"Jay Honeck" wrote in message news:ruEbb.552072$uu5.90807@sccrnsc04...
When you're in flight, the lower pressure above the wing tends to
cause the skin to bulge up a bit, except where it's bonded to the
wing. My Cherokee 180 exhibits this behavior. In flight, you can
see the wing skin lifted slightly above the rivet line.

Hmm. I'm gonna have to check that out next flight.

Of course, this is why you have to ribstitch fabric wings.