JJ, you are about right on. I strongly suspect that if a glider "stalls"
but retains aileron control, the wing didn't really stall - just the
horizontal tail lost its grip on the air and let the tail pop up (Nose pops
down). Normally, this is a pretty benign way to limit minimum airspeed.
Adding any device to increase up elevator authority might allow the pilot
bring the whole wing to stall with the possibility of a spin departure.

It seems to me that the only reason to increase up elevator authority would
be to improve thermaling and then only in the case of a glider whose minimum
airspeed is limited by up elevator ineffectiveness. A case might be the
G103 Twin II when the CG is near the forward limit. This limits minimum
airspeed to well above minimum sink in a steep turn.

Bill Daniels

"JJ Sinclair" wrote in message
...
Kirk,
I agree with you that competent, current pilots, don't inadvertently stall
any
ship. But your statement that you like a crisp stall, got me wondering.
How do
you like a crisp stall, in the pattern, after some hard maneuvering to
avoid a
mid-air? How do you like a crisp stall, when on the rocks, and get hit
with a
large tail-gust?

The stall I got in my LS-7, after adding zig-zag to the horizontal stab,
was
the worst stall I have ever seen in any sailplane. I mean she went near
vertical on me. Don't care to duplicate that in the above situations.

PS, I suspect the zig-zag delayed the *normal* seperation on the stab, but
when
it did seperate, I lost all the down force from the horizontal stab and
that
gave me the near vertical pitching moment. The wing may not have stalled
at
all. Now someone please feel free to tell me just how full of Ka-ka, I am
about
aerodynamics.
:)
JJ Sinclair