Chris: I have these estimated HP numbers for Oscar's plane
with the ELIPPSE two-blade: 242 mph TAS, 1000' dalt, 3200 rpm, 197 HP; 240 mph
TAS, 3150 rpm, 5500' dalt, 166 HP; 233 mph TAS, 3090 rpm, 10,000' dalt, 137 HP.
'Don't know how I got these numbers; 'probably a linear interpolation of rpm
based on a constant torque over the range at the charge density at altitude. My
125 HP O-235 Lancair with its 3-blade ELIPPSE prop cruises at 206 mph
TAS at 5500'dalt at 2880 rpm; the sea-level rated rpm on this engine
is 2800 rpm, so that 2880 is only 2.9% above rated. It goes about
213-214 TAS at 1000' dalt at 2950 rpm; again, that is about 5.4% above
sea-level rated rpm!
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