At 17:30 02 July 2006, wrote:
Thanks for the lucid and objective report. The accident
scenario you
describe is the stuff of nightmares! I am very glad
this did not turn
out far worse.

I do know the ship fairly well and have assisted in
rigging/derigging
it dozens of times. The wing attach mechanism is unusual
compared to
most gliders but it has been successfully employed
in this model of
aircraft for a couple of decades. It operated as-designed
the day it
was rigged and derigged in Tehachapi immediately prior
to this
incident. Your description suggests that the outboard
wing attach pins
were not (fully?) engaged. Does this appear to be the
case? Any
further speculation on my part is not relevant or helpful.
I eagerly
await the definitive report!

My condolences to you on the loss of the aircraft and
best wishes to
the pilot for a speedy recovery!

Best Regards, Mark

All indications are that the bottom pin failed for
some reason. While we are sure the right number of
turns were made to screw it in, (the pilot and my
son counted) and I personally verified it was flush
to slightly inset into the wing, the pin was missing
when I inspected the wing itself after the crash. The
connectors were not bent like the top two were so the
pin must have come out.

I'm not a mechanical engineer so I can't really evaluate
what happened, but the only thing I can think of is
that even with the appearance of being correctly inserted,
it must have been just slightly off and did not expand
out fully. The stress of the wing flex on takeoff allowed
it to come out and then the wing folded up.

Yes, thankfully the pilot is healing and will be back
in the air in a month or so, but it was so sad to lose
such a classic aircraft.

- JJ