Prop pitch and field elevation
in General Tech Discussion
8 years ago
With the Sensenisch 3-blade ground adjustable prop I recorded the following static WOT RPM:
Elevation (feet MSL) Pitch 1 Pitch 2
920 5200 4950
20 5400 5150
Same prop, engine (912UL) and aircraft, the lower elevation data 13 months later.
The question is this: wouldn't one expect static WOT RPM to be *less* at sea level because the atmosphere is denser and thus there is more drag on the prop? The Bing compensates for atmospheric pressure differences in mixture, right?
Obviously there are other variables (I'm thinking fuel quality) but in theory shouldn't less dense air mean greater static rpm?
Incidentally at Pitch 3 i know see 5010 rpm, which will be my starting point for flight tests.
Elevation (feet MSL) Pitch 1 Pitch 2
920 5200 4950
20 5400 5150
Same prop, engine (912UL) and aircraft, the lower elevation data 13 months later.
The question is this: wouldn't one expect static WOT RPM to be *less* at sea level because the atmosphere is denser and thus there is more drag on the prop? The Bing compensates for atmospheric pressure differences in mixture, right?
Obviously there are other variables (I'm thinking fuel quality) but in theory shouldn't less dense air mean greater static rpm?
Incidentally at Pitch 3 i know see 5010 rpm, which will be my starting point for flight tests.
