Hi i've just discovered this forum thread and wondered if someone may be able to help? I'm struggling to get my 1944 L4 Cub to fly straight hands off!
Its in with maintenance now and I was flight testing some changes that were made yesterday.
Late last year we noticed that the aircraft had developed an apparently new tendency to roll left when hands off (with the stick moving left of neutral). After further investigation it was noted that
in order to fly straight and level with the ball centred, constant right stick force (but only very slightly right of centre) was required resulting in, contrary to logic, right aileron down float and left aileron up float. This was not apparent on the ground in the hangar with both ailerons neutral for that same stick position. Inflight the ailerons and stick naturally float to these off centre, left rolling, positions.
Maintenance suggested that before we adjust ailerons we make sure the aircraft is flying straight. Thus the rear struts (wash out) on both wings have been adjusted such that, when the aircraft is flying straight and in balance, the left and right ailerons are now neutral. The stick position is very slightly(1/2inch) right of centre which isn’t the end of the world. The wing dihedral has been checked and is symettretical. We are therefore satisfied that the aircraft now flies straight and true with the ailerons in their neutral position. Progress!
However (here’s the but...), inflight, the aileron positions still tend to a ‘left turning’ deflection. This has remained the same both prior and post the strut adjustments. Ie inflight, hands off, the ailerons deflect to roll the aircraft left. Right stick force is needed to prevent this still.
I wonder if anyone else has come across this or may be able to offer some advice on what adjustments need to be made?
My UK maintenance organisation is scratching their head as much as I am!
Thanks in advance!
Cubkiter