On Mon, 22 Aug 2011 22:02:17 -0700, Eric Greenwell wrote:

Now I'm curious - what glider and what initial airspeed did you use?

That may well apply to anything up to and including early glass and to
selected later gliders too: Juniors and ASK-23 both come to mind.

I checked my Std Libelle's zoom capability yesterday - at 3000 ft and
2800 ft, pulling up at a stabilised 100 kts both times. Each time I
pushed over as the speed came down toward 50 kts. Both went no lower that
42 kts and both gained precisely 300 ft. The rate of speed drop-off below
50 kts is dramatic.

Bottom line: As I'd guessed, I don't think a low pass and pull up is a
safe option in a Libelle.

Re elevator flutter stories: surely you'll only get control surface
flutter if you're over Vne or flying a badly maintained glider? Doing
either is unsafe at any altitude.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |