Prove that you are not making a worst-case scenario out of just two documents: Prove - with documentation - that the Spitfire had such bad longitudinal stability characteristics that it affected its abilities in general flight and in combat and, above all PROVE that this can be replicated in a flight sim made for PCs.

Here is a little experiment you can do at home, NzTyphoon.

Make a paper airplane. Toss it.....

See how stable it flys.

Now add a paperclip to the nose and throw it again.

Which is more stable?

ok

The Stability and control characteristics of the Early Mark Spitfires:

Now let's look at the Spitfire in an abrupt pull out as measured by the NACA.

http://img98.imageshack.us/img98/320...ruptpullup.jpg

First thing to notice is the stick forces. There are light but acceptable in abrupt pull outs. While very steep, the slope of the curve matches our acceleration curve and the controls float without overcoming the inherent stability of the design. The steepness of the curve tells us the pilot is able to very rapidly load the airframe. In fact, the NACA had to make allowance in their stick fixed measurements to prevent damage to the aircraft from acceleration because of the rapid onset the controls allowed.

However, if we look at the acceleration curve we see an abrupt change and not the desirable smooth curve. This points to the stability characteristics contributing to the rapid fluctuations in acceleration that the aircraft exhibits under other conditions.

Next we will get into the unacceptable longitudinal stability characteristics of the design.

We will look at a condition of flight essential to a dogfighter. The ability to make abrupt turns.

The pilot must be able to precisely control the amount of acceleration he loads on the aircraft. All aircraft performance depends on velocity. In order to get maximum performance out of the aircraft above maneuvering speed, Va, he needs to be able to make a 6 G turn and not exceed that load factor to prevent damage to the airframe. Below Va, the pilot needs to control the acceleration so that he does not stall the aircraft making the abrupt maneuver as well being able to maintain a maximum performance turn.

Doing that in an early Mark Spitfire was difficult and something only a skillful pilot could perform.

First the NACA report. Abrupt 180 degree turns were conducted at various entry speeds to gauge the level of control the pilot had in maintaining steady accelerations. The turns were also done to the stall point in order to gauge the behavior and amount of control.

"In turns at speeds high enough to prevent reaching maximum lift co-efficient" means turns above Va.

http://img404.imageshack.us/img404/2525/rapidturns.jpg

http://img513.imageshack.us/img513/6480/rapidturns2.jpg

"By careful flying" a pilot can hold a steady acceleration. That agrees with the Operating Notes warning for the pilot to brace himself against the cockpit to get better control when making turns.

Now let's look at the measured results.

http://img843.imageshack.us/img843/6...dturnfig15.jpg

Here we see in a rapid left turn performed at 223 mph the test pilot is unable to hold constant acceleration on the airframe. Very small variations in stick movement and stick force changes of 1-3lbs results in large fluctuations in acceleration.

Taking two point we can compare the slope of the curves of stick input to acceleration over time.

For the intital pull up:

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.

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.


Next let's look at the pilots ability to control the accelerations in the pre-stall buffet.

http://img600.imageshack.us/img600/4313/stallbuffet.jpg

Here we see the pilot was able to load the airframe to 5G's in 1 second to reach the pre-stall buffet 3 times. The smooth positive sloped portion of the curve represents the aircraft flying while accelerations are increasing. The top of the acceleration curve represents the pre-stall buffet. The bottom of the curve represents the stall point.

The amount of stick travel as measured by the NACA was not acceptable.

http://img94.imageshack.us/img94/2621/sticktravel.jpg


Next let's look at the opinion of Stability and Control Engineers on the Early Mark Spitfires.

http://img832.imageshack.us/img832/3...sairplanes.jpg

http://img855.imageshack.us/img855/7...airplanes2.jpg

http://img825.imageshack.us/img825/4...airplanes3.jpg

http://img404.imageshack.us/img404/6...shspitfire.jpg

There is no doubt that the Air Ministry was aware of the longitudinal instability of the early mark Spitfires.

Just some of the many references to the Longitudinal instability found in all of the early Mark Spitfires.

Spitfire Mk I Operating Notes, July 1940:

http://img109.imageshack.us/img109/7976/page10jv.jpg

http://img26.imageshack.us/img26/2599/page12dh.jpg

http://img542.imageshack.us/img542/9202/page13o.jpg

http://img607.imageshack.us/img607/2471/page15j.jpg

http://img651.imageshack.us/img651/2456/page16lu.jpg

Go make your own paper aeroplanes: The NACA report concentrates on one aircraft which, in spite of your claims, may not have been correctly loaded:

http://i91.photobucket.com/albums/k3...pe/Quill4a.jpg

http://i91.photobucket.com/albums/k3...Quill2-001.jpg
http://i91.photobucket.com/albums/k3...Quill3-001.jpg

Supermarine's Chief test pilot knew more about flying the Spitfire and its capabilities and characteristics than NACA and took he took urgent action when he realised that there was a problem with badly loaded Mk Vs.

http://i91.photobucket.com/albums/k3...rpe/Quill4.jpg

You can interpret documents any way you like - fact is that there are other valid opinions which show that longitudinal stability only became a real issue when the loading instructions were ignored or misunderstood at an operational level. As for the excerpts from your book This also falls down as a source because quite clearly some basic research is missing because both the typhoon and Tempest PNs state they were slightly unstable longitudinally, and only the Hurricane could turn inside the Spitfire... as for gun platform:

http://i91.photobucket.com/albums/k3...-page-003c.jpg

The pilot's notes were read in conjunction with the Pilot's Notes General: Note that the PNG carry similar warnings to those in the Spitfire PNs see (ii) which applied to all aircraft
http://i91.photobucket.com/albums/k3...arpe/PNG3a.jpg
http://i91.photobucket.com/albums/k3...arpe/PNG4a.jpg

You have not demonstrated that you are not applying a worst-case interpretation to both the NACA flight trials and PNs.

Nor have you explained how you propose to alter the flight characteristics of a computer based flight sim to accurately replicate this so-called instability considering the plethora of different set-ups used by players.

Well, here we go again, the same stuff with flawed interpretation posted again and again.

Over and Out :)

Just like the 100 octane threads.:( Why does myopic tunnel vision come to mind?

At the very least putting a worst-case scenario on two documents while claiming that these alone are definitive proof of the Spitfire's bad longitudinal stability - when another NACA document on the Spitfire's stall characteristics was presented it was dismissed as being irrelevant:
http://i91.photobucket.com/albums/k3...-page-003a.jpg
http://i91.photobucket.com/albums/k3...-page-004a.jpg

It will be truly interesting to see how the proposed bug-tracker will define the "problem" and how it proposes to alter the Spitfire's flight characteristics to cater for a flight sim in which different equipment is used and tuned by individual players...

Its been put in on bug tracker:

http://www.il2bugtracker.com/issues/415

Alas no proof or in game tests in the bug tracker entry to indicate CLOD Spit MKI is indeed flawed in the Sim.

A lot of energy is being spent on the Mk V which most would agree had an issue that was resolved by bob weights.
There seems to be no real evidence that a problem existed in the Mk I or II which were the versions used in the BOB

LOL...Really??

Spitfire Mk I Operating Notes, July 1940:

http://img109.imageshack.us/img109/7976/page10jv.jpg

http://img26.imageshack.us/img26/2599/page12dh.jpg

http://img542.imageshack.us/img542/9202/page13o.jpg

http://img607.imageshack.us/img607/2471/page15j.jpg

http://img651.imageshack.us/img651/2456/page16lu.jpg

http://img716.imageshack.us/img716/1650/x4268.jpg


http://img855.imageshack.us/img855/4...yexplained.jpg

http://www.spitfireperformance.com/k9787-fuel.html

Unfortunately for you there is little if any evidence of any bad outcomes. The first set of well worn docs are warning that obviously worked as wing failures were rare.

In July 1941 well after the BOB investigations were started. Had it been a problem in the bob the investigations would have started a lot earlier

And you have still to supply any evidence re the piles of wings waiting repair

Well,

I can't post any pictures on bugtracker to show the documentation even using the same account as NzTyphoon.

Very Strange....

Perhaps 41 Squadron Banks who is the manager of Il2bugtracker can look into my acount settings and see if there is some reason for this.

I have tried every method available at photobucket as well as other hosting sites.

??????


http://i1256.photobucket.com/albums/...mpp1/X4268.jpg

http://i1256.photobucket.com/albums/...reserials2.jpg

http://i1256.photobucket.com/albums/...ireserials.jpg

Bug tracker is for Bugs.

Have you demonstrated that the Spit in Ver 1.08.18956 is actually bugged ? You indicated in this thread when asked about in game testing that all would be in the bugtracker post. All that is there is a series of statements replicating your posts in this thread.

I dont see any Ver 1.08.18956 test data to support your case in your bugtracker entry.

Dive to Vne and pull up. You can't break the airframe even with full rudder applied at pull up.

Make an abrupt pull up from level flight and release the stick. The airframe loads on a normal slope and gently settles.

At Vmax, make a steep bank and abrupt turn to 180 degrees from heading.

Release the stick and the turn stops. If above Va, it should increase to airframe damage and accelerated stall.

It is all measureable.

thats why i voted against it, nothing in there about how the game spit fm is wrong compared to this data.

im surprised to see there isnt one for structural damage under high g's, or is it there and i just cant find it?

J Quill in June 1941 they did tests re wing failures. So until then it wasn't a noticable issue or the tests would have started in say Oct 1939

X4381 lost a wing in a dive. Quite possible when exceeding the dive speed

X4421 lost its wings when in a high speed stall after a steep dive ignoring the pilots notes

X4354 lost its wing in Dec 1941 at an OTU when in a dive. An old aircraft in a training unit in a dive probably exceeding the dive limitations

X4381 lost its wing in an OTU in a high speed dive out of cloud. An old aircraft probably exceeding its dive limits after loss of control in a cloud

Is that the best you can do?

PS what about all those that broke up when spinning, another major weakness (according to you)

Ivan,

This is all easily seen in the math. I would think the program accounts for a Center of Gravity.

????

I never said it was complete. I counted 13 incidents only halfway thru the serial listings for the just the Mark I in Morgan and Shacklady.

There some 9 pages of this irritating tiny print. You can go through them.

Again,

The measured and defined stability and control of the early mark Spitfires is neutral to unstable at normal and aft CG.

That statement holds true for any measured results.

Unfortunately, there are only a few measured results from the United Kingdom because there was no standard in place. In otherwords, there was no ruler outside of pilot opinion.

Where do you get this stuff?

Nobody dismissed it as irrelevent. In fact, it agrees with the first NACA report.

Do you think the NACA was contridicting itself?

Did you read the report and note the conditions??

It all agrees, bud. Stop with your pointy tin foil hat theories.

I know it isn't complete and I appreciate the effort but all the ones you mention are not relevent to the case, so as I said, is this the best you can do.

Have you found any at all so far re spins, you will recall that you were once very keen saying that spits broke up in a spin and so far nothing to support it. In a similar manner we have nothing to support the piles of bent wings, or an unusual number of accidents, nothing at all. No mention of this as an issue in any of the hundreds of books that have been written about this aircraft and the BOB.

All we have is your spin of a known factor which pilots were warned of.

All we have is you making a worst case scenario out of something everyone was aware of and wasn't a major problem.

Edit - I should add that also have yet to prove that the level of instability admitted by one and all, is an unsafe level or even that it is unsuitable for a fighter.

No, all we have is a few people belitteling documented quirks of the early marks Spitfire with a energy that borders on fanatism.

The same people will probably fight with the same energy, to have all others planes quirks included in game.

Crumpps only mistake was not to start with the 109, i believe, not that this would have changed the then future Spitfire discussions, imo.

You can use the online listing, http://www.spitfires.ukf.net/production.htm

What we have is people putting forward alternative POVs, with documentation - democracy in action, yet this is belittled as "fanaticism". I see no rules stating that people cannot debate the merits or otherwise of a case put forward in a thread.

But where is your in game data ?

:rolleyes: Spare us the rhetoric and emotional appeals. That's not what democracy is and you know it.

ahh, the blue smileys are catching.

Crumpp. I do not understand actually what you want? I understand the Spit control and stability tests. I do not understand how to realize these characteristics in the game, where the players have completely different controller (stick length, stick dimensions, turning points of the aileron and elevator)? If the old, unique stick characteristics want to apply to the most common joy forms, the "historically correction" compromised in any case. Not to mention that you can change all handling characteristics with the joy softwares.

Therefore, I vote against it. Not against of historical authenticity, but the applicability in the game.

Democracy

Didn't watch the video, too busy watching the Mars landing. Democracy is a system of government. A bunch of people shouting at each other on a forum is not democracy.

You used that word because you thought it would be more persuasive.

Tom,

It is not just stick settings.

1. The aircraft moves to trim speeds but overshoots. That means it is always in motion and must be controlled.

Can it be controlled? Yes of course.

Is it easy to accurately aim while doing that? Not at all.

So while a player might mitigate the sensitive elevator and heavy ailerons, they would still have to constantly control the aircraft motion. This is especially noticeable in accelerated flight or turn.

A reworking of the stick settings would eliminate this and allow the stability and control features of each aircraft to be more accurately modeled. Just go the a dead zone to 100% curve. That way, somebody could flatten out response around the dead zone but the slope of the curve increases as we get closer to full deflection. One could "pick their poison" so to speak but could not eliminate modeled behaviors.

The developers can also model the airframe limits. Currently, you cannot bend or break the airframe and the accelerated stall is non-existent.

The aircraft's reaction to gun recoil could also be modeled. As an unstable platform, the arm is shorter which means less resistance to motion.

The penalties on turn performance for riding the buffet or pulling into it. Completely independent of stick settings.

The idea is to get player in the mindset of a WWII pilot flying the modeled type of aircraft. That is IL2 Cliffs of Dover main strength IMHO and why I got the game.

We have all seen the RAE concerns about pilot's not pushing the aircraft to the limits because of their fear of the flying qualities. That is fear is justified by the measured results of the NACA. Yes, the airplane had great stall characteristics too. The caveat being what is emphasized in the Operating Notes, correct and immediate application of the controls. The right control movements at the right time. If the pilot did not immediately make the correct inputs, the aircraft would spin after flicking out of the turn on a reciprocal course.

If he made the correct inputs, the aircraft recovered and even maintained a relatively high degree of aileron control just above stall. The NACA mentions that because it is unusual. Touching the ailerons on a stalled wing in general is not a good idea. Cessna drivers do it all the time, though, LOL. In most aircraft the rudder is the only effective control immediately post stall.

It does leave the aircraft with its tail toward the enemy and the choice of continuing with a slight altitude loss in slow flight or diving for more airspeed.

So the penalties for the buffet and the accelerated stall characteristics can also easily be modeled.

To mitigate the fact players could dial out the most important characteristic that made an early mark Spitfire unique, the sensitive elevator and heavy ailerons. Since players are going to cheat, developers can too. I did this in Warbirds and it worked great when I did the Bf-109 and Spitfire models.
If an accelerated stall is reached, the aircraft spins. This keeps players in the mindset to stay off the stall point.

So it eliminates a nice feature of the Spitfires stall characteristic but realistically, Spitfire pilots did not seek the stall except as rare method to escape an unwanted combat. If the players are going to cheat, let the developers do so as well.

Now I understand that Figure 15 does hint at what you are getting at yet I see no such problem in figures 16, 17 & 18 of the same report and you don't seem to analyse them in your argument? Odd as they are essentially they are same test as figure 15 but in the opposite direction (16) and at higher speeds (17 & 18). Looks like a relatively constant G was held throughout by the pilot. Or am I missing something?

The report alludes to "careful" flying. Does that mean "not careful" flying in the other charts.

Yet it does not say that is was dangerous flying quality. It just did not meet the Requirements laid out in report 755. It was not built to that standard so should it surprise that it doesn't meet all of them?

Now on the Spit V they did use a inertia weight to combat over sensitive elevators on that Mark. Why did they not demand a retro fit of inertia weights to the MK I & II that would have been in the OTU squadrons at the time if it was such a problem?

I think of the Spit like a Porsche 911, a great car which is a delight to drift around corners, but you really have to work to hold the thin line before it bites you in the a**.

With a regular driver it is still a great sportscar and outperforms many of its competitors, but to have the edge you have to be a pro.

The same will be with the 109, where the pilot has the opposite problem of too high stick forces at high speeds.

Each needs his own tactic to use the quirks of ones plane for optimum efficiency.

This is very true

Slight correction on the Mk V - the reason the inertia weights were added was to help overcome a problem with poor cg loading at a squadron level, plus the added weight of new equipment not used in Spitfire Is and IIs (see Quill http://forum.1cpublishing.eu/showpos...&postcount=781 )

Good questions.

No, these where done with "careful flying". If you read the report, they were done with force measurement equipment hooked to the controls.

The pilot could move the stick but when he let go, the equipment held it fast so the forces could be measured.

He could move the stick if needed to keep the accelerations within safe limits.

So, the controls in the test are done with about as careful flying as you can get. Most Spitfire pilot did not have a force gauge holding their controls fixed.

It is dangerous under conditions the pilot can overload the airframe. That is why you see the incidence of in-flight structural failure's and the warnings in the Operating Notes.

It is dangerous when you need to shoot accurately and it is dangerous when you need to make an abrupt maneuver to avoid and enemy attack.

Yes, it can be controlled by the pilot and mitigated by his skill level. It requires such input.

You have hit upon the entire reason the Air Ministry did not have stability and control standards outside of pilot opinion.

The British were major pioneers in stability and control in the beginning but kind of floundered after World War I.

Again, the RAE may have blamed it on that but they were also behind in Stability and Control research. The NPL pretty much stagnated until the efforts of Gates and Lyons came to fruition post war moving AWAY from the conclusion stability and control could not be defined without pilot input.

http://img651.imageshack.us/img651/6...lstandards.jpg



The opinion of the NACA was much different and their test aircraft was NOT overloaded and at a normal CG.

http://img856.imageshack.us/img856/8...tudinalsta.jpg

Notice how the problem was 'tails' breaking and not 'wings' bending that were the main case for structural failure, of course Crumpps highlight there mentions nothing about early Spits and in fact probably is refering to the MkV.

Spitfire pilots didn't seem to have that much trouble shooting down German a/c during the BoB despite being out numbered in the air over south-east England.

There are such warnings for American a/c.

I know it was later modified with an inertial elevator. They did something to correct it, you can bet.

The fact remains, the RAE skirted around the problem because they had no real estabilished foundation for what to do with longitudinal instability.

Especially when the pilot's opinion ran contrary.

It is really interesting if you like the history of technological development. There was a guy in England who laid down all the math just before World War I. It was in center of pressure and metacenter so his mechanics were not completely correct but all his principles were as well as the use of polynomial co-efficients to describe motion. Professor GH Bryan's really cracked the nut on stability and control.

Some of his conclusion's are used today. The problem was when he tried to explain it, it was so complicated that most engineer's eye glazed over, mouths came open, and the drooling begain. Then, some pilot would hop in the same plane his big complicated set of equations had predicted was unstable and fly off in it.

You can control an airplane that is unstable, especially the long period oscillation the NPL became focused on. The 1903 Wright Flyer was so unstable, the techique used to land it was to fly close to the ground at low velocity and let the skids touch on the downward oscillation.

You could not estabilish a stabilized approach that is common in todays airplanes.

They flew extremely unstable aircraft all the time in the early days of aviation. The velocity and forces were low enough that stability and control just was not that important.

http://www.hq.nasa.gov/pao/History/SP-468/ch2-2.htm

That all changed with the advent in the powerful monoplane fighters of World War II. The speed and forces involved pushed the science of stability and control to the forefront.

Really, by god....don't model it, we might see "porked" american fighters....

:rolleyes:

Quick, withdraw the facts about the Spitfire!!! Run!! There will be revolution!!

:eek:

Documented evidence for this, please.

Alex Henshaw's comments make interesting reading on the Spitfire as a gun platform and on its elevators:

http://i91.photobucket.com/albums/k3...-page-003a.jpg

Note Henshaw comments that the Spitfire's elevators were light cf those of the Tiger Moth or Magister on which pilots trained....

Now, a comment on the Pilot's Notes used by Crumpp which can be found here: http://www.scribd.com/doc/4598146/Pi...lin-XII-Engine - this is a most unusual set of PNs, even for a reproduction. For one thing these have detailed information and comments on combat skills and aerobatics, which few pilot's notes normally had.

http://i91.photobucket.com/albums/k3...pitIIcover.jpg
http://i91.photobucket.com/albums/k3...ombatnotes.jpg
http://i91.photobucket.com/albums/k3...tIIcombat2.jpg
http://i91.photobucket.com/albums/k3...erobatics1.jpg

These were not the standard PNs issued to pilots on frontline units - those ones invariably had blue covers: the notes that were issued to trainee pilots at OTUs had orange covers and these notes were conservative in their approach to ensure hotdog young pilots, who had gotten used to heavier elevators on the Tiger Moths etc, were made fully aware of the lighter Spitfire controls.

Wrong, once again, as Jeffrey Quill made quite clear he witnessed what had happened - unless Crumpp can show that he knows better about what happened in 1942 than Quill...nothing but speculation.

As for Crumpp's continued assertions about how hapless the Brits were when it came to defining control and stability? The first page shown by Crumpp is talking about 1910-1912: it has no relationship to the 1930s and the Spitfire whatsoever!
This is page 5 from the Von Karman Lecture 1970:
http://i91.photobucket.com/albums/k3...e-page-005.jpg

Page 6 - the one posted by Crumpp
http://i91.photobucket.com/albums/k3...e-page-006.jpg

What has what happened in1910-1912 got to do with ANYTHING in this thread??? :confused:

CF: 1937 ARC report

http://i91.photobucket.com/albums/k3...7-page-001.jpg
http://i91.photobucket.com/albums/k3...-page-011a.jpg


CF: the 1939-48 ARC report
http://i91.photobucket.com/albums/k3...8-page-001.jpg
http://i91.photobucket.com/albums/k3...-page-005a.jpg
http://i91.photobucket.com/albums/k3...-page-006a.jpg

Do you read what you are highlighting or posting?

The Operating Notes almost verbatium repeat the exact same warning for the Spitfire Mk II AS THE MK I.

In fact, you have saved me the trouble of posting them.


Bryan's theories were developed before WWI but the attitude that pilot's determine flying qualities over the engineer persisited until after World War II.

It was not until AFTER World War II that the ARC developed a standard that all designs had to meet.

That is a fact.

The article you posted points this out.

First it concludes that the Aeronautical Research Council made the mistake of regulating stability and control engineering to an academic exercise leaving the practical to the opinion of pilots. Exact same thing the AAIA article I posted relates.

Then, the ARC concludes that a foundation was laid during the war for estabilishing a defined set of standards for stability and control.

http://img88.imageshack.us/img88/143...948page001.jpg

http://img189.imageshack.us/img189/8...48page005a.jpg

http://img440.imageshack.us/img440/8...48page006a.jpg

http://img217.imageshack.us/img217/8...fastandard.jpg

MMM, It is in the thread already. Read the stability characteristics of the Spitfire. You seem to not understand it or ignore it. Instead, you place more value on anecdotes which are impossible to quantify.

You also quote the lone voice in the wilderness from Alex Henshaw who never fired a shot in anger.

Let's get some from guys who flew both in combat:

This is the reality. The Longitudinal stability is a defining characteristic of the early Mark Spitfires. It is part of what makes the airplane unique and gives it personality.

http://img521.imageshack.us/img521/3...vsspitfire.jpg

http://img607.imageshack.us/img607/4...sspitfire2.jpg

Wow, check that out. The first pilot could not make a kill because when he touched the firing button, the nose pitched down due to the longitudinal instability.

The second pilot disliked doing aerobatics. He felt the ailerons where too stiff, the elevator to sensative, nose too long, and the cockpit too cramped.

You can google "Hurricane vs Spitfire gun platform" yourself and not the results. A defining characteristic of the early mark Spitfire is it's twitchiness as a gun platform. Yes, it too, is a function of the longitudinal instability.


The Spitfire was not a an airplane for the inexperienced or average pilot. It was a pilot's aircraft and demanded skill. For that skill, it rewarded those who mastered it with exceptional performance. That breeds affection.


Good analogy.

IMHO, the generalize the three fighters of the BoB....

The Spitfire is sportscar. The Hurricane a workings man's tool.

The Bf-109 is a shooting platform for a machinegun with an airplane built around it.

It does not require my opinion.

This is all measured and defined by the NACA, the same characteristics appear as warning in the Operating Notes, and are repeated in a flight testing as well as anecdotal evidence.

My suggestion would be to go school and take some aerodynamics classes.

Sorry but have u read these articles?? These are first impression of a Pilot flying a new and different type of Plane. Of course it reacts totally "unnormal" as what he imagines and knew from the Hurricane.

And just because the Spit reacts quickly on a pitch input doesnt mean that she is a unstable gun platform in my opinion.

Thats why u practise as a Pilot to understand the plane and get used to it.

And thats why u have planes for "rookies" and "experts". But u can't compare or mess this with data because every Pilot has his own flying Skill and learning curve.


wikipedia: "Longitudinal stability

The longitudinal stability of an aircraft refers to the aircraft's stability in the pitching plane - the plane which describes the position of the aircraft's nose in relation to its tail and the horizon.[1] (Other stability modes are directional stability and lateral stability.)

If an aircraft is longitudinally stable, a small increase in angle of attack will cause the pitching moment on the aircraft to change so that the angle of attack decreases. Similarly, a small decrease in angle of attack will cause the pitching moment to change so that the angle of attack increases.[1]"

Crumpp's story has now changed from a blanket statement that the British had no standards on control and stability to one saying that the British "moved away from the conclusion stability and control could not be defined without pilot input."

The Americans no longer needed pilots because their know-all engineers could design perfect aircraft without any input from pilots whatsoever. Just pop an engineer into the cockpit...leave the pilots twiddling thumbs on the ground.

So why, pray tell was lack of pilot input such a wonderful development? Because it was purely subjective! Ignorant pilots could not quantify that seat of the pants feeling, nor could they accurately report on what had happened because they were too busy flying and controlling the plane.

Which is exactly what the British were saying in 1937
http://i91.photobucket.com/albums/k3...-page-011a.jpg

and 1938
http://i91.photobucket.com/albums/k3...harpe/009a.jpg


Meaning that Crumpp has flown a Spitfire and fired its guns in anger - albeit in a flight sim - and knows more on the subject than Henshaw, who had simply spoken to Spitfire pilots about its qualities as a gun-platform. Then he goes into anecdotes which cannot be quantified and happen to be from pilots who had gotten used to the Hurricane and showed a certain amount of prejudice

http://img521.imageshack.us/img521/3...vsspitfire.jpg

http://img607.imageshack.us/img607/4...sspitfire2.jpg

As well as this Crumpp also claims that he knows better than Jeffrey Quill why Spitfire Vs were fitted with inertia weights:

and the reply...

http://i91.photobucket.com/albums/k3...rpe/Quill3.jpg
http://i91.photobucket.com/albums/k3...rpe/Quill4.jpg
http://i91.photobucket.com/albums/k3...rpe/Quill5.jpg

I was struck by the observation the British made that in the past they had relied too much on a thoretical view, which is exactly what Crumpp has, a theoretical view.

Crumpp has been adivsed of the late 1980's approach to this topic ie that its a blend of theory, handling and an awareness of the mission being undertaken. These more modern standards he has ignored

He keeps saying that the Spitfore broke up easily in a spin which is why it was banned in the Pilots Notes. Unfortunately he has yet to produce one example of such a loss. I should add that I expect there to be a few but the fact that Crumpp has failed to produce one says a lot

Crumpp also says that the Spitfire was prone to structural failure due to stability issues, but so far he has yet to produce one example. Again I should add that I expect there to be a few but the fact that Crumpp has failed to produce one says a lot

He has also made reference to piles of bent wings awaiting repair in the BOB but has yet to find one example

Crumpp has failed to produce any evidence that the level of instability was dangerous. Much is made of the fact that the pilots notes warn of this, rightly, but no comment that the notes worked as proven by the lack of crashes.
No comment has been made has been made that Pilots notes err on the side of caution, we only have a catastrophic reading.

There clearly was a problem with the Mk Vb and bob weights were introduced on operational aircraft until a better solution was found. The evidence is that this was caused by poor loading in the squadrons but it didn't matter the problem had to be solved and it was. Even her Crumpp insists that this was a problem from the start and bob weights were introduced into all early versions of the spitfire. UNfortunately no evidence has been put forward to support this view. INdeed what has been posted is clear that the Mk I and II were not impacted by the problem.

Much is made of the fact that the Spit wasn't a good gun platform, something that is hardly new and that some pilots were afraid to fly it. A contridiction if ever there was one. If the plane was so unstable why did the pilots love it? However he doesn't mentin that in the same document that the pilots loved the aircraft.
The British were so far behind the times apparently re stability and to prove this he uses a pre WW1 document, a time when they didn't know how to deal with a spin?

Crumpp makes much use of this type of statement

It does not require my opinion.
This is all measured and defined by the NACA, the same characteristics appear as warning in the Operating Notes, and are repeated in a flight testing as well as anecdotal evidence.
My suggestion would be to go school and take some aerodynamics classes.

A few observations on this
a)NACA were using a Mk Va, an old aircraft, known to be the one most suseptable to stability problems, one without a crew up to date with the latest rules and regs in the UK. They did their mesurements but even here, they never said that it was a danger, they did say it didn't meet their normal standards but they didn't say it was a danger. If they had thought it was that bad I am confident they would have said so as Americans are not known for holding back unpleasent truths.
b) No one denies that the Spit wasn't perfect which is why the Pilots notes say what they say, but I repeat they always are cautious.
c) Comments about flght testing. I have asked Crumpp often to supply any flight test from any nation (including Germany) who found this aircraft dangerous this question is still outstanding.. I can only conclude that he has no evidence and by saying this he is exagerating his case
d) Going to classes on aerodynamics. Crumpp may or may not have had some training in aerodynamcis, I don't know.
I do know he offerred to debate longitudinal instability by a number of standards. Unfortunately one of these was to do with roll rates for differing types of aircraft and one was to do with the Rules and regulations about ordering spare parts to stop counterfit parts entering aircraft. Again I believe he was trying to exagerate the strength of his position

Above all of this is the lack of accidents. All the issues he talks about are serious safety issues but we have a serious lack of any incidents.

I bring you back to the first point in this posting.
I was struck by the observation the British made that in the past they had relied too much on a thoretical view, which is exactly what Crumpp has, a theoretical view.
Crumpp by not considering the views and experiences of those who flew the aircraft is relying almost totally on a theoretical approach. The standards of the late 1980's emphasise the importance of mixing theory, hands on experience and the task the plane was designed for, by ignoring this he is making the same mistake the British made in the 1920's. The last ones that I used are MIL-STD-1797a but these may have been modified

There might be hundreds of Spitfires being lost over sea or behind enemy lines because of mishandling in stress situations, all disregarded because being accorded to enemy action.
Nobody knows that for sure.
The only data we have is a per se incomplete list of researched accidents.

I heard that some Spitfires were pink, maybe they should all be pink?

I have a set of Orange covered Spitfire MKIIA notes (Paper reprint) that bear little resemblance to the ones in SCRIBD.

As was discussed in this "Thread that never ends" in the set I have Spinning was permitted if pilots were authorised by the CO or CFI at the OTU level. The Scribd ones say deliberate spinning was prohibited.

So two references with opposed statements.

Originally Posted by Crumpp http://forum.1cpublishing.eu/images/...s/viewpost.gif
The aircraft's reaction to gun recoil could also be modeled. As an unstable platform, the arm is shorter which means less resistance to motion.


Cough If you actually flew the sim you would see it is modelled !

And there's the rub. ;)

Reading the bibliography to the text of a lecture delivered in 1970 and referred to by Crumpp as definitive proof of Britain's lack of control and stability standards: Development of Airplane Safety and Control Courtland D. Perkins
(http://forum.1cpublishing.eu/showpos...&postcount=837)

http://i91.photobucket.com/albums/k3...e-page-012.jpg

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

The references stop at an ARC paper PUBLISHED IN 1913 - NOT ONCE does the author refer to the ARC papers from 1937 through to 1939-48, nor does he have any references concerning British research during the war years, instead concentrating almost exclusively on American aeronautical research - he had no idea of what sort of development the British had put in after 1913: this one is busted.

I wonder what we would see if we looked at the bibliograpies of most of the books referenced by Crumpp - how many of them concentrate on American research, ignoring Britain?

NzTyphoon,
Why do you keep confusing individual research with an established standard for all????

You obviously cannot differentiate between the two.

It is a fact, there was not an established standard for stability and control in the United Kingdom during WWII.

Glider,

You have constructed so many fantasies and misconception about this I don't even know where to begin.

Read the report. It is measured and defined.

What do you have an issue with?

You really don't need much to understand it. You can read the plain English text for the warnings in the Operating Notes, right??

You seem to deny they exist and keep accusing me of making something up?

As for spin recovery, is it so difficult to understand recovery ends in a dive?

Read the Operating Note warnings!!!

http://www.aopa.org/asf/publications...tall_spin.html

Go out and do some spins in the an airplane, please!!

Make sure it is not approved to spin and leave the chutes on the ground. <joking>

:grin:

Why don't you post the ARC standards.

Here is the NACA standards adopted during WWII. The USAAF and USN used these as the basis to define their own standards by 1944.

Until those individual service standards were adopted, they used the NACA's.

http://www.nasa.gov/centers/langley/...s/WWII_prt.htm

End the speculation and just post the standards during the war for the ARC.

Thanks!!

:grin:

Here is the USAAF and USN standards adopted in 1944.

NzTyphoon will share the ARC standards with us shortly! :cool:

What is the date on your Operating Notes that reference the spinning permission thru special training?

Not special training just authorisation.

Issue Date July 1940 Revised Dec 1941 and Amended up to Al No 25K which was added according to the AL sign off sheet as Aug 1942.

Ok, that is after the inertial elevator was added to the design.

Inertial elevator ??

Are you referring to the bob weight in the pitch circuit or increased balance area on the elevator as fitted to MKV's ???

Can I ask for your analysis of figure 16 17 & 18 of the NACA report? It seems figure 15 was an anomaly when compared to the next 3 which where doing similar test?

Someone (whiny?) earlier quoted a report from the morgan book on the Spitfire about inertia weights being not required for the MK I & II as long as the rear oxygen bottle was removed. Would be interesting to see the full report.

IvanK,
The early version of the Mk II manual, which Crumpp is quoting, is for the planes with Rotol props only before the CoG limits were revised. Later the planes (any early Spitfire) with the Rotol props got tighter aft limits, 7.5" aft datum with atandard elevator and without bob weight, while the planes with the DeHavilland prop only got limitations for extended CoG limits, bob weigh required if CoG 7.9" aft datum. In other words bob weigh was not required for the planes with DeHavilland propeller.

The later manual you are quoting is for the Mk IIs with both propellers, Rotol and DeHavilland, after the CoG limits were revised, hence no warnings about the elevator control reversal. Note that longitudal instability and elevator control reversal are related to each other and CoG but not the same thing.

As pointed out earlier with documentation and calculations, the NACA tested Spitfire had the CoG at 7.8" aft CoG and Rotol prop, in other words the CoG was behind the limits and the results are not representative for all the early Spitfires nor all CoG positions.

I think the Oxy bottle statement is discussed on P143 of the Morgan Shacklady book.

Here is the bit.

http://i40.photobucket.com/albums/e2.../Spitbobwt.jpg

The 30 June meeting discussing the general fitting of bob weights refers only to the MKV.

The Bob weight was initially trailed on the one off Spit MKIII. It was tested also on a single MKII airframe P7280 that features in a lot of the RAE tests.
So unless more evidence is provided there is nothing to confirm that bob weights were actually fitted to operational MKII's

Spin trials by RAE on the MKII and MKI (as posted earlier in this thread) generally considered spin characteristics as normal ... no real drama.

Here they are again !
http://i40.photobucket.com/albums/e215/zulu64/X1.jpg

http://i40.photobucket.com/albums/e2...4/recovery.jpg
http://i40.photobucket.com/albums/e215/zulu64/X2.jpg

http://i40.photobucket.com/albums/e2...I_Spinning.jpg



Thanks Mig-3U more evidence that operational Spit II's wernt fitted with Bob weights.

Thanks Ivan.
This mumbo-jumbo is an example of Crumpp's intellectual dishonesty coming to the fore - the document he has cited in an attempt to bolster his "case" has nothing to do with the point he is trying to prove. "The Development of Airplane Stability and Control Technology" has done no research into British aeronautical development after 1913 and, as such, it has nothing whatsoever to do with the Spitfire's longitudinal stability. Crumpp has not bothered evaluating the sources used by a publication before citing it as "evidence" - this is one of the basics of historical research.

http://i91.photobucket.com/albums/k3...e-page-012.jpg

So, while NACA had formulated a set of specifications they had yet to be properly standardised because as late as October 1944 NACA was still discussing how to implement the specifications with representatives of the Army, Navy and aircraft manufacturers. This does not say anything about the specifications being adopted in 1944 - just being discussed pending adoption.

Now, Crumpp insists on an Aeronautical Research Committee report confirming British standards in control and stability; what Crumpp doesn't seem to realise is that the ARC is an advisory body which works to distribute information and reports to the likes of the National Physical Laboratories, RAE and manufacturers (para 2 Policy of the Committee). Unlike NACA it does not do its own research: unlike NACA papers on stability and control can only be accessed via archives such as this entry, NA Kew.

http://i91.photobucket.com/albums/k3...8-page-003.jpg

Reports tabled in ARC report 1939:
http://i91.photobucket.com/albums/k3...page-004-1.jpg

As it is bug tracker #415 won't be gaining any traction at any time soon, so there isn't much future in pursuing this thread any further.

So.....can we have that 109 thread now?

It is very simple NzTyphoon.

Post the standards developed by the ARC.
Thanks!!

Wow,

Let's not be obtuse. I never said there was no research in stability and control.

I said they stagnated into an attitude that flying qualities was an academic exercise and that the pilot's opinion was what was practical.

Big difference from what you are claiming.

The NACA took a different route. They developed techniques as well as equipment to measure and quantify behaviors. Part of that system was training test pilots and developing manuevers to define behaviors within flying qualities. In fact, it was Cooper's experience as a test pilot at the NACA that led to the development of the Cooper-Harper Rating scale.

http://www.google.com/url?sa=t&rct=j...zIxnwH4SfCszng


No, I are referring to the one fitted to Spitfire Mk I's to correct the longitudinal instability.

Never happened, only the MkV was 'ever' fitted with a bob weight.

God forbid that when designing something to be operated by a human you would ever actually ask those humans for any advice.

I wonder why on some adverts the slogan 'designed by XXX for XXX' is used, it's almost like the oppinion of the end user counts for something.

Having wasted hours trying to get Crumpp to provide some documentary evidence to prove his cock-eyed theories on 100 octane I am not interested in complying with these demands.
Let me complete that for Crumpp:

The only one being obtuse is Crumpp, who tried to use an irrelevant paper to bolster his "case". Anyway I'm done wasting time on Crumpp flogging his dead horse and pointless bug tracker - he can waste as much time as he likes here.

Except that spins are prohibited.

They never changed the Operating Notes. It is not because they are lazy. Nor is it because they want to "reduce risk" by not training their fighter pilots in spin/upset/unusual attitudes.

Spin training, upset, and unusual attitude training is essential to a fighter pilots core mission.

I said from the begining, any engineer can look at a design sitting on the tarmac and know if the airplane has a high chance of normal spin recovery assuming the CG is normal or forward. The Spitfire has all the characteristics required to spin normally.

Therefore, the only real issue is the longitudinal instability.

The never changed it because a high speed dive is generally the result of spin recovery and a Spitfire pilot could break the airplane rather easily.

http://img842.imageshack.us/img842/3...dwingsfail.jpg

I was just curious if spin trials were done after the longitudinal instability was fixed in the Spitfire Mk I's.

The approval to train after being checked out by a Squadron Commander or CFI at an OTU certainly did not appear until the airworthiness directive fixed the instability.

http://img513.imageshack.us/img513/6...htelevator.jpg

You mean like the fact it is not the specified fuel in the portion of the Operating Notes entitled "Notes on a Merlin Engine" is a strong indicator the fuel is still undergoing service testing?

I never disputed the fuels use, just the silly notion it was the only fuel available and the adopted service fuel.

Who would ever suggest they were still undergoing 100 Octane fuel testing in August of 1940 simply on the basis the facts do not align?

http://img20.imageshack.us/img20/6282/83062903.jpg

100 Octane is completely off topic. Start your own thread if you want to debate it.

Honestly I always thought a high speed dive is the typically the result of a prolonged dive. Is diving also prohibited?

NzTyphoon,

It is not my theory nor is that one report the basis of the conclusion the United Kingdom aviation authority did not have stabilit and control standards.

Simply post the ARC standards used during the war. They will be written in a simliar fashion to EVERY other stability and control standard in the world.

They will define the acceptable qualities in an airplane.

Just like the NACA did!!

Here is the link to the UK ARC reports:

http://aerade.cranfield.ac.uk/listarcrm.php

What does a deliberate dive have to do with a spin?

In spin recovery with longitudinal instability, if the airplane is below Va, the risk of secondary stall is greatly increased.

Above Va, the risk of airframe destruction is greatly increased.

Understand?

The pull up during spin recovery above Va has increased risk of airframe destruction.
The pull up during dive recovery above Va has increased risk of airframe destruction as well.

Why is one prohibited and the other not?

Probably because a controled dive with a defined level out altitude is different from a spin with a uncontroled loss of altitude and therefore the possible increased urgency to level out before hitting the ground.

See robtek's post, 41 Banks.

Exactly, in a normal dive, it would be very unusual for the pilot to be "behind the airplane". In an accidental spin, it is very likely the pilot will be "behind the airplane".

Goes back to aviation axiom, "Never Let an Airplane take you someplace your brain did not get to at least 5 minutes before."

Right BTB,

If you read the spin recovery procedures in the Operating Notes, it instructs the pilot to make a prolonged dive.

With the longitudinal instability, the aircraft would require more more velocity to buffer against over controlling the recovery and inducing a secondary stall.

In otherwords, the low stick forces and large elevator changes for very small stick inputs make the aircraft vulnerable to secondary stalling in a normal spin recovery sequence.

The high dive speed required to recover from a spin also make the aircraft vulnerable to exceeding the airframe limits by overcontrolling.

I would not be surprised to discover the Spitfire Mk I was cleared to spin after being fitted with an inertial elevator to correct the longitudinal instability.

Indeed, spinning is one of the most dangerous man oeuvres. Combined with the fact that there is little to no benefit from a deliberate spin it's the simplest solution to prohibit it.

Btw I don't get why topic has so many pages. Just read the Pilot's Notes, it's all there:

- exceptional/remarkable light elevator response even at high speed, which is a good thing and a bad thing (risk of high speed stall and blackout/break up the aircraft if pilot is not carefully)
- instability in turns (elevator becomes lighter in turn)
- stall warning/buffeting/buzz (best turn rate is achieved slightly before buffeting)

Now let's look at the current FM and find out if this is represented.

I see you're still using the MK V as your data source for a Mk I/II.

Lmao.

Anyway, this thread is supposed to be about early mark spitfires.
Can I please see some data for a MK I or II?

I'm bored by all this Mk V stuff. It's irrelevant to CLoD.

It doesn't matter what was prohibited and what wasn't. For every single time Crumpp has said that the pilot's notes forbid something I have been able to find a combat report or pilot account where the same manouvers were done deliberately by a pilot. Brian lane deliberately entered spins, deliberately stalled etc etc.

Here we go again with the pilots notes red herring..

Pilots notes are just someone's opinion. They are not proof that prohibited manouvers were never performed. They are just a set of reccomendations. Good pilot's overcame their machines limitations on both sides.

Being behind the airplane is a requirement to get in an accidental spin in the first place.

FACEPALM!!!!

From the first post in this thread AND the bugtracker....

Noted Winny...

In your opinion the Operating Notes are just for sissy's.

If you ever fly an airplane, be sure to tell that to the Aviation Authority, your instructor, and your insurance company.

Put it on your resume too. Maybe NASA or ESA will hire you as a test pilot.

Probably not, but you can dream.

Yawn, how's this relevant to CLoD?

You've made your point, the elevators on the spits should be sensitive.... News flash.. In CLoD they already are.

So what would you do to the Spit in game? What would you change? Bearing in mind that stick forces are irrelevant? After god knows how many posts I've yet to hear anything from you about how the MK I or II in game is behaving incorrectly.

So, what is wrong with the current FM in CLoD?

Nice reply, attack the poster not the point... And don't put words into my mouth. Where did I say the notes were for cissys?

I didn't. I pointed out that I have pilots accounts of all of the prohibited moves you have mentioned being performed. So the pilot's notes bear no relation to what sometimes happened. Or are you going to tell me that these people who were there were lying?

Again. What changes need to be made to the MK I or II in the game?

Nice summarisation, that of course will be ignored by all who are looking for a dispute instead a solution.

Look Crumpp, they said: " Allow the airplane to gather a speed of well over 150 mph, (thats not a high speed dive), before gradually easing out... " to reach this spead, thats your prolonged dive.
Recover the spinning, " there is no difficulty in recovering, provided the standard method is correclty used, i.e , full opposite rudder (maintained unter the spin stops) and stick slowly forward when recovery begins.... . " Thats what they (the Pilots) have learned since Flight school.

For all that you are trying to prove there exist advises.



Please do me a favour and make some guestflights in a Glider to understand this practically or in an aerobatic plane. Or look into some youtube videos to get an imagine how this looks like.
;D

EDit: just a few links
http://www.youtube.com/watch?v=Rne-k...eature=related

http://www.youtube.com/watch?v=ZU14F...Vdk&playnext=1

http://www.youtube.com/watch?v=-8Ilp...eature=related

BTB, to be so condescending on such thin ice, ts ts ts.

150 mph, in a vertikal dive, with a GRADUALLY recovery, surely you'll reach a pretty high velocity before leveling out, accelerating all the time.

That is not a > 500 kg glider but a 3 ton machine with a not that much larger front surface.

http://www.youtube.com/watch?v=PBes98c8RSA

http://www.youtube.com/watch?v=c4Xbk...eature=related

http://www.youtube.com/watch?v=Kn3Rf...feature=relmfu

http://www.youtube.com/watch?v=_J9N8...eature=related

Mass doesn't matter in vertical acceleration*. The speed doesn't instantly increase from below 150mph (second stall) to above x mph (aircraft breakup).

Again I don't get the discussion. All source state that spin recovery is pretty standard for Spitfire. The only "problem" is the light elevator/relative instability, which makes precise control more difficult than in other aircraft, but this is only a issue if the pilot is not used to the aircraft.
It's like driving a car with a sensitive clutch. You must be careful on the first day, but after a week it won't make a difference and you make use of the benefits.

That's only true in a vacuum. You have to account for density (among other things) when in the atmosphere.

The thing is that if a pilot has a stall a bit closer to the ground and has to recover under stress, as the ground is rising to meet him, it takes nerves of steel to first let the speed build up to 150 mph in a vertical dive and then to gradually recover from the dive.

In the Spitfire it should be possible to overstress the plane if not done correctly as there is only about 2lbs per g stick force needed, where in other planes the pilot may not have the power to recover soon enough or to overstress the airframe.

These tests were on the 100 octane fuel produced in the UK as a back up in case the supplies from the USA were insufficient

As probably 90% of Mk I and Mk II combats were over the UK I doubt that hundreds were lost behind enemy lines or over the sea. So the comment about a lack of examples is a valid one.

One has been identified in volved in a spin. Crumpps comment was typical The never changed it because a high speed dive is generally the result of spin recovery and a Spitfire pilot could break the airplane rather easilyThe fact that this example was in a high speed dive from low cloud, then did a violent pull up presumably to avoid hitting the ground, suffered a high speed stall, then spun and then had a wing failure tells me that it was far from easy to break a Spitfire wing. It was very difficult.

Edit - I should add that to say that a high speed dive is generally the result of a spin recovery is rubbish, any pilot with spin experience would know that. In combat a high speed dive is normally the result of combat, trying to evade or bounce an enemy aircraft. Spinning is slow speed activity and recovering doesn't take long you have to wait until you have sufficient speed. Its the wait that is often the more dangerous time as if you try to pull out with insufficient speed the plane tends to sink (often called mush)and can still hit the ground. Holding your nerve until speed has been reached with the ground coming up can be difficult for some pilots to learn.
If you are in a high speed spin you are normally dead whatever happens to the plane as you will be trapped by the G forces, unable to open the cockpit or get out

Exactly.

Your thrust vector adds to gravity, lift opposes drag <unless you dive a zero lift angle>

In short, away you go...

Like the one in my hanger???

That passenger is Col. Phil Lacey.

Col. Lacey flew P-40's, P-39's, and P51's with the 8th USAAF in World War II. In Korea he flew F-86's and Vietnam, Canberra bombers.

You don't what aerobatics is until you seen Phil take the stick, LOL. That old man can fly the paint off an airplane.

And yes, he reads and abides by the Operating Notes.....

Read the Operating Notes.....

BTW, you are not necessarily going to be vertical nor is certain you will enter a high speed dive.

There is a good possibility of that happening.

Wow, Lacey must be one of the oldest aerobatic pilots flying. At least 92, I'd guess, if he flew in WWII. Good for him!

Negative....if you are throttle closed then there is no thrust vector to add and a disking prop adds to drag, acceleration is 'not' infinite (see Captaindoggles post for a reason), in some aircraft a vertical dive will not even reach Vne.

since when did lift oppose drag?, lift opposes weight and thrust opposes drag, lift actually adds to drag because lift generates induced drag, if you fly at 'zero lift' then there is no induced drag.

Ohh!....a thorp t18....that's gotta be one of the ugliest mothers I've ever seen.

Is this supposed to convince us you know what you are talking about? because I'm even less convinced of that now.

A couple of obvious points,
1) if you are in a verticle dive then you are already going 150 + or will be in seconds so there is no delay
2) gradual will be smoothly for obvious reasons you dont want to exceed VNE or hit the ground, its a balance.

And we still don't have any accidents the acid test of fragility

PS please show me where is says that a high speed dive is generally the result of a spin recovery

"Spin training, upset, and unusual attitude training is essential to a fighter pilots core mission."

Actually Crumpp I think you might find that in EVERY current front line fighter deliberate spinning is prohibited !

Upset and unusual attitude training is in fact an essential requirement for every pilot, its mandated for Instrument ratings (in most countries). These terms were not used in WWII and are relatively recent terms.

As for spin training that should imo be mandatory as well ... sadly however it has been removed from the basic syllabus in a lot of countries.

As to this importance being placed on 150MPH before attempting recovery ... baloney !! that is a typical academic approach (as is this entire thread !) to the written word. Its in there to provide guidance to the lowest common denominator. As we all know after recovering from an unintentional spin, its simply a matter of getting your s... in one pile then smoothly recovering from the dive ... no magic just normal piloting to not depart the thing again. Its just like the 90degree nose down at low level scenario (you know the one you didn't want to be in in an aeroplane with stability issues) I suggested earlier .. you going to wait for 150 and risk hitting the ground or get on with your pilot stuff and "Fly the aeroplane" !

We should be able to crack the 1000post mark on this "never ending story" soon... just 100 posts to go.

By the way where is the in game test data in in Ver 1.08.18956 to support your bugtracker entry ?