Though for some time , why not a Bi Plane with flat inner surface Wings , for STUNT .
As in
More or less . ( Clarke ' Y ' .) Reversed to FLAT TOP for the lower wing . ( inverted airfoil .)
Would think a bit of convergance or divergance on the inner face alignment might help .
one of these , went whistling round inverted for a lap relitively effortlessly , in a ' bit of a blow ' at a field in a saddle in a hill .( its got FLAT UNDERSIDE WINGS ) .
OS 10 in a F Flight converted to C / L . ( had won F. F. Jnr. Scale at the Nats . If it'd been COMBINED F F & CL Jnr Scale , there wouldve been TWO entrants !
No More ! )
Cut almost upwind . say 15 knot . Hit the deck & it scooted tail up a half lap from top of circle to our boxes . A little more sheltered there . A ' Wheeler ' till stopped ! . RIGHT .
So since then , this we've wondered . !
But NOW , some silly sod has created an imaginary winged thing ( likely plastic or computor art . )
Excuse the Canard .
RIGHT , a very small gapped parrallel flat inner sectioned Bi Plane WING . !
SLOTTED , Even ! ?
Now we can get nasty .
And put the FLAPS in the FLOW between the Two Wings ! This'd approximate to ' blown ' flaps or control surfaces , full size .
Prevents the airflow breakaway under duress .
https://www.beyonddiscovery.org/aerodynamics-2/842-control-by-tangential-blowing.htmlSo . Next year everyone can do five foot square corners !
Well , would provide a unique design concept perhaps . Conventional plan fom even .
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So we make it not so imaginary by turning it into a half or 3/4 or 1 in gap .
But we keep the FLAP hinged about the centerpoint of the gap between the trailing edges , so its in a somewhat unobstructed aiflow . Or ducted airflow .
Where it says " center of pressure " the top & bottom are prised apart say 5 or 10 % of the chord. dimensional . Between the inner flat faces . creating a flow through & effectivly symetric action ! .