K.P. Termaat wrote:
Yesterday evening I talked with a friend about avoiding excessive speed when
recovering from a spin in a modern low drag glider with the somewhat larger
span.

A lot has been written here about G loads. I recall that the
T-34 (an aerobatic power plane I have a little time in
which is sortof a tandem Beech 33) had some issues with wings
coming off during aerobatics. The recorded G loads and mauevers
indicated the aircraft wasn't flown outside of G limits.

How did the wings separate? Some smarty folks said it was
because the twisting G load that the wing could endure was
much less than the static tested load. If the ailerons were
deflected and the thing was in a steep spiral (as opposed
to straight dive) there were twisting loads.

Now I ain't no aerodinymakist. I took a plastic spoon and
tried to bend it in half. No luck. Took the same
spoon and twisted it and bent it in half. Bingo. What
does this mean? Don't make wings out of plastic spoons...

Anyway, I also recall the Sprint Ultralight had some airframe
separations, and before I flew it the first time, the
owner (who was also an A&P) told me he'd installed additional
bracing wires to reduce wing twisting.

Come to find out, there are more than a few aerodyne designs
which use drag and anti-drag wires (maybe the wrong technical
name but yo get the idea) inside and outside the wing to help
prevent twisting.

I tell ya, I'm personally a big fan of wings-level
dives vs. spirals. I'd go 1.2 x Vne in a dive before I'd go
1.0 x Vne in a steep spiral. Dunno if this is right,
but that's what my instinct tells me...
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Mark Boyd
Avenal, California, USA