SR71
Thanks for the hieroglyphics and the erudite discussion.
Unfortunately you didn't explain, in the banked case, how a horizontally derived portion of lift acting laterally on the fuselage can fail to cause sidslip. The contra force resulting from the sideslip is the balancing force is it not?
So I say again with some conviction
ANY imbalance in thrust on a multi, not having centre line engines, which is then flown straight by either rudder or bank or a combination inevitably results in sideslip. It is unavoidable
Then you refute the obvious in believing and stating that there can be an effect of cg position on Vmca. Derive all the weight you can to the horizontal and what do you get !!
In steady straight flight forces in the horizontal act around the lateral centre of pressure - NOT the cg. The cg can be anywhere until manoeuvre comes into the act..
Consider the directional stability of a twin engined dirigible having no apparent weight. Vmca when asymmetric ???
Looks like JAR 25.149 was prepared by someone having the same misconceptions and it may be important that we take steps to correct.
Hope you are enjoying this as much as I am.
We may have to fit a vane on a boom and do it all over again !!
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