On Wednesday, May 22, 2013 12:20:54 PM UTC-5, soartech wrote:
What is lost without them? One point of glide? What about sink rate?

Is this just for racers? My glider does not have them.

Does anyone have any facts on this?

Thanks.

When I got my LS8-18 off the boat in 2001 it did not have any mylar external seals on the top or bottom of the ailerons. It did come with two internal roll-seals on each side that seem to work very well. I'm still flying that way and have no indications that my glider's performance is lacking - quite the opposite. Aileron forces are delightfully low, no friction, no break-out forces. The gap itself is in the turbulent part of the wing and additional sealing would hardly make a difference. This would be different on a -27 or -29 where the bottom flow is laminar into the aileron/flap area and Schleicher is using seals consequently.
I like the simplicity of my set-up.
Herb