On Aug 30, 2:42*pm, "vaughn" wrote:
I think that accident investigators can fairly positively tell the difference
between a structure that has failed from overstressing and one that has failed
from fatigue. *The AD says "The preliminary investigation has revealed that the
fracture may have been due to fatigue". *So there seems to be little reason to
suspect this accident resulted from prior overstress damage; particularly damage
from a recent flight.

If a glider is routinely overstressed by, say, 20%, I would not expect
it to fail. I would, however, expect its fatigue life to be
significantly decreased. Years later, the wing could fail when under
"normal" load, and the fracture would look like a fatigue fracture. I
may be wrong... am I?

Bart