> Fred, Seems to be a bit of a misconception here. Gliders virtually never
> climb in a true sense, only in fact when they are being winch launched or
> when slowing up to enter a thermal. For the remaining 99% of the time they
> are going quietly down hill in their air mass, even though they go out of
> their way to find a rising air mass. Glider design aims for optimum
> lift/drag ratio between their thermalling speed of about 50 knots and the
> between thermal cruise of up to 100 knots.Increasing the L/D ratio is good
> news for Europas too. Regards, David Joyce
Gliders are usually flying at near the critical AOA, which requires the high
differential air pressure mentioned by Fred.
Gliders are often in a high bank angle turn (to stay in a thermal), which
certainly doesn't _feel_ like quietly going down hill!
Brian
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