On Jan 2, 5:40*pm, Darryl Ramm wrote:
Interesting to note that the damage I've seen in practice has been two
cases of elevator flutter with folks pushing too fast at high
altitude. I suspect that ignoring speed restrictions at ~18k' was the
cause. I believe the mylar seals were in good condition in both cases
and presumably not a factor. There are alligators in these here
swamps... be careful where you tread.

ASW-19 gliders were required to have an elevator modification that
substantially reduced the chord. The mod was required to prevent
flutter. Just one data point that suggests control surface flutter
may be more of a factor than primary structure in setting Vne.

Andy