Turbulence and airspeed

The V-g diagram is usually a good representation of this information.
The best SINGLE diagram I've found, IMO, is in the Jeppesen Instrument
Pilot Manual.

For Va (maneuvering speed), the angle of attack changes with speed and
load. If you are flying slower, your are at a higher angle of attack.
A gust from the front or below will increase the effective angle of
attack, and, before the lift increases enough to do damage, a stall
will occur (at least momentarily).
However, if the gust is strong enough from below, you can damage the
wings even if you are just dangling from a wire. The force on the
wings isn't from too much lift--it's from just blowing the wings off.

AvWeb had a discussion about this a few years ago; the information
might still be in their archives.

Flying Magazine, June 1996, page 106 had another fascinating article on
this as well.
Frequently, we seem to be taught that below Va, we can move the
controls to full extreme without damage. Well, flight 587 in New York
straightened us out on that. You can't go from one extreme to the
other repeatedly.

Another source of info is NTSB Safety Recommendation dated February 8,
2002.

A few years ago, I did a minor Civil Air Patrol seminar on this
topic--not in depth, just about 15 minutes or so. I have a very
thorough Vg diagram I put together from several different sources. If
anyone is really interested, I can try to dig it out of the archives;
it is a powerpoint slide, though quite detailed. I have no idea how to
put it up on the newsgroup, so if anyone IS interested and knows how, I
can email it to them.