On Tue, 26 Jul 2005 05:46:12 GMT, "Bruce A. Frank"
wrote:

A while back I remember seeing an article in one of the aviation
magazines about the affect of squared off trailing edges on control
surfaces of light planes. Anyone know where such an article might exist?
So far I have found several Boeing and NACA publications on wings with
blunt trailing edges, or blunt trailing edges at supersonic speeds. But
little specific to light planes with top speeds of 150 mph and landing
speeds of 40 mph or less.

I seem to remember that the squared off trailing edge of ailerons and
tail surfaces improved control authority, particularly at slow speeds.
Anyone have an idea?

"As I recall" foggy memory and all, the air tends to attach to one
side or the other with a thin trailing edges. IE, it keeps switching
which can lead to an oscillation, or buffeting of the controls and
increased drag. The squared off trailing edge prevents this.
Although a bit faster, I believe the Cessna Citation has a "T" shaped
piece inserted in the trailing edge of the elevator or rudder (could
be both)

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com