Earnest,

If you were in the pattern and reduced power to the point where you were at
half throttle or below and the mixture then went to "near cutoff lean" it
seems you would be in danger of the engine stopping.  That might not be a
desirable thing when you are that low to the ground even if you were in a
pattern...??

Bill B

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On
Behalf Of Ernest Chrisltey
Sent: Thursday, September 06, 2012 10:19 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Single lever control

This is what I was referring to in my previous email.  Throttle is
graphed against RPM in both.  On the left, data points are colored based
on coolant temps at the time the data point was captured.  The right
graph uses AFR to set the color.

The one on the left has the points colored according to coolant temp at
the time the data point was collected. This graph tells me that a cold
engine will make more power.

The right graph has the points colored according to AFR, and is more
interesting. My throttle plate is fully open at about 50% travel of the
control lever.  My goal is to keep the mixture near cutoff lean until
after the throttle plate is wide open. Until WOTP (wide open throttle
plate) power increases from increasing the amount of intake charge.
After that, pushing the lever forward increases power by enrichening the
mixture.  I transition from changing the amount of mixture, to changing
the makeup of it.   I would like a solid diagonal line, correlating
throttle and RPM.  The graph shows me that I reach best power mixture to
quickly.  I need to shift my target AFR a bit so that the lines flatten
out with only 5% to 10% of lever travel left;  however, for the most
part I've achieved the goal of having RPM directly correlated with
throttle position.