Comparison of Fighter Roll Rates at 10kft

[Crump]

 

 

Spoken like a man who disregards all the DOCUMENTED PROOF proof that disagrees with his OPINION!

 

You keep trying to turn this into some sort of personal attack.  It is not.  

 

The same things I am doing to validate the data are the same things your developers will do.  If you want to suddenly increase the P-40's rollrate to be the agility king of world war II...it would make sense to be sure the data stacks up to qualified scrutiny.

 

 

Some food for though, since this thread is derailing the usual way: Phillips' CB was originally issued in August 1942. It's a summary of previous tests (i.e. nothing new was tested for issuing the report). The tests for the Hurricane and Spitfire were co-authored by Phillips, and are well known (debated to death in the net, usually with "particular" conclusions), issued as WR L-565 and L-334 respectively.   Since Phillips was also co-author of Confidential MR AAC, May 31 1941 Measurements of the Flying Qualities of a Curtiss P-40 Airplane (AC No. 39-160), there is a good chance that the data presented in this debated came from there. From the date of the report, flight test must have been done in early 1941 or late 1940, so there is a chance that the methodology was different than when the Hurricane, Spitfire or P-40F tests were done (and might explain the shape of the curves). So, the report in question should end the speculation (it's not available in the NASA ntrs server, BTW  ).

 

Interesting...thanks for posting.

[GOAT-ACEOFACES]

You keep trying to turn this into some sort of personal attack.  It is not.

Personal attack?

 

Hardly, I am simply pointing out that all the documented proof shows the NACA was well aware of the fact that rudder affects roll rates, therefore you asking us to believe the NACA was NOT aware of the fact is silly.

[GOAT-ACEOFACES]

 

Some food for though, since this thread is derailing the usual way: Phillips' CB was originally issued in August 1942.

Roger late 1942

 

It's a summary of previous tests (i.e. nothing new was tested for issuing the report). The tests for the Hurricane and Spitfire were co-authored by Phillips, and are well known (debated to death in the net, usually with "particular" conclusions), issued as WR L-565 and L-334 respectively.

That may be the case for the Spitfire and Hurricane.. But reading the NACA Confidential Bulletin, dated 16th november 1942, it begins by saying..

 

The Army Air Force has made available several pursuit-type airplanes for quantitative investigation of their flying and handling qualities.

Which would lead one to believe they were made available for the report in question.

 

Since Phillips was also co-author of Confidential MR AAC, May 31 1941 Measurements of the Flying Qualities of a Curtiss P-40 Airplane (AC No. 39-160), there is a good chance that the data presented in this debated came from there. From the date of the report, flight test must have been done in early 1941 or late 1940, so there is a chance that the methodology was different than when the Hurricane, Spitfire or P-40F tests were done (and might explain the shape of the curves).

A good chance..

 

But you agree, there is nothing in writing to prove that was the case..

 

Where as on the other hand, there is plenty of writing (read documented proof) that shows the NACA was well aware of the fact that rudder affects roll rates prior to 1940.

 

Therefore it is silly IMHO to think the NACA would preform a test to determine the effectiveness of ailerons and than allow the use of rudder.

 

So, the report in question should end the speculation

As should all reports..

 

But as noted above, plenty of documentation to show the NACA test procedures were in place prior to 1940, and that they were aware of the fact that rudder affects roll rates.

[JtD]

MMMMM,  Lets follow your logic..

 

A coefficient of lift is non- dimensional yet it changes from stall to cruise flight quite dramatically.....

Have it your way. Then the dimension is radians.

[Crump]

Of course...it is an angle

[Crump]

The early P-40 data appears to have been tested to a maximum of 230mph/30lb stick force. 30lb stick force were not reached at 230mph, only 19.5. If it was then extrapolated to 230*SQRT(30/19.5), it gets me to 285mph, which is exactly what NACA has as well in their chart, or 230*SQRT(50/19.5)=368mph, which matches the first posts chart. Just saying, feel free to ignore.

 

 

BTW,  if the ailerons are already at full control deflection....and they were in the data presented....

 

Adding more stick force input is not going to effect roll velocity...the controls are already at the stops.  Your pilot is just straining harder for nothing.

[Crump]

Doing a helix angle analysis....

 

The roll data actually agrees pretty good at low speeds.  The issue is at high speed.  

 

It is just a fact that P-40 aileron design could not benefit from increased aileron input due to the design of the control system.  Aileron input is pretty light in the P-40 and full deflection was achieved even with only 30 lbs input.  The cables simply stretched at 50 lbs of input and the design never achieves the characteristic crest as a result.

 

The P-40F curve represented on the NACA chart reflects the reality of a cable control system as found in the design.

 

The other curves agree at low speeds but that is about it.

[GOAT-ACEOFACES]

Crump, I can sum up in one simple statement why your argument is in error..

 

The ONLY way your argument would make sense is if the NACA did NOT realize the use of rudder would affect the roll rate.

 

Sorry, but that makes no sense!

 

Especially in light of all the documented proof that shows the NACA was well aware of the fact prior to 1940, if not earlier.

 

And that is why your argument has no merits

[Crump]

 

 

The ONLY way your argument would make sense is if the NACA did NOT realize the use of rudder would affect the roll rate.

 

No Aces, the NACA was well aware of lateral and yaw axis coupling.  

 

The issue is that not all pilots are aware of what a coordinated roll looks and feels like which is why the measurement of the rudder deflection is included. 

[Crump]

That may not have anything to do with it, either.  That was just a good explanation for the differences in your made up curve data and the NACA data.

 

The NACA did measure the P-40 aileron system investigating hinge coefficient theory in correlating 2D wind tunnel investigations to flight investigation.  The tools to make this in flight measurement did not exist until late in the war.  

 

Again, it is attributed to cable stretch.  In theory...the P-40 could roll very well at high speed.  In reality, it had a cable control system that stretched like every other control cable system ever designed and that means the design could not roll as well in the air as it could on paper.

 

 

[GOAT-ACEOFACES]

That was just a good explanation for the differences in your made up curve data and the NACA data.

Made up curve?

 

Oh, well that explains why your confused!

 

I did not make up the P-40 data! I got the data from the AHT book that I and others have posted, which is the same data from the NACA test you yourself provided earlier.

 

Both the P-40 and P-40F data in my graph is real world data

 

Hope that helps!

 

No Aces, the NACA was well aware of lateral and yaw axis coupling.  

 

The issue is that not all pilots are aware of what a coordinated roll looks and feels like which is why the measurement of the rudder deflection is included.

Actually that is not correct!

 

As I already showed in the NACA 715 document I provided, the NACA engineers and test pilots were well aware of the fact that rudder has an affect on roll rates prior to 1940.

 

Hope that helps!

[Crump]

 

 

I got the data from the AHT book

 

And what is source AHT used??

 

Again, according to the NACA measurements....unless the control system was redesigned to get rid of the cables...

 

No P-40 ever rolled that fast in the air.

 

 

 

NACA engineers and test pilots were well aware of the fact that rudder has an affect on roll rates prior to 1940.

 

 

Once again, you might benefit from some practical flying experience on this point.

 

Most pilots do not know what a coordinated roll looks and feels like in the air.  It is something that is very easy screw up and think it is right.

 

That is why the NACA concludes to measure everything.

 

[GOAT-ACEOFACES]

And what is source AHT used??

As I stated..

 

I got the data from the AHT book that I and others have posted, which is the same data from the NACA test you yourself provided earlier.

Hopefully it will sink in on your 2nd read!

 

Again, according to the NACA measurements....unless the control system was redesigned to get rid of the cables...

 

No P-40 ever rolled that fast in the air.

 

You might want to re-read the data you provided..

 

And note that no where does it say that!

 

All it does say..

 

It would be most desirable, both from the standpoint of effectiveness and stick forces, to eliminate the elasticity of this control system.

How you read that and conclude that no P-40 could ever roll that fast in the air is beyond me..

 

But does shed some light on your use of the word FACTS in place of a more accurate word like OPINION..

 

As the AHT graph 29 that VikS provided states..

 

The reason for the difference is un-known

 

Which I tend to agree with..

 

Or should I say, you have presented nothing here that would be considered scientific proof to the contrary.

 

Therefore, please don't be upset with me for taking the word of all those that worked on the AHT book over yours.

 

That is why the NACA concludes to measure everything.

 

General statements like that are great for talking about things in general..

 

But we are and have been well past the general point and have been for some time now..

 

As Typhoon showed you back on page 2..

 

 

Note the NACA procedures clearly state that recording of the the rudder deflection is optional.

 

In summary

 

The most telling part about all this is CrumpA was an advocate for all NACA data from late 1942 forward..

 

At least CrumpA was until I pointed out the P-40 roll rate data was from November 1942..

 

Than CrumpB showed up and disagreed with CrumpA and said no, late 1942 is not good enough..

 

Just saying..

Edited February 14, 2015 by ACEOFACES

[Crump]

 

 

How you read that and conclude that no P-40 could ever roll that fast in the air is beyond me..

 

I just did some roll performance math based on the data.  The exact same stuff the developers will do.

 

The NACA chart is correct and agrees with all flight tested data on the type.

 

 

 

 

Than CrumpB showed up and disagreed with CrumpA and said no, late 1942 is not good enough..

 

It is not Crump...

 

You are not getting the fact the NACA evolved as they gained experience and changed the rules.  It is a pretty simple concept and most people do learn from experience. 

[GOAT-ACEOFACES]

I just did some roll performance math based on the data.  The exact same stuff the developers will do.

 

The NACA chart is correct and agrees with all flight tested data on the type.

Well than you should consider writing a book called AHT is wrong..

 

Granted, based on the proof you provided thus far, I think it is safe to assume it will be listed under fiction!

[Crump]

 

 

Well than you should consider writing a book called AHT is wrong..

 

I am sure they printed the best sources that they thought.  Again, a little math will point the right way. 

[NZTyphoon]

Easy question to answer NzTyphoon.

 

The NACA found out that although pilots were reliable and truthful people.....measure everything because sometimes their perception and reality does not align.

 

The early standards did not require measurement.  They did leave it up to the pilot to meet the defined conditions of coordinated rolls.  

 

 

When all was said and done.....

 

Measuring the rudder position is extremely important.  It simply has too much influence on roll rate.

 

 

In effect Crump is saying, with the benefit of over 70 years of hindsight, that;

 

a) The pilot(s) flying the P-40 didn't know how to execute good rudder-fixed aileron rolls, thus the tests were mucked up because, to Crump's mind, the P-40 rolled too fast;

 

How does Crump know this? Was he sitting in the cockpit looking over the pilot's shoulder? Was Crump flying alongside the P-40, ensuring that the rolls were completed properly?

 

AND

 

b) NACA didn't measure the rudder deflection angles during the test to ensure that it stayed fixed;

 

Again, how does Crump know the rudder angles weren't measured, just to make sure that correct piloting technique was applied? Is Crump privy to additional information about how the tests were conducted, and what measurements were taken?

 

Just because the rudder deflection angles weren't shown in the document, doesn't mean that they weren't measured - what Crump constantly avoids acknowledging is that NACA in the 1940s didn't place a high priority on adding the figures to reports on aileron rolls.

 

It's only now, in 2015, that Crumpp insists that such figures should have been added, otherwise the reports are rendered useless.

 

Sorry NACA - you Failed Crump's Stringent Test Requirements - all those reports you spent so much time and effort writing were as useless then as they are now. Your test pilots poor flying techniques failed you! Be ashamed.

[GOAT-ACEOFACES]

I am sure they printed the best sources that they thought.

 

Agreed 100%

 

And, as noted, you have presented no proof to the contrary as to the validity of the P-40 data.

 

Again, a little math will point the right way.

 

Well, as we both know, your math leaves allot to be desired..

 

Remember the problem you had with the simple TE=PE+KE+ME equation?

 

So, someone saying they did the math, proves nothing..

 

Be it here or at work, I have the same approach, show me your work!

 

It is the best way to ensure no errors were made

Sorry NACA - you Failed Crump's Stringent Test Requirements - all those reports you spent so much time and effort writing were as useless then as they are now. Your test pilots poor flying techniques failed you! Be ashamed.

 

ROTFL!

[Crump]

Remember the problem you had with the simple TE=PE+KE+ME equation?

 

That was your issue and not mine....only you just did TE = PE + KE

 

You did not quite seem to grasp the mechanics that ME = TE + KE.

 

http://www.physicsclassroom.com/class/energy/Lesson-1/Mechanical-Energy

 

Isn't this the graph you were producing testing dive and zoom performance?

 

 

 

 

 

So, someone saying they did the math, proves nothing..

 

 

I agree, somebody who does the math wrong proves nothing.  However I am certain that your developers can do the same thing I can.

Edited February 14, 2015 by Crump

[GOAT-ACEOFACES]

That is the graph!

 

The first one!

 

Where as you took it and added the red arrows and notes about energy being destroyed! LOL!

 

And, thanks for confirming what I already suspect..

 

You still confused!

 

Another keeper!

PS I noticed you didn't post your work you claim as proof..

 

Not surprised in the least really! 

[GOAT-ACEOFACES]

In light of you still being confused about total energy..

 

Seven years later, and after you revived your degree, you still operating at a physics 101 level where all they do is consider the special cases, ie no friction. 

 

I think this may be a good time to try and teach you again, so, give me some time and Ill create a new post and than post the link here, since it is not related to the topic at hand..

 

Stay tuned!

 

Oh, and thanks for post those graphs, I no longer had a good copy of them! They will come in handy

[Crump]

 

 

Stay tuned!

 

Not really interested...

 

I got a degree and earned a 3.88 GPA.  Not my issue if you do not understand the stuff, Ace of Aces.

 

Here is an example problem from Basic Aerodynamics:

 

What would the altitude be when the aircraft reaches zero speed at the top of the climb before it starts a tailslide?

 

Either solve by knowing that total energy stays the same. This is a trading of kinetic energy for potential energy

             Total energy₁ = Total energy₂ 

            PE₁ + KE₁ = PE₂ + KE₂   

            16.48 x 10⁷ = PE₂ + KE₂   

            KE₂  = 0

            PE₂ =Wh = 16.48 x 10⁷ = 16.48 x 10⁷ ft-lb / 14000 lb = 11771 ft

 

Or solve using rectilinear motion equations only acceleration acting on the aircraft is from gravity

 

            s = (V² – V_o²) / 2a  = - (200 x 1.69)² / (2)(-32.2) =  -338² / -64.4 = 1774 ft

s = the altitude gained. so 1774 +10,000 = 11774 ft. within the error of significant digits these answers are the same.             

[GOAT-ACEOFACES]

Not really interested...

Your interest is not required

 

Not my issue if you do not understand the stuff, Ace of Aces.

Time will tell!

 

In the mean time..

 

You may want to look beyond the physics 100 level class examples that assume there is no friction..

 

Just saying!

[Crump]

Ok Aces.....

[MiloMorai]

I have known many engineers in my life. Some of them were great when it came to theory but utterly useless when it came to the practical application of theory.

 

The best were those that had both theory and practical and could explain what ever it was in simple terms that even a lay person not in their field would understand.

[=362nd_FS=Ikarus]

I have known many engineers in my life. Some of them were great when it came to theory but utterly useless when it came to the practical application of theory.

 

The best were those that had both theory and practical and could explain what ever it was in simple terms that even a lay person not in their field would understand.

Well spoken.

[=362nd_FS=Hiromachi]

 

Ask anyone what the most manoeuvrable and nimblest fighter of WWII was and at least 8 out of ten will say the Japanese Zero

 

and yet it has the worst roll rate by a fair margin

 

Cheers Dakpilot

 

I only wanted to add one point in regard to your discussion gentleman.

This NACA 868 report, coming from 1947, interestingly does not present any further details about the model of the Zero-sen nor we can see force limits. If someone would check the previous page - 165 - "Variation with indicated airspeed of helix angle pb/2V obtainable with 50 pound stick force." - it gives the following helix angle at 200 mph (pb/2V - 0.055) and at 250 mph (pb/2V - 0.04). As there were many types of Zeros, in fact starting with model 11 and ending with model 62 we would have 11 models to guess here. Some were similar, other different, but each would give a different results. 

 

In this case for A6M2 model 11 and model 21 the most detailed source are NACA reports from May 1943 - "Preliminary Measurments of Flying Qualities of the Japanese Mitsubishi 00 Pursuit Airplane" and "Results of Records Taken in Simulated Combat Maneuvers with Japanese Zero Airplane". They give detailed description of the ailerons, though it appears (as this was the famous Akutan Zero) that machine was not in finest condition as some angles of operation or other details do not match the Mitsubishi official documents, also it is recorded that this warbird with additional NACA instruments is a bit heavier than real machine.

 

But skipping that it is written, to note, rolls were performed without application of the rudder:

"A maximum value of pb/2V of 0.14 was attained with a total aileron deflection of 40 degrees in rolls to the right and left. This aileron deflection is believed to represent full travel of the control stick. The recorded aileron deflection is believed to be reduced from the maximum value of 48 degrees reached with no load in the system because of the deflection of the control linkages. (My note - Zeros used an elastic cords for controls surfaces, explanation for that can be found in Jiro Horikoshi book, "The eagles of the Mitsubishi") This value far exceeds that ordinarily attained by fighter-type airplanes. The unusual aileron power is attributed to the large size of the ailerons on this airplane. The pilot noted, however, that full aileron deflection could not be attained at speeds above 120 miles per hour, because of excessive control forces. (...)"

Following the same formula as in NACA 868, 120 IAS = 140 TAS, where roll rate would be 1.46 rad/s ( ~84 deg/s ). 

 

Given in the document data indicate that at 150 mph with left rolls Helix angle, pb/2V would be 0.10 and at 200 mph that would be 0.075. It is noted that the high speed roll rate is reduced which is consistent with combat reports written by the pilots which is of course true.

In general, the great wing area, high aspect ratio and high deflection angles all contribute to higher stick forces, but given equal forces, the Zero should out-roll, for example the Hellcat and just about any other fighter. However as we know, the stick forces were higher on Zeros. This was known to Mitsubishi and even before the outbreak of the war on the Pacific Horikoshi tried to solve this issue, by the usage of the balance tabs : 

 

These aileron tabs were fitted to all A6M2 Model 21 commencing with s/n3127 (construction no. 127) starting in February 1941.  Approximately 50~60 of this version were produced. But due to some unexplained accident pilots had a negative perception of them and were not eager to fly machines with them so Mitsubishi, until they figured what was the real problem, for safety, stopped further production. Eventually this balancing tabs were added again in A6M3 model 22 (produced since late 1942) and in Nakajima produced A6M2's. Nakajima. 

 

Although I dont have any actual performance comparison, there is A6M3 model 22 with those balancing tabs at Camarillo, you might be interested in reading the flight experiences of that one - http://www.avweb.com/news/pelican/185354-1.html?redirected=1 

"I climbed to about 8,000' at 150 knots, turning, pitching, playing with the airplane. It very quickly became obvious that the roll rate was very impressive, and it was fun going to full lateral stick deflection, rolling from a 90-degree bank one way, to 90 degrees the other, and back, but without loading it up. The roll response is just delightful."

 

 

Its also important to add that Mitsubishi designed a re-engined, clipped-wing design, with shortened ailerons.  This model was designated the  Model 32 (A6M3).  The roll-rate improved, but overall performance was not as satisfying as Mitsubishi engineers desired it to be. Only 343 of the Model 32 were produced. The RAAF on Eagle Farm performed a roll rate tests, which might be interesting here ;

http://www.wwiiaircraftperformance.org/japan/RAAF_Hap_Trials.pdf

 

It looks quite different, doesn't it ?

http://youtu.be/A9mxYKrDyrU

 

That is why I am very skeptical about the NACA 868 in regard to Zero as it does not refer to which model they tested,  any details about the forces. Especially as there were since 1943 available NACA tests of the A6M2 which are far more detailed. I would simply  put more faith into two following documents with detailed review of this machine, than document which gives no details in regard to Zero. In other cases NACA 868 is a very credible source.

 

I hope with this post I bright some interesting details and corrected some wrong view.

 

 

Constant altitude level turn performance is a small part of maneuverability.  Otherwise, the Japanese Zero would have won the pacific air war.   

No airplane wins the war. Pilots win the war. It was the lack of trained and experienced aircrews since mid 1943 that brought the doom to the Japanese. 

 

[GOAT-ACEOFACES]

That is some good stuff! 

 

Thanks for sharing!

Also, not sure if these tabs worked like the Fletner Tabs <SP> on the 109, but they too were tried and than done away with.. All in an attempt to improve the roll rate of the 109.. I have heard all sorts of rumors as to why they were disco, everything from bending and ripping off the wings, to pilot saying they make the plane too twitchy, but as to the sources of those rumors, I can not recall where I read that. So take with a grain of salt

 

PS Ill try and add that RR data to the chart

Edited February 15, 2015 by ACEOFACES

[=362nd_FS=Hiromachi]

Pleasure on my side, I've been trying to figure the discrepancies between the 868 and multiple other sources, yet there was no explanation. Possibly I could solve this by asking those who issued the NACA 868 report, but that will happen in another world

 

Edit : 

In the link above there is description of the operation of this tabs - http://www.avweb.com/news/pelican/185354-1.html?redirected=1

Edited February 15, 2015 by =LD=Hiromachi

[GOAT-ACEOFACES]

Added the data from the RAAF test

 

 

Enjoy!

[GOAT-ACEOFACES]

I read the RAAF report that Hiromachi provided and noted a few things..
 

R.A.F. HEADQUARTERS
Detail No. 119/A/30.
DIRECTORATE OF TECHNICAL SERVICES
SPECIAL DUTIES AND PERFORMANCE FLIGHT
REPORT ON BRIEF FLIGHT TRIALS OF JAPANESE FIGHTER TYPE 0 MK.II S.S.F. HAP.
16TH OCTOBER 1943
 
AIRFRAME:
The folding wings tips have been removed and replaced by short fairings, making the wing plan form square tipped and reducing the apan from 39'-4" to 36'-4"; the aileron have also been shortened. The firewall has been moved back 8 inches, the engine cowling lengthened and its shape improved. The position of the air intake has been changed and it is now situated in the top cowling.
 
Combat and initial flight trials had been carried out at Eagle Farm but the weight, C.G. position and position error were unknown and the instruments were not calibrated. Automatic photo-observers were fitted for the purpose of recording performance figures and rates of roll. It is, however, emphasis that the time available for the test was entirely inadequate for the work to be done thoroughly, and it was only due to the good luck and generally satisfactory weather conditions, that the short program originally scheduled was completed.
 
in testing rates of roll, information on control and wing stiffness would have been of great interest, but it was not possible in the time available to fit the necessary equipment required for this work.
 
Aileron Control:
The aileron control at speeds from the stall to about 140mph ASI is light and responsive and good rolls can be executed at 140mph. At speeds above 140 mph the ailerons become rapidly heavier until at 300 mph, the stick forces are very great and only very slow rolls can be executed. At high speeds only small stick displacements are possible. There is not much difference in the stick force or rate of roll to the right or left, although rolls to the left at low speeds appear slightly better. There is no aileron trimming mechanism.
 
A peculiarity was noted on climbs or fling above 27,000 ft. The ailerons started to stiffen up even at slow speeds, and at 35,000 ft. the were virtually frozen solid. on a subsequent climb the controls were, however, kept fairly free up to 33,000 ft. by continually moving the control, but even than the aileron became quite stiff to operate. The reason for these low temperature affects is not known.
 
An automatic photo-observer was fitted which measured degrees of roll and time. Stick movement, stick forces and aileron deflections were not recorded, as there was insufficient time to install the necessary equipment.

[=362nd_FS=Hiromachi]

I read the RAAF report that Hiromachi provided and noted a few things..

The folding wings tips have been removed and replaced by short fairings, making the wing plan form square tipped and reducing the apan from 39'-4" to 36'-4"; the aileron have also been shortened. The firewall has been moved back 8 inches, the engine cowling lengthened and its shape improved. The position of the air intake has been changed and it is now situated in the top cowling.

Yes, model 32 had a squared wingtips to improve the roll rate. The overall fuel carried was reduced due to longer engine, new engine cowling was designed, etc. etc. 

 

 

 

in testing rates of roll, information on control and wing stiffness would have been of great interest, but it was not possible in the time available to fit the necessary equipment required for this work.

That is because Americans insisted on taking the aircraft to United States for evaluation, at Wright Field. I have some documentation for those tests, but nothing significant there about roll rate. Interestingly RAAF found time for many many detailed descriptions and graphs, including position error correction. I wish all the tests of the Japanese equipment would be carried that accurately. 

[[BTEAM]_Shifty_]

Added the data from the RAAF test

 

COMPRR.png

 

Enjoy!

Thanks

And suddenly Zero is not bad at slow speed roll. In fact better than any opposition

 

How come they didn't test 109 here? Nor any other plane without wing mounted guns. Russian planes mount no guns in wings and later even removed some wing-mounted fuel tanks 

Its known that they removed wing-mounted guns on lend-lease P-40, P-39 and Hurricanes. All this to give them a better fighting chance (by saving weight and I assume improving maneuverability).

So altho there is no roll data for russian planes apparently they did care about roll rate.

Edited February 16, 2015 by [BTEAM]Shifty_

[GOAT-ACEOFACES]

Yes, model 32 had a squared wingtips to improve the roll rate. The overall fuel carried was reduced due to longer engine, new engine cowling was designed, etc. etc.

Ah, ok, so when I first read that, I thought they (RAAF/USA) were saying the (the RAFF/USA) replaced the folding wing tips with square ones.. Which I thought was odd, but what your saying is they (RAAF/USA) was simply making note of the fact that the Japanse replaced the folding wing tips with square ones.. But, for that to be the case, wouldn't the RAAF/USA have to have had a ZERO prior to this one to make that observation? Otherwise how would they (RAAF/USA) know it had folding wing tips before?

 

That is because Americans insisted on taking the aircraft to United States for evaluation, at Wright Field. I have some documentation for those tests, but nothing significant there about roll rate. Interestingly RAAF found time for many many detailed descriptions and graphs, including position error correction. I wish all the tests of the Japanese equipment would be carried that accurately.

But.. looking at the RAAF document, I see the plane was already in the hands of the USA, in light of the STARS painted on it.. Thus I was under the impression that the USA gave it to the RAAF for testing, after the USA testing, and simply wanted it back as some point.

[GOAT-ACEOFACES]

Thanks

And suddenly Zero is not bad at slow speed roll. In fact better than any opposition

True, but, at around 100mph, that is near stall speeds.. Real WWI type of Turn and Burn style of flying, problem was most pilots were trained NOT to fight at those low speeds.. But, those are the stories that tend to make it to print in that they are the most exciting, you know, the one on one dog fight.. Which was the exception to the rule in real life, and the norm in online gaming life, so we get kind of a twisted sense of what was good and bad about a plane IMHO by playing these games.

 

How come they didn't test 109 here? Nor any other plane without wing mounted guns. Russian planes mount no guns in wings and later even removed some wing-mounted fuel tanks

Sadly, roll rate test data is hard to come by, so much focus was on top speed and climb rates and climb times back than, thus that is what they typically took the time to document in graphs, and simply made verbal comments on the roll rates being good or bad.

 

Its known that they removed wing-mounted guns on lend-lease P-40, P-39 and Hurricanes. All this to give them a better fighting chance (by saving weight and I assume improving maneuverability).

Agreed

 

So altho there is no roll data for russian planes apparently they did care about roll rate.

True, but sadly alot of countries didn't document them in the form of a graph.

[=362nd_FS=Hiromachi]

Ah, ok, so when I first read that, I thought they (RAAF/USA) were saying the (the RAFF/USA) replaced the folding wing tips with square ones.. Which I thought was odd, but what your saying is they (RAAF/USA) was simply making note of the fact that the Japanse replaced the folding wing tips with square ones.. But, for that to be the case, wouldn't the RAAF/USA have to have had a ZERO prior to this one to make that observation? Otherwise how would they (RAAF/USA) know it had folding wing tips before?

Yes. As you can see it was not called Zeke but Hamp (or Hap), initially A6M3 model 32 was not recognized as a Zero-sen but a new type of fighter. It was identified by the Australian and American pilots as a new type over New Guinea, where it fought for the first time in Tainan Kokutai.

And well, the captured previously one Zeke - the famous Akutan Zero, although capturing was not necessary to spot the difference, it was enough to see the difference in combat Also Allies knew about the features like folding wingtips due to examination of the crashed and destroyed Zeros.

 

 

But.. looking at the RAAF document, I see the plane was already in the hands of the USA, in light of the STARS painted on it.. Thus I was under the impression that the USA gave it to the RAAF for testing, after the USA testing, and simply wanted it back as some point.

To quote this -> http://www.pacificwrecks.com/aircraft/a6m3/eagle_farm.html

 

 

Aircraft History

This aircraft was a hybrid assembled from the wreckage of several aircraft recovered from Buna Airfield during late December 1942 to early January 1943. The wreckage was loaded aboard a barge and shipped to Brisbanethen transported to Eagle Farm Airfield.

The Zero was made from parts of at least three Zeros including: A6M3 3028, (engine) A6M3 3030 (main fuselage and wing section) and A6M3 3032 (rear fuselage and other components). Plus, parts from other Zero wrecks found at Buna.

This aircraft was possibly designated with an ATIU Reference ID of XJ00. At one time, it appeared to be painted overall gray. Later was painted with American 'star & bar' markings.

Testing

With the aid of an interpreter and a Japanese pilot prisoner, the personnel were able to create a cockpit check list. On July 20, 1943, pilot William Farrior test flew this A6M3 Hamp for 25 minutes and tested the trim. No problems were encountered and no major adjustments were needed except for some trimming.

The next day, a second flight was made, but the engine cut out due to carburettor problems, causing it to ground loop after a dead stick landing. After the right landing gear was repaired, the airplane still had a tendency to ground loop, but this time in the opposite direction, so a tail wheel lock was secured and installed. This seemed to fix the problem. The brakes proved to be very inferior despite numerous relining, adjustment and checking of the system. As a result, all pilots were ordered not to use the brakes except in extreme emergency.

Later, it was shipped to the USA for further testing at Wright Field. It is unclear of its fate at the end of the war, likely it was scrapped.

Richard Dunn adds:

"Hamp EB-201 arrived at Wright Field with 69 hours and had flown 22 hours since arrived (91 total). A later report (29 April 1944) from Eglin Field shows they were attempting to fly the HAMP against the P-47 for comparison. However, scored piston walls, bent plugs indicated a new engine was needed. A 10 May 44 report says new cylinders and pistons installed but they were encountering trouble with the prop governor. The last data I have indicates they were still working on the a/c on 13 May 44."

 

 

 

True, but, at around 100mph, that is near stall speeds.. Real WWI type of Turn and Burn style of flying, problem was most pilots were trained NOT to fight at those low speeds.. But, those are the stories that tend to make it to print in that they are the most exciting, you know, the one on one dog fight.. Which was the exception to the rule in real life, and the norm in online gaming life, so we get kind of a twisted sense of what was good and bad about a plane IMHO by playing these games.

It has nothing to do with WWI but with combat experience in China. Chinese operated huge variety of aircraft and with support and training from various countries, including many American advisers they tried to fight. They had all kinds of aircraft, including Curtiss Hawk biplanes, Curtiss P-36, I-16s, I-15s, etc. etc. All those years of combat gave the Japanese a certain observations and experience which they employed into their designs, and so the requirement was range, armament consisting of machine guns and cannons but also a low wing loading so aircraft can operate from carriers.

 

This low speed characteristics were not based on anything from WWI but from the combat in China since mid 1930s. This affected the course of the designs and influenced tactics.  

 

Besides, Japanese often fought even at higher speeds and still could win this by the usage of many other maneuvers. Saburo Sakai had a lot of combat with P-400 and P-39s and often mentioned of the usage of the snap roll, etc.

[GOAT-ACEOFACES]

Yes. As you can see it was not called Zeke but Hamp (or Hap), initially A6M3 model 32 was not recognized as a Zero-sen but a new type of fighter. It was identified by the Australian and American pilots as a new type over New Guinea, where it fought for the first time in Tainan Kokutai.

And well, the captured previously one Zeke - the famous Akutan Zero, although capturing was not necessary to spot the difference, it was enough to see the difference in combat Also Allies knew about the features like folding wingtips due to examination of the crashed and destroyed Zeros.

Ah, now that make sense! Thanks!

 

It has nothing to do with WWI but with combat experience in China. Chinese operated huge variety of aircraft and with support and training from various countries, including many American advisers they tried to fight. They had all kinds of aircraft, including Curtiss Hawk biplanes, Curtiss P-36, I-16s, I-15s, etc. etc. All those years of combat gave the Japanese a certain observations and experience which they employed into their designs, and so the requirement was range, armament consisting of machine guns and cannons but also a low wing loading so aircraft can operate from carriers.

 

This low speed characteristics were not based on anything from WWI but from the combat in China since mid 1930s. This affected the course of the designs and influenced tactics.  

 

Besides, Japanese often fought even at higher speeds and still could win this by the usage of many other maneuvers. Saburo Sakai had a lot of combat with P-400 and P-39s and often mentioned of the usage of the snap roll, etc

Ah, if I said WWI, sorry, I meant to say WWI style of flying, which as you noted went well into the 1930s, where as WWII quickly became more and more of a BnZ air battle, thus the WWI 'style' of TnB became more of the exception to the dog fighting rule.

[=362nd_FS=Hiromachi]

Ah, if I said WWI, sorry, I meant to say WWI style of flying, which as you noted went well into the 1930s, where as WWII quickly became more and more of a BnZ air battle, thus the WWI 'style' of TnB became more of the exception to the dog fighting rule.

Well, if Japanese would have any other experiences from China than it would influence the designs differently. But they based on what Chinese and Soviet pilots did and how they fought. 

 

Although Japanese were not blind and quickly adopted some of the newest designs. The example of the low wing monoplane with high speed, very good roll rate and high wing loading was Ki-44. Seeing how Germans used the 109s, Japanese built the Ki-61. 

The Zero was a really sophisticated design with over 30 requirements given by the Japanese Navy, which were extremely rigorous. 

[GOAT-ACEOFACES]

Well, if Japanese would have any other experiences from China than it would influence the designs differently. But they based on what Chinese and Soviet pilots did and how they fought.

Agree 100%, the Zero was a 30s design and was based on what they learned in combat.. And as you noted, early on in WWII allot of the planes were 1920s and early 1930s designs and the tatics were still very WWI style. 

 

Although Japanese were not blind and quickly adopted some of the newest designs. The example of the low wing monoplane with high speed, very good roll rate and high wing loading was Ki-44. Seeing how Germans used the 109s, Japanese built the Ki-61.

Agreed 100%, as noted, WWII quickly turned into a BnZ style of warfare, and every country had to adapted to this change by modifying the planes they had or designing complete new ones.

 

The Zero was a really sophisticated design with over 30 requirements given by the Japanese Navy, which were extremely rigorous.

Agreed 100%, it was one of the first modern planes IMHO, that moved away from the WWI byplane fixed landing gear style of planes.

[=362nd_FS=Hiromachi]

Heh, you agree with everything ... no room for dispute than  

 

 

In case of roll rate I'm curious how Italian Mc. 202 behaves, I mean if we know something about Japanese aircraft than even less is known about Italian warbirds...