Stolspeed VG's

Ok. Not full test results for me, but some in my 4A. Went up and flew it tonight after getting all the VG’s on the wings at 3.5% chord (aligned with middle of first rivet line) and all the VG’s on the horizontal stab lower side 4” from the elevator hinge. I did 60mm spacing from wing tip to inner edge of aileron, then 90mm spacing the rest of the wing to the root. 30mm spacing on the stab as directed.

Power off, flaps 3 plane just mushed in a steady decent at 43/44 MPH with no buffet or break/stall. Added a bit of power (1300rpm) and nose rises, slowly and steadily speed decrease. Buffet and stall with a break came at 35MPH. Straight over, no wing drop, good aileron control throughout. Was able to hold 37/36 mph and fly without a stall…..but once it goes below to 35, the buffet hits and the stall is quickly after it. Prior to this flap 3 stall was 42MPH. So 7 MPH reduced. WOW.!

I did not test any other configs tonight, was short on daylight when I got up at 5pm and wanted to do some landings. I did a couple flaps 3 landings and one full flap landing. Over the fence at 50 slowing to 45, push up a touch of power and enter the flare around 45 about a foot off the runway, with speed decreasing. Smooth touchdown at about 38 MPH. It really woke up the tail too. No weight in back and me at 280 up front and on the last one my 200lb dad up front with me, easily 3 point. I actually touched the tail JUST before the mains on 2 landings. Pretty dang impressive overall!

Thanks Virgil at Bearhawk for the chord suggestion of 3-5% based on their testing and testimonials on the earlier wing. Very happy with it. And I still got a 130MPH indicated cruise at 24”/2400 @ 4500msl. Same as before on my 31” ABW’s with baby bush wheel. So no loss in cruise speed​
 
A question for those using StolSpeed VGs. Did you use the recommended spacing of 60mm for the first 15 inboard from the wingtip and then 90mm for the remaining to the root? I've seen one post at least that mentions using 60mm for the length of the ailerons and then 90mm for those inboard. TIA.
 
I was the one that covered the length of the ailerons with the VGs at 60mm. Don't know how much that may have helped, but I am very,very happy with the performance vs no VGs.
 
Fred I recommend the std spacing. (Closer in front of the aileron)

Thanks. Member rod smith did the full length of the ailerons (67") using the 60mm spacing vs the StolSpeed recommended 15 VGs (35"). He reported better results than most. That's why I decided to ask. Thanks both for your feedback.
 
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I installed the Stolspeed VG product on my Horizontal Stab. With a stabilizer clean and forward CG I need weight in the back to three point with flaps 3&4. I hoped putting them on the bottom of the Horizontal would improve pitch authority in that configuration.

Yesterday I flew and took data with the clean stabilizer. Today I did another test flight with the VG’s installed.

I experienced no change. I had identical results in both pitch authority and performing power off stalls.

In prepping for this testing I modified the pitot tube with the goal of having accurate indicated airspeeds at high AOA.
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