Reflexing the flaps reduces lift, but if the change in pitching moment reduces
trim drag enough, you could be ahead of the game, but it is airframe-dependent.
Could slow a given airframe down I read.
10 degrees is a lot of reflex, but the Lancair 320 has small flaps. Reflex big
flaps enough and testing is needed to make sure the thing won't ever have a
dangerous
CG condition, which can't be corrected should flaps fail to deploy.
But theoretically, reflex 'em just right, leave the horizontal tail at home as
we now have a sort-of flying wing, and better than 10-knot boost with all that
wetted area gone. Pitch control with the tri-gear's flap switch?
Regards,
Fred F.
> I struck up a conversation this morning with the owner of a beautiful
> Lancair 320. With a Lycoming 320 engine, he cruises at 75% power at 7,500
> feet, at 195 KNOTS! I asked him about his speed "tricks" and he said that
> one of the things he did was to "reflex" the flaps to 10 degrees UP when
> fully retracted. He said he gained about 10 knots of speed just by doing
> that.....versus the zero degrees normal retracted position. The theory is
> that reflexed flaps reduce wing drag dramatically....
> Garry Stout
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