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Old December 27th 07, 05:07 PM posted to rec.aviation.piloting,rec.aviation.aerobatics
Dudley Henriques[_2_]
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Default spins from coordinated flight

Todd W. Deckard wrote:

But the links that Dan_Thomas sent me indicated that the airplane would not
stall "straight ahead" if you were in a climbing turn. The outside wing
has a higher AoA
which diverges even further as it initially drops.


Dan isn't wrong.
Climbing turn stalls are a bit complicated to nail down to a strict
behavioral pattern as each airplane and indeed each stall entered in a
specific airplane will probably be exhibiting slightly different stall
behavior due to varying control inputs by the pilot. The result of this
is that climbing turn stalls can produce different results depending on
what the pilot is doing with the airplane up to and at the instant of
the stall break.
Basically, if you are (as we say) coordinated, the top wing will stall
first and the airplane will roll off in that direction. The reason for
this is that as the stall is approached both wings start losing lift
causing the airplane to mush into a slip. The highest wing gets
interference from the fuselage and usually quits first. If you watch the
ball as this happens, as you get near to stall, you'll probably notice
that if you can't hold it centered, and a slip develops, that high wing
will usually be the one to go first.
This doesn't always happen however :-)) and if you skid the airplane,
the bottom wing can break first.
The bottom line is that in most climbing turn stalls, you will get a
roll off as the stall breaks, but remember, this is a ROLL OFF, not a
yaw rate!! Just reduce the angle of attack and use aileron to raise the
lowering wing and no pro spin forces are present.




--
Dudley Henriques