fw 190a5 flight model

[Gaston]

Originally Posted by FC99

Structural limit for deformation is the one listed in manual, for fighter planes, safety factor was typically about 1.5 so plane with 8G limit will be expected to survive 12G. Between 8 and 12G plane will suffer permanent damage and in case of repeated over-stressing it will break even at values under 12G.
You can see in attachment where is the expected wing failure for one WWII fighter.

"Between 8 and 12G plane will suffer permanent damage"

Well, I figure in typical WWII aircraft the upper limit is 6 G (typical pilot limit) plus 2 Gs of engine-caused wing bending... So that is still 8 Gs total, and still within what you say is the start of permanent deformation...

An exceptional case is the P-51, which with G-suit could make the pilot tolerate 7 Gs, and probably added 2 "Gs" or more with the engine leverage...

So that makes for 9-10Gs... Hey, isn't the P-51 well-known for unexpected -and never explained- wing and tail failures? Hmmm... What a coincidence...

Also the P-51's wing obviously bent more than expected given its gun reliability record under turning Gs: Now isn't that another interesting coincidence?

Another interesting case is the Spitfire, which in my view must have added an exceptional amount of wing bending to its 6 G pilot limit: I figure up to 3 Gs, or over 22 000 lbs worth of extra wing bending over the "base" 44 000 lbs at 6 Gs...

This also makes for a total of 9 Gs, but the mutliple spar-inside-the spar wing construction was well-designed to bend, and could probably take that without huge risks... Unlike the P-51, the Spitfire is not known for wing failures, but IS known for wing deformation at high Gs with careless pilots... What a coincidence...

Since the pilot could not take much more than 6 Gs without at least losing his situational awareness in close combat, it does seem a bit strange these things were often damaged...

Gaston