Just to get the metal P-51 elevators out of the way...
Gruehagen's description of the reason for their introduction does not jive with numerous sources I have read that placed their introduction very late in WW II, at least for the European theater. Also the rear fuselage tank weight balance issue seems an odd reason for stiffening the elevator's surface. Note ALL post-war P-51s, including B and Cs, could very well display metal elevators WITHOUT this being relevant. In any case, the Potter-owned Mustang IV, at "Vintage Wings", is described on their website as having fabric elevators, which could also be wrong!
I mentionned metal elevators only as a counter to the odd combat account that might show superiority in 500 MPH dive pull-outs against the generally superior Me-109 moveable tail. In any case Me-109 pilots most often did not remember to trim tail-heavy in the dive, hence the baseless legend of impossible pull-outs (In fact, an actual strenght of the type!)...
BnZ says I mention tests nobody has ever heard of, well here it is; the test most relevant to my argument of poor 190 handling at high speed vs P-47D-4 (and of increasing P-47D turn rate past 250 MPH!). I did mangle some of the wording, but the points all bear out my claims;
http://img107.imageshack.us/img107/9568/pag17bm.jpg - (Below 250 MPH)"Turns were made so rapidly it was impossible to accelerate, and the ability of the FW-190 to HANG ON ITS PROPELLER and turn inside the P-47D-4 was very evident"
- (Above 250 MPH)"The P-47 EASILY out-turned the FW-190.... This superiority increasing with altitude. The FW-190 was very heavy in fore and aft control, (Me; possibly not exclusively a stick weight meaning? Since not "on the controls") vibrated excessively, and had a tendency to black out the pilot" (This last is odd, and suggest to me stick response was not progressive, but instead delayed with noticeable mushing that would be followed by a sudden "pitch up" leading to this comment.)
Incidently, I happen to believe the delayed response to elevator input control is obvious from much WW II footage depending on speed, and is probably a great unexplored area of WW II aircraft performance... Pilot/stick, stick/pitch, and pitch/trajectory are all areas of large variables in my opinion for elevators. Ailerons are much more predictable and quantifiable; they fight much less weight/leverage, and roll rate charts are thus usually more representative.
Returning to the comparative turn test, NO mention is made of a speed zone of relative equality in turns, which I find VERY telling. To me this probably means the P-47's turn response is STILL improving past 250 MPH, while the FW-190's is rapidly descending. Recent (1990!) tests of the P-51 and P-47 found the pilots saying the peak turn rate was MUCH higher than they expected, leading them to conclude that low speed turn performance was probably not that good...
Now note; "The airplane (FW-190) is quite nose-heavy, which makes dives near the ground dangerous". I mean... With Eric Brown's "addendum" to his see-saw tactic description ("EXTREMELY vulnerable on pull-outs"), the Russian's "perfect target" while "hanging" on pull-outs, U.S. pilots describing an 8000 ft. minimum to start pulling out or else... The INNUMERABLE descriptions of "pankaking" 190s, of which not one I remember concerning the 109... There IS a pattern here...
I think YES the 190 could pull 7Gs on pull-outs, but there could be a very long "lag-time" for that response to happen, and even when it DID happen, much of those Gs could have been generated in deceleration by an abruptly shifting, "automatic" tail-down "sinking", not turning, leading to the following inferior performance compared to an aircraft not immune to "sinking" itself!;
"The P-47D-4 had a DECIDEDLY better angle of pull-out." Suggesting the nose-heavy 190 wanted to stay flat.
Aside from Kurt Tank's 7G pull-outs on tests, which is quite well explained by the sudden "blackout" pitch tendency described in the test (following the lag-time of control response), I am really at a loss to explain where is there ANY evidence of great high speed FW-190A behaviour from actual flight tests, or from any combat report except when going straight...
The comparative with the F4U-1 and F6F-3 is very interesting, if a bit sparse on speed data. The equality in zoom after dives is interesting, and a potential counter to my point, but neither of the american aircraft were known for their zoom (the Ki-61 would out-zoom the F4U-1!), so the ability of the 190 to retain speed in the climb could have brought it to equality against these unimpressive zoomers... Also note that Eric Brown admonishes that careful pitch control allows pulling-out without "killing speed" by sinking, so we don't know if ONLY the height reached was used as the measure of the zoom performance, without considering the lenght. I don't think a test against the P-47D, P-38L and P-51D would have led to these optimistic zoom parity results...
That the F6F-3 out-turns the FW-190A-5 should be a surprise to no one; it was the only late american aircraft to tangle regularly with the Japanese, probably equal to most late Spitfires... The F4U-1 is an unknown quantity to me, but a factor should be remembered here. The actual FW-190A-8 ace on this Forum mentionned "catching" the stall with the ailerons, after a slight forward push on the stick, choosing extra aileron chord to boost this, boosting this further with SPACERS, having the broad wood prop, etc... You don't think American test pilots were that well versed in those shenanigans, do you?
Also THAT pilot, plus many others from several sources, ALL say the FW-190A-8 was a MAJOR advance in maneuverability over ANY previous model. You cannot assume just because it was heavier it did less well, which brings me to a possible alternative I found to wingload calculations;
http://www.sci.fi/~fta/JohnBo1.jpg
This is a turn rate performance chart from actual flight data comparing the heavier F-86 Sabre to the lighter Mig 15, both maximum and sustained. Josf14, in the following thread, makes quite a messianic point that this actual data chart goes against every precept of wingloading calculations, because the heavier/weaker thrust F-86 beats the lighter more powerful Mig-15 at low speeds in maximum turn rate.
If you forgive his difficulties with the English language, and his strange style of expression, I think he has quite a valid point. Here is the entire thread, hopefully, from the "FW-190 consortium" forum;
http://acompletewasteofspace.com/modules.php?name=Forums&file=viewtopic&t=8470 Of couse the countering argument is that a myriad of reasons could explain this "physical impossibility". He explains it as the extra weight allowing better speed retention throughout the turn, increasing the amount of air being moved out of the way in a given time.
I don't know. My theory is this, for all it's worth; heavier aircrafts, up to a point, have the equivalent of a higher center of gravity compared to the center of aerodynamic pressure; AS IF they were sitting more "top heavy" on a soft medium; this gives them an extra leverage, or tendency, to orient their axis of thrust OFF CENTER to their trajectory. This would mean the axis of thrust is at a SLANTED angle, meaning the axis of thrust is hitting SLOWER air relative to itself. This would increase the thrust more than the low-speed friction cost of being at too high an angle of attack. A primitive form of vectored thrust in other words...
Now I hasten to add this is just an impression planted in me by the expression "hangin on the prop", which in fact you encounter frequently when reading on the FW-190...
What I DO know for sure, is that an actual wartime FW-190A-8 Western ace said, on this very forum, that the A-8 model was a major advance in maneuverability over all previous Antons, with concurring opinions from other pilots about the very same variant elsewhere. (I think the main advance was due to the increase to a standard 1.58 ata power rating).
If you want to believe they bent the laws of physics improving those turns, apparently the laws of physics don't agree...
Gaston.
