My comments on the ASW20C accident are based on my memories of what I saw at
the time, and on my memories of the subsequent investigation and report. I
never saw the actual report, but comments were published at the time.

The investigators estimated the speed when the glider hit the ground, it was
certainly of the order of 200 knots. I gather that the investigators
contacted Schleichers about the accident, and the information that the
glider would be unrecoverable at some speed below 200 knots, because the
pitch down force from wing twist would overcome the pitch up force from full
up elevator, came from Schleichers probably from Waible.

This accident is a perfect illustration of how the pilot is unlikely to know
what is critical if limits are exceeded. The ASW20C did not flutter, and
did not break up in flight; the first failure was loss of control.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Andreas Maurer" wrote in message
...


On Fri, 26 Mar 2004 14:00:08 -0000, "W.J. \(Bill\) Dean \(U.K.\)."
wrote:

I once saw the wreck of an ASW20C just after it crashed at about 200
knots. It turns out that the stability and control characteristics of
that type are such that above a certain speed it is impossible to
recover from a dive even with the stick on the back stop; this is
because the wing twists.


pretty interesting case - I had expected that the 20 (and 20C) would
lose its wings due to aileron/flap flutter at this speed.

snip

Bye
Andreas