Full span flaps and separate full Span ailerons?

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Riggerrob

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Cuffs should be outboard only for best spin resistance.
Vortilons are used for wings with sweep, I think.
The Cessna kits usually have a single upper stall fence.
Yes, vortilons solve a pitch stability problem that is caused by span-wise airflow on the outer wing panels. Many canards have suffered problems with deep stalls: early Rutan Long Eze, Velocity and Curtiss Ascender.
The problem solved is caused by wing roots stalling first, but turbulence from that stall migrating outboard until it stalls the outer wing panels. With outer wing panels stalled, remaining lift from wing roots pushes the nose ever higher. Fences prevent that turbulence from migrating outboard. Vortilons and the stepped inboard edge of cuffs all perform the same function, just in a smaller format. Vortilons and steps create vortices that act the same as wing fences.
 

Riggerrob

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Maybe 1.5”. But any attempt to extend forward defeats the purpose. It should be a large radius that droops. The Sportsman cuff is a poor design. Installation Pictoral
Why do you dislike the sportsman STOL kit?

Even if the Sportsman cuffs are a poor design, they pay for themselves within a year with faster climb rates. I have worked from Cessna 182, 205 and 206 jump-planes that had Sportsman kits and the extra rate of climb was always welcome.
 

Bille Floyd

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Cuffs should be outboard only for best spin resistance.
Vortilons are used for wings with sweep, I think.
The Cessna kits usually have a single upper stall fence.

YEP --left out the part where the wings need sweep
for the Vortilons to work --------------------------sorry !

Bille
 

speedracer

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I have over 2,000 hours in EZ's and the only ones that ever deep stalled were ones that were flown with the CG behind the aft end of the CG box. You can hold full aft stick (power off or full throttle) in a 60 degree bank and they won't depart, all the while with the canard bobbing up and down about 4" stalling and unstalling.
 

Riggerrob

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Sportsman STOL kit increases wing camber forward of the main spar. By moving the separation point farther forward and down, it "shallows" curvature over the critical first 25 percent of the wing. At that shallow angle of attack, the "big picture" angle of attack is reduced, so nose radius becomes less important.
 
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