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Re: Performance of the Fw 190A on the Deck?
[quote=Crumpp;70205]
Weight very much affects our aircrafts envelope. It has a direct relationship with velocity.
V2/V1 = SQRT(W2/W1)
[End quote]
No. Weight affects the envelope, indeed, but the direct relationship is wrong. For aircraft of this vintage, it is probably true that induced drag has a linear relationship with weight, but induced drag is only part of the story. The effect of weight on speed varies with altitude, because it varies with induced drag only, and induced drag increases with altitude (at any given speed). At low altitude and high speed, the drag term is dominated by the zero-lift drag. This is made up of skin friction drag, profile drag and excrescence drag, none of which vary with weight.
For high altitudes and low speeds, the effect is reversed, as the drag is dominated by the lift-induced drag, and the top left corner of the envelope is notably smaller at higher weight. The bottom right is hardly affected.
I made my living doing these sums. There's a lot about aircraft performance I never knew, but I think this is fairly basic.
The rest of the posting is sound, and a very useful addition.
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