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Old 4th October 2009 | 21:55
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Wizofoz
 
Joined: Jun 2001
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From: Boldly going where no split infinitive has gone before..
Jumbo,

No, nothing to do with it. As I said, fly the light aircraft at best L/D, and the heavier one at that speed, and the heavier aircraft will descend more steeply. Fly them BOTH at best L/D and glide distance will be identical.

It's a little complicated by the fact that they are NOT gliding, and the residual thrust will have a greater effect on the lighter aircraft than the heavier one, but the principle is as outlined

The heavier one may have more energy to dissipate, but it will also produce more drag, so it kinda evens out.

35hrPa28,

Our answers crossed, but yes, you are right. HOWEVER the usual descent speed for jets are well in excess of their best L/D speeds, so in any usual situation, the heavier aircraft will glide further.
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