safer plane that influences greatly the pilot's range of manoeuvre.

In my opionion this thread demostrate that Spitfire had some characterics who actually were dangerous if the pilot was not experienced... the ability to reach a great amount AoA in so little time (given the low stick forces) CAN BE dangerous if the pilot is not really well trained. Above all if the manoeuvres were made by sharp actions on the stick. The pre-stall warning could easily alerts the pilot if he was entering in the turn smoothly, but since it raised only a pair of mph over the stall speed I really don't think that it could be recognizable during a sharp turn that could easily end in a violent stall.

Because of this there were pilots afraid to turn tightly.

It's like the drifting capability of a car: some capable pilots can recognize the limit and containing a loose car from spinning but an average pilot will not always succeed in it and will find himself with the car pointed at the wrong way.

Then we can talk of "aiming" in a longitudinal unstable aircraft...

Like I said before... Now all we need is for some data for the actual in game aircraft, instead of a MK I that is too early and a MK V which is too late...

:rolleyes:

It's Ok to have an oppinnion, my oppinion is that the stability was not a problem given the actual pilots who were flying the aircraft at the time had the bare minimum time on type and weren't ripping the wings off the aircraft, just my oppinion but the Spitfire was not famed for being an aircraft 'only experts' could fly.....quite the opposite in fact.

About stability, the best one could have in a fighter is neither stable or instable but neutral stability, afaik.

It is of course no problem to fly the Spitfire, with it's quirks, safely, especially when you have the tactile feedback that we are missing in game.
But that doesn't change the facts that only about 19mm stick travel were needed to pull 3 g, and that the stick had to be released immediatly after to hold 3g and not further increase the g-load.
For the ailerons instead a much larger stick travel was needed to gain similar results.
The missing harmony must be reflected in game, regardless about that, that many will be gaming the game and correct the joystick profiles accordingly.

Nice find NZtyphoon!

You do have a point there winny...

I've not said it could be only flown by experts: I'm saying that only experts could fly it at its limits. It was a easy plane to fly below those limits.

As this is true for any plane, IMO it's easier to gain confidence in a plane who actually doesn't allow you to fly it in a wrong way than a plane who does not put limits to the pilot's input.

But involuntary spins actually happened, and some pilots were so afraid of it that they could not outturn a 109 flown by a RAF pilot (enough confident in his new ride but, imo, not as the pilots who were flying it all the time).

And more, are longitudinal and lateral oscillations in the game?

Indeed, from here:

http://www.wwiiaircraftperformance.o...aerobatics.jpg

The Spitfire was flown by pilots who were not well trained by modern standards. The need to get pilots into action meant that training was relatively short and pilots were entering action with only a few hundred hour on type. However, I'm not aware of accounts describing the Spitfire's elevator response as a major challenge to the pilot. I'm certainly not aware of any reports of pilots pulling the wings off or losing control because of the elevator response. It would be interesting to find some if they exist.

I suspect some of the confusion evident in this thread is because:

i) Some posters (including, it appears, the OP) seem to regard stability as existing only in extreme values, so that an aircraft is either stable and thus perfectly safe, or unstable and thus horribly dangerous. However, the truth seems to be that while the Spitfire was indeed longitudinally unstable, this instability presented almost no problems even for relatively inexperienced pilots. IIRC, one of Crumpp's posts also describes the DC-3 as being unstable. Again, it probably was, but there is little evidence that this caused problems for its pilots. In fact, it's worth noting that most aircraft actually are spirally unstable (i.e., left to themselves they will ultimately end up in a spiral dive), but the instability mode is so slow to develop that the pilot isn't even usually aware of it.

ii) Some posters regard instability as a desireable characteristic for a fighter aircraft as if it promotes manoeuvrability. But in technical language "unstable" is not the opposite of "unmanoeuvrable" (if by the latter we mean not agile). An aircraft can be simultaneously unstable and unmanoeuvrable (DC-3), or it can be stable and manoeuvrable (Pitts Special) or it can be unstable and manoeuvrable (Spitfire), or stable and unmanoeuvrable (almost any large aircraft). Unfortunately, popular accounts and casual useage mix these terms up and sometimes use unstable to mean manoeuvrable, or imply that instability is necessary for manoeuvrability. It isn't.

Whether any of this can be represented in a flight sim is a different matter. The lack of force-feedback, short PC joysticks and the need to allow response curves all suggest to me that it would be tricky at best.

FWIW, there have been attempts to relate the pilot's experience of how easy an aircraft is to fly to deficiences in stability or other aerodynamic deficiencies of the design. One such method is the Cooper-Harper scale for evaluating aircraft flying qualities (often used by test pilots). The scale considers the aircraft characteristics and how they impose demands on the pilot in selected tasks or required operation. The scale runs from 1 (good) to 10 (very bad), with 1 defined as "pilot compensation is not a factor in desired performance" and 10 meaning that "control will be lost during some portion of required operation". On the scale, 3 is defined as an aircraft characteristic which exhibits "some mildly unpleasant deficiencies" and imposes demands on the pilot such that "minimal pilot compensation (is) required for desired performance". The scale defines 4 as requiring "moderate pilot compensation". The division between deficiencies warranting improvement is at the 3/4 boundary (not required for 1-3, required for 4-10). I suspect that the longitudinal instability of the early Spitfire if assessed on the scale would be on that 3/4 boundary - i.e., it warranted improvement but was not seen as a major deficiency.

It would have been useful if the OP had clarified some if these matters at the start.

Some shady lawyers use the same tactics in court.. It is the kitchen sink approach where they through everything at the wall and go with what ever sticks.. And during the process they hope and pray that everyones focus is on all the things that didn't stick and hit the floor

Isn't that the same tactic as the one you are using now, AoA?

The very first line from the very first link you posted says the following:

My eyes hurt from rolling so hard.

see you didn't get past the first line then.

Just like Sandstone pointed out above: Everyone thinks that maneuverability requires instability. That is false, and even the US Navy says so.

Otherwise, they would not have described the T-45 as "very stable yet fully maneuverable". A child can understand this.

A child would be able to read to paragraph 5, unlike yourself it appears.

Nada, nicks, nine, nope

I read the entire article. Are you denying that a stable aircraft can be maneuverable?

Sure it has to able to maneuver. It is not a V1 and flies one direction only.

no, not at all, but i agree with the US Navy when they say in paragraph 5,

are you denying them?

Cool, glad we agree that a maneuverable aircraft does not require negative stability.

I'll ask again Doggles,

are you denying them?

You're in bongodriver's squad, right? Nope, I won't be debating with you.

If someone else wants to ask me that question I'll maybe discuss things with that person.

Have a nice day!

ahhh, didn't answer the question, huge surprise, silence speaks volumes.

for the record, because we're in the same squad, doesn't mean we agree on everything.:rolleyes:

--

Yeah I agree, I don't like him either. He reflects very poorly on your squad's reputation.

Have a nice day!

wow, you're mature.

kindergarten stuff.

not saying much for JG13 yourself mate.

Okay, if you ain't interested in answering fruitbat's question 'cos you don't like bongodriver I'll ask;

Do you agree with the statement

"In a word, the relationship of longitudinal stability to maneuverability is inverse. As one increases, the other decreases and vice versa." ?

This is a bit of a loaded statement. It ignores half of the argument.

The question is: Is a stable aircraft more or less maneuverable than an unstable one. Of course you can have a maneuverable stable aircraft but, are unstable aircraft more maneuverable than that?

The other big question is how detrimental to the Spitfires performance was the instability?

exactly.

First of all, I'm going to disregard things like Active Stability, where you have the computer making lightning-quick corrections to the unstable aircraft to keep it in controlled flight, because I think that this is beyond the scope of what we're talking about here. If we want to get into a discussion on the characteristics of FBW systems and supermaneuverability then we should open a new thread.

--

I think it depends greatly on

a) which stability mode we're considering; if it's the short period or the phugoid mode

and

b) what you consider to be "maneuverable".

I think that if you were to reword that statement to read "the relationship of longitudinal stability to agility is inverse. As one increases, the other decreases and vice versa" then I would absolutely agree.

If an aircraft is unstable, then it will by definition be difficult or impossible for the pilot to precisely control the aircraft during a maneuver. By this I mean the pilot won't be able to hold a constant G-level through a turn, or to keep his guns on target.

I would consider such an aircraft to be highly agile, because it can re-orient its lift and nose vectors quickly and easily. This makes intuitive sense, because an unstable aircraft always wants to depart from equilibrium.

But I don't think that the aforementioned aircraft is particularly maneuverable, because I would define maneuverability as being easy to maneuver precisely and accurately through a wide range of maneuvers. In my opinion, if you have to fight the aircraft making corrections the whole time, then it's harder to get it to do what you want it to do, and so it's not very maneuverable, and so I would not consider an aircraft with negative stability to be very maneuverable.

Coming back to the Navy textbook quote and FBW systems for a moment:

I think that they ascribe an inverse relationship to stability vs maneuverability because their aircraft have FBW capabilities. If the airframe is actually unstable, but you have a computer making corrections thousands of times per second, then all of a sudden your aircraft appears very stable to the pilot. In this context, the quote is accurate.

Obviously this lets them combine agility and maneuverability into one, and I think this is why the quote says what it does.

Here's a quote written about the F-16

The CG is located aft of the aerodynamic center to reduce longitudinal stability
in favor of maneuverability, and help the horizontal tail
add to the lift while maintaining longitudinal trim...

From : JOURNAL OF AEROSPACE SCIENCES & TECHNOLOGIES VOL. 58, No. 2

Fair enough, we are discussing an aircraft without FBW and supermanœvreability

I don't see any indications of pilots having to "fight" the Spitfire all the time, so it wouldn't come into your definition of agile but not manœuvreble -

Here are some comments from Alex Henshaw on flying the Spitfire:
http://www.theaviationindex.com/publ...pilots-defence

"With a brief pause for the undercarriage to retract and at 135 m.p.h IAS, the machine would be pulled up into a vertical climb for the first half of a loop. On reaching almost the extremity of the climb it could then be gently coaxed over at something like 10-15 m.p.h below its normal stalling speed. During this sensitive manœuvre the ailerons would be hard up against the stops but still effective....
The Spitfire would then continue with a series of loops and half-rolls to gain height over the airfield to between 4,000 and 5,000ft. Depending on the precise position of the aircraft in relation to the airfield, the usual procedure was to dive to 450-470 mph in front of the flight shed and then pull out and complete an upward roll to the left, one to the right and a half-roll left. This manœuvre might be repeated or continued with a vertical dive with aileron turns."

"It is generally accepted that the Hurricane made a better gun platform than the Spitfire. I have never fired the guns of a Hurricane, but those top-scoring pilots with whom I have discussed the subject all say that the marvellous feature of the Spitfire was the speed at which the guns could be brought to bear on the target. Their reply to the accusation of "hosing' was that the pilot concerned was a poor shot."

I'd like to repeat that being unstable or negative stability is NOT desirable for any airplane, as the pilot, or today electronics and hydraulics, have to work all the time for a controlled flight.
For commercial planes, were safety is the highest priority, positive stability is desirable.
For fighters, or aerobatic planes, neutral stability is the non plus ultra.

:rolleyes:

Once again, a standard is a standard. The Air Ministry and the RAE did not have one.

The United States had a standard during the war. That does not mean every airplane met that standard. Most aircraft were designed before the standard was adopted. It does mean, they designed to meet, tested to meet it, and implemented design corrections to meet the adopted standard. Part of that report and standard is included in the very first post in this thread.

The design firms in the United States were obligated to meet a standard. Supermarine was under NO Obligation to correct the Spitfire. It as already in production and service. It took the NACA, Gates, and mounds of evidence of the instability before a simple correction was adopted.

With the right information, figuring out how much weight to add to your elevator bellcrank is no different than a weight and balance. Once more, a designer can add springs, bungees, weights, and other devices to increase or decrease the control force as he wants.

Facts are the RAE relied upon the individual talent of the engineers and the opinion of the pilots.

Not all engineers are equal. For example, Sir Sydney Camm was very talented with stability and control design. His designs reflect that. RJ Mitchell certainly missed the mark on the Spitfire.


It does not matter how maneuverable an aircraft is if the pilot cannot control it.


That is the Spitfire's issue. Nobody is claiming it should be less maneuverable. The longitudinal axis should be so maneuverable as to be very difficult to precisely control.

Generally speaking, all aircraft above Va can exceed their airframe limitations. You can do it more easily in the Spitfire.

It is also harder to precisely control in a turn. The strength of the buffet determines the scope of the effects of the stick shaker zone. Hitting stick shaker in a Spitfire is easier due to the longitudinal instability.

Properly modeled, the Spitfire has world beating performance. While not the most agile fighter, it is fast, climbs well, and excellent rate of steady state turn.

The majority of fighter pilots in World War II never got into a single dogfight. Most kills occurred without the "victim" even knowing the opponent was there behind them.

So all those anecdotes about "easy to fly" are worthless without the context and a comparison of pilot skill. I would love to fly a Spitfire and throw it around the sky on a sunny afternoon.

That is not the same as dog fighting. Dogfighting is what you do in this game and it has very little if anything at all to do with the actual events or history. An actual simulation of WWII would be zero fun. For the vast majority of pilots, it was lots of tedious flying to be killed without ever seeing who did it. For a few, it was a few seconds of terrified maneuvering before death and for a rare few that we still talk about today, the thrill of the hunt.

The NACA and the RAE agree that the aircraft was difficult to precisely control in a turn. It was twitchy airplane. The airplanes characteristics are measureable, definable, and everyone who was involved with the airplane agreed upon them.

The Spitfire should take time and skill to master. Once mastered, reward its aficionados with the performance they expect.


I think this thread has about run its course. Time to submitt the bugtracker.

Please start into my use of "stick shaker"....

:grin:

How many actual dogfights did Henshaw get into in an early mark Spitfire??

None.

How many in any Spitfire??

What Mark of Spitfire is that on the magazine cover?? What Mark was the topic of this thread??

Exactly

Absolute nonsense, once again Crumpp - you clearly have no clues as to how the British aviation industry operated in wartime. Where is your evidence that Supermarine was under no obligation to correct the Spitfire?

How did NA comply with the "standard" when they fitted the P-51B/C/D with rear fuel tanks, thus turning the machine into one that was highly unstable when the tank was full? Was the "standard" adopted before or after the P-51 was designed; before or after the modifications to the P-51?

How did Grumman correct the undesirable elevator characteristics of the F8F-1 to meet NACA standards? Was the "standard" adopted before or after the F8F was designed?

What does it matter how many dogfights Henshaw got into - how many have you got into? How many Spitfires have you flown? And since when has this thread been a discussion on dogfighting in the Spitfire anyway?

Nor does the mark of Spitfire on the cover have anything to do with the article.

http://img843.imageshack.us/img843/8...fastandard.jpg

They knew about it in 1936!! Do you really think Supermarine is that stupid it took them four years to fix it???

It cost's money to add things to an airplane. Even more money to fix an issue that is the designers fault.

Who knew about what in 1936? and no Supermarine were not stupid. And what relevance does the last statement have to with anything?

They restricted its use when full to non-combat flying. It was prohibited to dogfight with a specified amount of fuel in the tank.

That was so the CG would be within specs......

So, NA issued instructions to the pilot - isn't that exactly what Supermarine did in their Pilot's Notes?

And again I ask where is your evidence that Supermarine was not obligated to "correct" the Spitfire - what were they doing when they added bob-weights and later modified the elevator?

Of course....

NA said don't fight the aircraft and use the 25 gallons of fuel in the tank first in an airplane that will burn 26 gallons climbing to 11,000 feet.


Supermarine said, "It is messed up, deal with it by careful flying."

Don't you think in a simulation, players should have to deal with it by careful flying??

So, NA can say "We messed up with the new fuel tank, don't try and be a hero flying this aircraft in this configuration" because they are complying with a standard, while Supermarine can point out that in bumpy air there may be problems at high speed because they are not complying with a standard? :rolleyes:

Nor, it seems, were they under any obligation to say anything because they knew about some undetermined problem in 1936 but decided to do nothing because it was going to cost money and it was the designer's fault anyway. :rolleyes::rolleyes:

First of all, it's been said already that not all the aircraft met the standard.

Secondly, why is it important? What difference does it make if Britain had a standard or not? Who cares? You keep bringing this Did-they/Didn't-they topic up over and over, but it's completely secondary to the purpose of this thread.

This thread is supposed to be about coming up with a good body of evidence so that the developers can add proper handling to the game. Are you saying you don't think players should have to deal with it by careful flying?

Yes, I agree, there is lots of room for improvement regarding the handling characteristics to make this game more realistic. I find flying in this sim a bit too easy in many aspects.

I'd like to see similar control lockup we have on the Hurricane on all planes, especially at 109s elevator and Spitfires ailerons. All in all, I very much like the increasing forces in the joystick as the airspeed rises, they are just somehow not balanced properly at this stage. I'd like the devs to fix the trim response (esp. elevator) so we're not able to perform this ufo-like manoeveurs anymore. I'd like them to fix the Spitfire flaps issue where you can exploit it and turn tighter if it needs be. Of course they should make the Spitfire elevator control a bit twitchier, but that o me is just another small detail. I could go for much longer with listing this small FM flaws (that is still my opinion only, ymmw).

For this particluar issue you'd need to have a proper atmosphere modelled so we can feel this bumpy air (we don't because we're flying through vacuum apparently). We would also need to have the structural G-Limits modelled so we can not do crazy stuff like we normally do. We don't have that either at this moment. Also HW issues can never be considered properly. Everybody has got different joystick and would be able to tweak the elevator curve (or sensitivity) accordingly anyway. With my game-time in the Spitfire I'd note that the plane is very unstable already compared to the 109 or G.50 or Hurricane. It requieres certain skill to control it at certain situations, e.g. keeping nose straight at the speeds close to the stall. Spitfire, she is a twitchy beast already, you'll see that when you try her a bit more ;)

You're saying this thread is about 'coming with good body of evidence' so the devs can benefit from it and perhaps fix this issue. To me as unbiased observer it rather looks like this thread is about certain people showing off with their preferences and about trying to get certain things porked. This thread is also about avoiding questions and providing selective evidence or ignoring the counterarguments. It reminds me very much of John Cleese library sketch as they provide any information by cutting the unwanted bits and bobs so the result is ''England never lost a cricket match in last 70 years.'' I am not sure if you're familiar with it but you should watch it, it's hilarious. Not as hilarious as your kindergarden post but close enough. Funniest thing is that one of this guys dosn't actualy fly this sim at all and the other (that is you Doggles) only flies Messerschmitt. None of you 2 has got a clue about Spitfire stability in game to start with. But do carry on. :grin:

Of course YOU are the unbiased observer, but there's no way that I can be unbiased, right? Because I have a 109 in my signature?

You know, it's a really sad statement when a person can't apply their relevant knowledge without being labeled as a show-off or a "luftwhiner". You think I'm showing off? I can be insulting too if I want.

Point it out, then. The only questions I've ignored are the silly ones that have no bearing on the matter, like did 1930's Britain have a stability standard.

How do you claim to know how often I fly the Spitfire? Because when I go on ATAG I prefer to fly the 109?

It's possible to change one's handle, and also possible to fly offline or on private servers.

Robo, you know I don't fly CloD so I really don't care about ingame performance (until a more realistic combar environment wuold be implemented by the devs).

Anyway I've found the info in this thread really interesting: we already know many of the historical issues of the german/japanese aircrafts (btw I would like the devs to implement the 109's takeoff/landing issues) and usually they are already in the game (at least in IL2, even if sometimes in a bad way).

Now what about the Spitfire? The only defects known by me were the negative G engine cut and the "worser weapon platform compared to Hurricane and Tempest" characteristic (but this does not tell us anything). When all we listen is "it's easy to fly", "it's like a ballerina", "the elliptical wings" ect it's nice to know that they got some more issues: for example I did'nt know of the oversensible elevator control that, imo, is a serious issue when the plane has to be flown at her limits... something that in IL2 we do a lot, but in RL usually it was not really required (so "it was easy to fly").

I didn't say that you were not unbiased. :o

I only commented on myself and I ment it like ''I don't really care about this arguments of yours, I only read this stuff to learn something new and interesting.''

That part about showing off was actually not aimed at you really but other 'certain people' :grin: I don't think you're a luftwhiner (whatever that is) and I don't care about what you have got in your signature. I read your posts and I reply sometimes. You apply your relevant knowledge and I respond, that's how forums work. It's not personal and I actually agreed with you and corrected on few things you were wrong about (according to my relevant knowledge of that matter) ;)

There was one particluar question, we both know which one that was, where you chose to avoid it in a spectacular way. But as you say that was not important.

I don't know but it's easy to assume so from your posts - like the one where you say Spitfire is just a faster Hurricane and similar. I am very sure that you have only very little experience with the Spitfire (or the RAF fighter aircraft per se) in the sim and I wondered how you feel confident to comment about it so much in this thread. And I told you so, that's all. :o

Have a good day!

Hi Manu, no worries, I know you don't fly too often and I understand why is that. I value your opinion because from 1946 I know you're experienced pilot.

I am all for it - I mentioned several major FM flaws in this sim and I stated all planes are too easy to fly at this moment, I agreed with Doggles when he said we need less generic behaviour and handling characteristics. I also said that with this particular issue (I am all for it, I will adapt easily) it's more complex than that - structural G limits and atmosphere are not modelled sufficiently for it to have desired effect.

I also find this thread very interesting and I am glad to read throught the posted documents.

As I have pointed out before Crumpp made this an integral part of his claims about the Spitfire control characteristics - that Britain's aircraft manufacturers did not have a design standard for stability and control, therefore they designed bad characteristics into aircraft such as the Spitfire and got away with it because, unlike the mighty Yanks and Germans, they were not "obligated" to correct such things; this type of claim deserves to be challenged because it shows an incomprehensible lack of knowledge from someone who claims to be an expert in aeronautical engineering! Blame Crumpp for introducing the subject in his first posting.

You'll recall that I answered that question. That answer is here. If you aren't satisfied with my answer I'm happy to discuss it with rational people. But I'm not obligated to reply to posts on this forum, and I elected not to discuss things with people who are irrational, or in the same squad as known forum trolls.

Well, just for you I went up on ATAG and shot down a 109 for you. Easy as pie.

As I was climbing up to altitude I repeated an earlier test that I'd done and, in level flight at ~10000 feet, pulled the stick back and then let go. The aircraft nosed back down gently like a stable aircraft would. It should have held that AOA until it ran out of speed (I was using the rudder to keep wings level), or possibly nosed up further, depending on if you choose to believe it had neutral or negative stability.

But I have no experience in these things, so what do I know? :rolleyes::rolleyes::rolleyes::rolleyes:

Why does it matter, though? Historical trivia does not an engineer make. You can't prove someone isn't an engineer because they haven't heard of Somebody Lanchester.

I'm an engineer and I've never heard of him before this thread.

And lastly, not that I really care, but if Britain had a unified standard in the 30s, then why is there a document from 1947 talking about developing one for the first time? I'm sure that the individual manufacturers did indeed have their own standards, but that's not being disputed.

Sorry I only recall you don't play with Jimmy because Jimmy plays with George and you don't play with George in the first place. :o

I don't mind what you're doing on atag, why exactly are you telling us this?

This is an issue indeed but as I was trying to point ou in my previous post, rather small one compared the other issues with general FM and actual aircraft FMs. I hope all of them will be addressed at some point.

Yes indeed, you have obviously very little experience with RAF aicraft in the sim, judging from what you say about them, e.g. Spitfire and Hurricane feeling the same except for the speed.

Because if I never flew the Spitfire then I'd be bad at it. I'm not.

Me too.

I was exaggerating a little bit, trying to make a point.

I still think the aircraft in this sim (109 included) feel a little generic to me.

How much fuel did you have? The evidence produced states that the spit was longitudinally stable with the CofG forward, i.e. a full tank, with decreasing longitudinal stability as the CofG moves aft with decreasing fuel load.

Personally, I'm very interested as to what the wording of the entry in the Bugtracker will be.

If Crumpp wishes to make definitive statements and claims, based on a very small amount of evidence there's no reason they cannot be challenged.

If not for you convenience then I'll answer for others - if you bothered reading the 1938 doco you'll see that aeronautical development had outstripped the standards of the time, from biplane to monoplane, such that the RAE and Air Min were working with the aircraft industry to promulgate better standards. Now, what happened during WW2? Jet aircraft, high speed prop driven aircraft approaching the speed of sound etc etc so now a new set of standards had to be developed and introduced; basically aeronautics and aeronautical engineering were changing extremely quickly from the early to mid 1930s on, so I don't believe that it was possible for even NACA to devise and stick to a definitive set of "standards" in the way Crumpp claims. Think about it - how was it possible to use the same stability and control standards for a 150 mph biplane fighter as for a 450 mph monoplane?

NzTtyphoon,

The basis for all modern stability and control was developed during World War II. Outside of Germany, the NACA was the worlds leading organization for Stability and Control.

Fredrick Lanchester did some pioneering work and is considered the foundation for stability and control. He correctly theorized on vortex theory of lift with gliders secured by wire, conceptulized aircraft oscillatory motion which he called "fleeing motion" instead of phugoid. He published several works and even spoke with the Wright Brothers in 1908.

None of this was put into any mathmatical definition. Fredrick Lanchester was not able to put his ideas into any useful mathmatical form.

I have been waiting for you to realize this since you brought it up. I have ignored most of what you write because it is obvious you argue based off emotional attachment and do not understand much of what you claim. It is another red herring like arguing for pages about a non-dimensional proportion.

:rolleyes:

Despite these apparent 'adopted' standards, both the US and Germany produced aircraft that actually 'did' have dangerous flying qualities.

So the question is, what point are you trying to make with the assertions the British had no adopted standards? that every British aircraft was just a hit or miss lucky guess? all the British aircraft that had stable qualities were just 'flukes'?

This is where you don't convince me.

The Spitfire certainly did have undesireable pitch stability, but was it enough to make it "very difficult" to control precisely? I don't think it was. I think this because pilot accounts seldom mention longitudinal stability and because low-hours pilots flew it without problem. You obviously think it was, but this interpretation doesn't seem to be backed up by much in the way of evidence and, to me at least, comes over as no more than an assertion. Certainly, nothing convincing has been presented.

You say we shouldn't consider Spitfire pilot acounts. But if we are to determine how much of a problem was actually caused to real Spitfire pilots by the stability issue then that is exactly what we have to do. I can't see any way round this.

I think the little blue sarcastic emoticon shoud be re-named Crumpp.....

According to all measured standards, it was....

The Operating Notes also reflect it as well as test pilots from England, United States, and Germany.

intersting article from NASA....

http://history.nasa.gov/monograph12/ch4.htm

Nice one, I like this bit on the SPitfire

FIGURE 4.5. Supermarine Spitfire airplane. A high-performance fighter noted for its role in the Battle of Britain and throughout WW II, the Spitfire had desirably light elevator control forces in maneuvers and near neutral longitudinal stability. Its greatest deficiency from the combat standpoint was heavy aileron forces and sluggish roll response at high speeds.

Crumpp this is a must read for you

I thought it was worth making the 'desirably' bold too ;)

Interesting to note the 'near neutral longitudinal stability' persumably this is because it was slightly longitudinaly unstable, but not unstable enough as to be regarded a problem.