Another contributing factor to necessary stabilator force required is engine
angle.
An easy check would be to trim for normal cruise speed with engine running,
note trim position and measure precise location of stick (string or ruler).
Then kill engine, prefer if you can feather prop, but stopped prop is
sufficient,
then with trim in same location and stick brought to precise location see
what speed you achieve. If speed is greater than engine on cruse speed you don't
quite have enough down engine angle (prop end not down far enough) for most
efficiency and vise versa (less speed and too much down engine angle).
On models and full scale having a slight positive nose up pitching is not a bad
thing.
BTW similar technique can be used to dial in CG on a model, motor off trim for
a few MPH over stall, then dive to maneuvering speed and put stick in exact
position
it was to achieve trim a few MPH over stall, if it pitches wildly up you
are too nose heavy for most efficiency. Again a slight nose up pitching is
desirable
Ron Parigoris
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