Robert Ehrlich wrote:

BTW, as I noted in another thread, spins are not caused by lack of
airspeed, but uncoordinated use of the controls -- at least in modern

Well, you have to precise what you are calling "uncoordinated use". I
remember an incipient spin in an ASH25 (can be considered as a modern
sailplane, although it existed well before I started gliding 9 years ago).

Of course the controls
were badly crossed, but some amount of cross control is normal in order
to counter induced roll and induced yaw, this is not an uncoordinated
flight, the yaw string is is the middle.

As I mentioned earlier, as the bank angle increases, and the
wingspan increases, the AOA of the inner and outer wing
can differ by several degrees with the yawstring centered.

I think we calculated for 18m wingspan and 30 deg bank, something
like 3 degrees, and 6 degrees for 50 deg bank. But hey, this
is just a newsgroup, please do the math yourself and tell us what
you get.

It was a bit complex to calculate. Radius of circle for inner vs.
outer wingtip, stall speed and sink rate and... I don't remember
all the details, but it seemed painful...

Eric and Marc (?) I think made good points that at steeper
banks stalls are hard to muster. So perhaps the 10-30 deg banks
are really what we are discussing...
--

------------+
Mark Boyd
Avenal, California, USA