Good factor, and agrees with what I see with an Alon, C90, and 52" cruise prop. At 2450 rpm the expected TAS by the below equation is 115.8 mph (100.6 knots)...just about what I see. At a preferred 2350 rpm, 111 mph (96 knots). Pretty amazing efficiency, far better than what we get from our internal combustion engines. Almost as good as electrical transformers I think. Ralph Finch
From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Burkhead Sent: Friday, November 09, 2007 7:59 AM To: ety Subject: RE: [ercoupe-tech] Climb Prop -- Re: WEIGHT VS LSA My observation on typical Ercoupe models is that they have about 4% slippage from the theoretical speed they'd get from the pitch of the prop. i.e. airspeed would, in theory = Pitch (in inches) * rpm * 60 Convert that to statute mph by dividing by (12*5280) Then, multiply that times .96 to get expected true airspeed at low altitude. . <http://geo.yahoo.com/serv?s=97359714/grpId=19286938/grpspId=1705340085/msgI d=2306/stime=1194623950/nc1=4430620/nc2=3848614/nc3=4507179>
