ORIGINAL: bentwings

The easiest way to explain them is to picture just laying a flat sheet on top of the flap which extended forward of the hinge line about 1 inch as I recall. This was relieved into the wing to make it flush. When the flap went down, the part forward of the hinge line raised up. Under this part I made a vent as large and smooth as possible so air could flow down thru it into the lower face of the flap. I don't think flow was very good but they sure slowed the plane down and kept it from floating. As I recall I had to use some throttle and a warbird style glide slope on landing instead of just coasting in. I did try various lengths of spoiler but anything over about an inch did not improve it.

Message shortened by Taurus Flyer

I don't know why these were not very popular other than it was a lot of work to add them and keep the weight down. I guess I was not much of a pattern flyer then or now.