I would suggest that the best indicators for evaluating your (GA) fixed props
performance,
at a given pitch setting, are:
Indicated air speed for a given RPM at the indicated (or calculated)
fuel flow.
Density altitude try and do your test within a tight
temperature/altitude range.
Aircraft load (fuel + PAX + whatever) for comparative purposes this
must be as
consistent as practicality allows
In this context MAP is not much more than an interesting discussion point.
By definition you cannot have Static RPM once your aircraft is moving ( in this
context Static means no forward motion as in tied to a stump)
I do not agree with your comment on Static RPM Rotax specify a minimum of 5200
rpm (for Static/TO/Climb/Cruise). If you want to get the best service life out
of your 91 you should take notice of this Rotax 91 engines love RPM.
Your pitch setting will be for whatever aspect of flight you optimise it for:
Fine: will give you the best TO/Climb performance but will reduce high speed
cruise
Compromise: Something you can live with.
Course: Will give you the best Cruise/High Speed, but make for long ground runs,
anaemic climb and could quit easily compromise your safety. If your engine is
not making 5200 + rpm on the ground run/TO you may reduce its service life.
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