VG's revisited

[C5Engineer 1170]

I put Stolspeed VG's on my Horizontal stab was happy with the results. I've been in touch with him again recently regarding wing VG's on a HH STOL wing. He said he only knows of one person with an Avid that has reported good results back to him. That guy put his at 90mm behind the leading leading edge. I can do my whole wing for $100 so it's not a huge waste if it doesn't work out. I'm looking for any other numbers floating around out there for a good distance. It seems between the flaperons and the dips between the false ribs it's not quite as straightforward as it is with other wings to install them.

My Rans S-7 big tire buddies swear by them. What do you guys think?

[SuberAvid 617]

Joey,

I think they helped a little lowering the stall on my wings but not huge. I may have placed them a little too far back though; I placed them at 10% of the chord length back from the leading edge (per the instructions) and they seem to be farther back than a lot of Supercubs I have looked at. The best benefit I found from them is they added aileron control authority that I didn't expect. Quicker and more powerful roll response. Not sure why they did that with the flaperons under the wing but it sure made a difference on mine. I think they were worth the $100 to me. Jack put the leading edge cuff on his wings which are supposed to do everything the VG's do and more, so it will be interesting to compare our planes when he gets his done. Too bad everything doesn't give the 25% improvement multiplied by each dodad...

Speaking of dodads; how about someone building leading edge slats for the Avid like the Dakota cub wings? I seems like you could epoxy and rivet the tabs onto the leading edge spar at every main rib location and then bolt the fabricated slat to the tabs. Take a look at this in the latest Kitplanes.

Brett, are you listening?

[6320012s 12]

I added vg's to my KF 3 at the 10% location and like suberavid, found they really helped aileron control.. especially with full flaps. I also put them on the under side of the tail, and that seemed to give better flare authority. Unfortunately, I made a few other mods at the same time I put them on, so I can't be sure how they affected cruise, but it seems like they had little effect.