On gliders we have negative flaps for
flying fast (I have 2 negative flap settings).
This reduces the drag at higher speed.
Optimal settings are a function of speed
and weight.
As the gross weight of the aircraft increase
the optimum amount of negative flaps (or Aileron Reflex) would decrease.
For an airplane when running at higher
(indicated) speeds with an optimal amount of reflex, one would see faster
speeds and/or better fuel efficiency.
r.t.s.
From: Lancair Mailing
List [mailto:lml@lancaironline.net] On Behalf
Of Paul Lipps
Sent: Thursday, March 01, 2007
3:57 PM
To: lml@lancaironline.net
Subject: [LML] Aileron reflex
I have my ailerons reflexed about 3 deg up. As I have posted
in the past, through testing I found that varying the flap reflex with weight
and density altitude could result in a 1.5% change of speed. The higher the
density altitude and the higher the weight, the less reflex should be employed
in order to increase the wing's camber for the higher required CL. As camber is
changed on the NLF1 015F airfoil, the drag bucket moves along with it. You will
also have an added benefit of the fuselage angle being reduced which gives
better visibility over the nose.