The tailplane has a Flettner strip, this is there to cut through the bounda
ry layer and break out of the "dead band" inside the BL. A Gurney flap is l
ike half a Flettner strip, one side only so it has a bias. People use it fo
r aileron trim, attaching the flap underneath makes it more discrete and th
is is the advantage. Not obvious and a bit ugly=0A=0AGraham=0A=0A=0A=0A=0A
=0A________________________________=0AFrom: Frans Veldman <frans@privatepil
ots.nl>=0ATo: europa-list@matronics.com=0ASent: Monday, 26 April, 2010 10:0
0:28=0ASubject: Re: Europa-List: PH-DIY first flight!=0A=0A--> Europa-List
message posted by: Frans Veldman <frans@privatepilots.nl>=0A=0AOn 04/26/201
0 12:38 AM, GRAHAM SINGLETON wrote:=0A> Frans=0A> a Gurney flap is a neater
alternative to a trim tab.=0A=0AI had to look up what this is. What I foun
d is that it is similar to a=0Aregular tab, but then with the "tab" stickin
g out at a 90 degree angle?=0AWhat is the advantage of this?=0A=0A> A short
length of=0A> draft excluder stuck on one side of the trailing edge will w
ork just as=0A> well as an ugly tab. Just like the elevator trim tab but on
e side only.=0A=0ABut this is called a Flettner strip, is that right?=0A=0A
That could indeed work as well.=0A=0AApart from the ugliness factor, which
-========================
|