the wing was trimmed with a scalpel. i wish i realised it before placing the reinforced tape.
I also found the wings edges (external, rudders) is not perfectly parallel! i had to cut 6 mm on one side to correct the problem. And the wings were glued together perfectly parallel.
Attaching the ailerons was then easy.
i added another 7.5cm / 3 inch wide reinforced tape ribbon on the top front and borrom front of the wings for better rigidity.
The final build is pretty rigid and resistant.
flight test with moderate-to-low wind with GC at 24 cm from tip. (allowed 24-26 cm from tip for best result. if GC is further back, then the aircraft is uncontrollable.)
the best view at 15 min. looping at 14 min...