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Old 13th August 2009 | 08:53
  #26 (permalink)  
Keith.Williams.
 
Joined: Aug 2001
Posts: 775
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From: Dorset
If we are talking about gliding all the way to the ground then we will end up with a glide slope that is considerably greater than the usual 3 degrees.

Going back to the basics,

Glide range = Lift to Drag ratio x height

Rearranging this gives Lift to Drag ratio equals the cotangent of the glide slope.

For a glide slope of 3 degrees we need a Lift to Drag ratio of about 19 to 1.

Not many commercial transport aircraft will achieve this in the landing configuration.
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