Heavy wing/aileron dispalcement

[Simon Hitchen]

Hi guys, I've searched and searched but can't quite find what I'm looking for.

My 7 does has an aileron issue. On the ground everything, all wing trailing edges, line up beautifully. The angle of incidence is equal from tip to tip. Aileron alignment tool is bang on. I've measured the pivot point to aileron centre line on both ailerons inboard and out, exactly the same. The aircraft flies with the ball in the middle at cruise. All fairings measured straight with a laser.

In flight if I hold the ailerons in trail to match the wing tips and inboard flap position there is no rolling moment, it flies beautifully straight. If I let go of the ailerons with trim centre, the left aileron raises slightly (about 1/8th of an inch) with corresponding downward deflection of the right aileron and I roll left. It's trimable with about 3/4 trim at cruise speed.

Something to do with the airflow is causing the ailerons to deflect. It's certainly an airspeed dynamic pressure issue as the effect increases with airspeed. I know it can't be a flap position error because if I hold it all in trail it flies straight. I'm leaning towards adjusting the vertical position of the aileron (not sure which one yet). Any thoughts please?

Thanks

[ShortSnorter]

I recall a previous thread: A hole on inboard/outboard rib of the aileron was causing a pressure difference in flight, which I believe was causing heavy controls during flight operations.

[rvbuilder2002]

Your didn't mention that you had checked the aileron trailing edge shape as described in Section 5
It can have a big influence on exactly what you describe as the problem.

[Simon Hitchen]

On further examination the left aileron outboard end is sitting a little higher with respect to the wing top skin and tip than the right aileron outboard end. I think I'll slot this bracket and lower it a little.

Thanks Scott, I did examine both trailing edges and found the right aileron a little fatter so gently squeezed it to match the other side. That certainly helped a little.

Simon

[JDA_BTR]

Is it also possible your aileron trim isn't truly centered? So you are putting just enough pressure on the stick to line it all up but when you let off the trim takes over?

[Carl Froehlich]

Originally Posted by Simon Hitchen

On further examination the left aileron outboard end is sitting a little higher with respect to the wing top skin and tip than the right aileron outboard end. I think I'll slot this bracket and lower it a little. SNIP
Simon

A better option is to get the no hole aileraon bracket from Van?s and drill a new hole to rehang the aileraon. Try the slot technic to find the right height, then rehang with the no hole in the same place.

Carl

[Simon Hitchen]

Exactly what I thought, slot the brackets to find the correct placement and then drill the new brackets to match permanently.

[Simon Hitchen]

I slotted both brackets and moved the aileron down by 1/32 of an inch. All sorted, heavy wing problem fixed.