At 13:30 12 July 2005, Derek Copeland wrote:

We had a fatality in the UK involving an ASW20 that
dived vertically at very
high speed into the ground after a similar thermalling
upset. The flaps also
to some extent act as elevators and it was thought
that the pilot was unable
to overcome the nose down pitch tendency by pulling
back on the stick.

Not sure that is exactly right, the flaps tend to cause
the fuselage and tailplane to 'pitch down'. Ergo the
higher the ias the greater the angle of attack of the
tailplane and elevator. (The AoA of the tailplance
increases as the AoA of the wing reduces as the tailplane
is trying to produce lift 'down' rather than up relative
to the pilot). Pulling back on the stick increases
the AoA of the tailplane which could become stalled
and this would certainly cause it to be ineffective
as you describe.

My main original point was that the first action in
any sort of loss of
control situation in a flapped glider must be to select
neutral or negative
flap. If you have to open the brakes, do so before
Vne is reached

Absolutely correct, carve that in stone.

Derek Copeland
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Bert Willing wrote:
you're mixing up things. Speed limits for positive
flap settings have
nothing to do with g-load; they are to limit the forces
on the flap.