Stefan,

I am currently chanting the "ball centered = no spin" mantra. However
I am very sympathetic to your explaination that its a difference in AoA.
In the end, that may be the purest way to explain the spin.

If this thread sustains I'll listen in and see what I can sift out.

Todd

"Stefan" wrote in message news:4bb62$4773ba89

While I agree that this is a correct and simple recipe and therefore quite
useful in practice, I don't agree that it helps to *understand* the
situation, because *reason* for the spin is not the yaw rate. The reason
for the spin is an asymmetric angle of attack, i.e. one wing is more
stalled than the other. Of course this situation can only occur if there
is some yaw, which leads us to the recipe given above.

Recipe: As there is always some yaw in a coordinated turn (otherwise it
wouldn't be coordinated), you can perfectly enter a spin from a
coordinated turn. Aerodynamic reason: The inner wing has a higher angle of
attack than the outer, so it stalls first or, if both wings stall, it is
more stalled. Asymmetric stall condition - spin.