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Old January 3rd 09, 05:00 PM posted to rec.aviation.soaring
Eric Greenwell
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Default High altitude flutter - Vne

Darryl Ramm wrote:
On Jan 2, 10:52 pm, Allan wrote:
Time to order your DuckHawk - 200 Kt Vne, 160 knot Va, 10.75 lbs/sqft -
just what you need for those high-speed wave flights!

But whats the L/D at 160 & 200 Knots? 10 & 5 ?

Allan


L/D? When the nose pushed down at 160 knots, crabbing into a 50+ knot
headwind and you've got +5 knots of up in wave you won't care...

I can't wait to see what magic Greg Cole pulls off with the Duck Hawk.


Darryl has it right - the limit for high speed wave flights is Vne, not
L/D. But, extrapolating from an ASW 27 B polar gives ~20:1 at 160 knots.
Attempting to extrapolate to 200 knots is pointless, so we'll have to
wait for Windward Performance to publish a curve.

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Eric Greenwell - Washington State, USA
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