Having now got a few test hours on G-MIME we found that it needs a small
amount of aileron trim with a passenger aboard. As the intention is to fly
the aircraft mainly with 2 POB I am trimming it for that configuration. The
differences in aileron trim for different airspeeds seems very small so
having an electric trim just to cope with two main settings seems
unnecessary as well as being expensive and adding extra weight. If a trim
servo is mounted in the aileron is it not going to require a large weight
increase to rebalance the aileron? This would probably need another lead
weight and balance horn.
My inspector gave me a good tip for a fixed trim tab. Rather than making
one from aluminium (which is difficult to adjust once it is fixed to the
aileron) he suggested using a wedge of balsa wood (similar to the flettner
strips) just on the underside of the aileron. This can be taped on
initially and its length adjusted until it is just right. It can then be
stuck on permanently and painted. It has two other advantages. Firstly the
weight added is small minimising balance problems and secondly it is only
visible from underneath so it doesn't spoil the look of the trailing edge.
In the rare event of a long solo flight an extra piece will be temporarily
taped in position.
Nigel Charles
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