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Old 23rd Oct 2023, 18:29
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Bpalmer
 
Join Date: Dec 2012
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787 and A350 almost do

Originally Posted by Turbavykas
Hello

As you may know modern flapped gliders use negative flaps. It helps reduce drag at high speed. Well airlines always fly more or less near maximum speed while in cruise ... but at different weight. Maybe negative flaps could be used to always maintain one optimal angle of attack? I mean when the fuel is burned negative flaps are added.
The 787 and A350 both have cruise flap functions that will -without pilot intervention or action - adjust the flaps in flight to optimize performance. Earlier models (A330) moved fuel to adjust the center of gravity to optimize performance, but that required a lot of plumbing. This generation adjust the center of lift, instead of the center of gravity for a similar result with less hardware.
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