Ramy wrote:

I hope we don't need to wait for the NTSB report, we all know what
they worth. Or Thelen's accident reports in Soaring Magazine, which
from some reason he can never get the details from those involved, and
have to speculate.
I wish Nelson speedy recovery.

Ramy

No need to speculate anymore. According to the NTSB report it was
disconnected aileron
http://www.ntsb.gov/NTSB/brief2.asp?...CA122& akey=1
I hope Nelson is recovering fine.

Ramy (who wonders why we had to wait for the NTSB report to learn
this)

Ramy's link didn't work for me, but this link did:

http://www.ntsb.gov/ntsb/brief.asp?e...02X00759&key=1

I've always believed that a disconnected aileron would not lead to loss
of control at speeds close to and above takeoff speed, and that the
danger was flutter at higher speeds. The glider would not respond as
quickly at low speeds, of course, but I thought it could still be held
level, turns could be made, and even spoilers used. Perhaps that is not
true, at least for the Nimbus, or perhaps the control was operating and
then fully disconnected, allowing the left wing to drop.

Can someone familiar with the Nimbus 4 M control hookups explain what
happens to the aileron if it is not hooked up at the fuselage? Does it
droop, does it move with the controls at all? Can it be partially
connected so it would appear to operate? Does it move with the flaps;
e.g., it the flaps were in negative during the takeoff roll, then moved
to positive to lift off, would this induce a roll to the left because
the left aileron did not follow the flaps into a positive setting?

--
Eric Greenwell - Washington State, USA
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