Quite a lot of effort in my view - not to mention a thumb suck as where best and how far apart to place them given the marginal improvement on an already slow fabric covered aircraft. Of course those that have them swear by the STOL performance gain, which is human nature after all once you’ve paid your monies and spent the time – not so! ??
I spoke to 4 others with these VGs on various fabric planes and they all wished they would have installed them years ago.
?
If they don't work worst case, I'll take them off and return the product, but I don't see why they wouldn't work, especially underneath the horizontal stabilizer.
That was my gut feeling on it as well. On an aluminum or traditional dope and paint I could see it working, but the mylar/dacron has too much flutter and flexibility. I guess if someone was willing to risk damaging things by using two part epoxy or a mechanical fastener, maybe? Doesn't seem worth the risk in an attempt to reduce the stall speed of an already very low stalling aircraft though.