Spin recovery vs tail design

At 13:56 12 May 2009, John Smith wrote:
Nyal Williams wrote:

I've never tried this, but I have wondered whether adding downward
deflected aileron on the outside wing during a spin might 1) add drag
that
would slow the rotation, stall that wing and further reduce the
asymmetric
lift, and thus aid in stopping the spin.

Spins are aerodynamically extremely complex and each aircraft type
reacts differently.


No question; that's why it's important to read the POH.

To answer your question: Outside aileron often flattens the spin because
it increases the drag on the inner wing, this accelerates the rotation,
which increases the centrifugal forces and therefore flattens the spin.
The consequence is twofold: The angular momentum increases while the
rudder becomes less effective to the point that the rotation cannot be
stopped anymore.

John Smith wrote:
To answer your question: Outside aileron often flattens the spin because
it increases the drag on the inner wing, this accelerates the rotation,
which increases the centrifugal forces and therefore flattens the spin.
The consequence is twofold: The angular momentum increases while the
rudder becomes less effective to the point that the rotation cannot be
stopped anymore.

By "outside aileron", I assume you mean "the aileron motion achieved by
moving the stick towards the outside of the turn/spin". Sometimes that
is called "top aileron", as when you are in a turn, and the outside wing
is the high wing.

--
Eric Greenwell - Washington State, USA
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