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Old 27th March 2005 | 14:52
  #11 (permalink)  
Intruder
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Joined: May 2000
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From: Seattle
Given that Lift = W Cos (Angle of Descent) you will be at the point of maximum lift when you minimise the angle of descent, i.e. at best L/D ratio.
Actually, not. Maximum lift will give you the minimum RATE of descent, without regard to angle of descent or distance covered in the glide.

In a glider there are several speeds normally considered (these are only quick descriptions, not technical diatribes):

Minimum sink: Just above stall speed, it gives you the least rate of descent, which translates to the greatest rate of climb when in a column of lift. It also gives you the smallest turn radius, helpful for staying inside narrow columns of lift.

Max glide: At L/D max, gives you the greatest still-air distance in the glide, without regard to the time it takes to get to the ground.

"Speed to fly": Calculated dynamically, based on the specific aircraft, winds, available lift/sink, distance to go, and time constraints. Used when racing, to get the farthest the fastest without hitting the ground.
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