Does anyone know what parameters Garmin uses to calculate % power? I've searched the manuals and relevant posts here on VAF. Didn't find much info on that aspect.
More specifically, I'm wondering if it takes into account AFRs and barometric pressure?
Not entirely sure but it seems to be based on the engine info you enter (displacement and horsepower) then it tracks fuel flow. You can leave rpm and throttle fixed but if you lean, the percent power drops. I wish it were more customizable. I don’t find it very useful, but maybe I’m just ignorant on how to use it.
I don't own one but was up test flying in a -10 today and didn't see repeatable results with TAS, and the same indicated % power at WOT LOP and part throttle ROP, same MAP, same RPM, same altitude.
Are there any items which maybe we don't have configured correctly on this one?
I am no expert on the system so would like to learn more.
Excerpt -
Engine Power
Estimated engine power can be calculated for Lycoming and Continental engines, using inputs from RPM, manifold pressure, and fuel flow sensors (all three all required for engine power calculation).
On the Engine Power Configuration page, select the appropriate engine type (Lycoming or Continental, turbocharged or normally-aspirated). Then enter the engine's maximum rated power and RPM (for example, 180 horsepower at 2750 RPM). For a turbocharged engine, enter the manifold pressure for maximum rated power. Configuring maximum manifold pressure is not required for a normally-aspirated engine, as it is assumed to produce maximum power at sea level pressure.