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The following image nicely shows the Genesis 2 wing airfoils. There is a 3 degree twist at the root end of the wing.
He has done lots of testing of zig-zag turbulators on the bottom of the wings.
The Genesis without turbulators had the unusual characteristic of touching down hard,
unless flown on at a speed of 50 kt or more. It also gave a sinking feeling in turbulent
conditions when thermalling at speeds around 45 kt. This was after a modification was done
at the wing root fuselage junction to eliminate separation at 50 kt.
With the aid of Profili, he tried turbulators on the entire lower surface.
The sinking feeling in turbulent conditions and the hard touchdowns on landings seemed to disappear.
I then removed the outboard portions in several steps to see if I needed all of it to improve the
low speed flight characteristics. I ended up with ZZ out to 22.5" from the root, where it is at 87% C;
near the root it is at 83% C. Without this ZZ, the transition on the lower surface moves back to the
TE and I guess it trips the top surface, causing the sinking feeling and hard landings.
We hope that Bob will take up the challenge to further investigate the LE deturbulator tape on the Genesis 2 wing.
It is important to know why this mod does not work on some airfoils and whether a variation of it may offer benefits.
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