It would be nice if Ed and Tracy and whoever has a flying airplane would provide a list of data points - Altitude, Airspeed, RPM, MAP, Turbo (Yes/No) for example.  One could then plot a family of curves of power setting (MAP) vs. Airspeed at Altitude.  This would be very useful for extrapolating what one might expect to achieve a little outside the envelopes listed, and how one was doing vs the rest of the group.  Perhaps a spread sheet could be set up and filled in by the "flyers" amongst us and some graphs plotted to show everyone's results.  Get an idea what's actually happening.

Just a theory .... Jim S.

Ed Anderson wrote:

----- Original Message -----
From: "Greg Fuess" <gregory_fuess@yahoo.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Sunday, March 21, 2004 1:19 AM
Subject: [FlyRotary] Fuel Consumption Questions

Say you have a
hot 13B that produces 180 HP at sea level, then at 6000 rpm that would have
a fuel burn of 16.8 GPH.  Now you fly the engine at 7500 MSL at WOT, due to
the lesser density and oxygen content of the air at that altitude, 6000 rpm
at full throttle (if you can get it) would only produce 140 HP at a fuel
burn of 13 GPH if you have it enriched for full power with an Air/Fuel ratio
of 12.65.  Now at WOT and 6000 rpm you can vary the fuel mixture and get
quite a bit of variance in fuel burn (and therefore in HP).  Since the 13B
can be leaned out more than the Lycoming, I think you would find that fuel
burn at cruise leaned out would be lower with a 13B.--

Jim Sower ... Destiny's Plaything
Crossville, TN; Chapter 5
Long-EZ N83RT, Velocity N4095T