<VV> Mixture - and airplanes

[corvair at mts.net]

Sorry guys, every piston engine pilot knows that max power is NOT found at full rich. You use full rich at takeoff at low altitude to cool the engine at high angle of attack/low airspeed/low cooling air flow takeoff conditions. It also prevents any tendency to detonate (ping) or lean sag (power drops off rapidly when the mixture is too lean). Takeoff mixture is too rich for max power. You get cooling because unburned fuel is going out the exhaust, taking heat with it.

If you're taking off at high altitude you can lean the mixture for more RPM, but watch engine temps!

At altitude you lean til RPM drops off then enrichen a bit, adjusting mixture for max RPM or just to the rich side of that. If you're lucky enough to have EGT gauges there's more scientific methods using EGT to set mixture.

Les

Message: 7
Date: Wed, 21 Sep 2005 10:25:46 EDT
From: NicolCS at aol.com
Subject: <VV> Jets for power
To: virtualvairs at corvair.org, AeroNed at aol.com
Message-ID: <195.47df252e.3062c76a at aol.com>
Content-Type: text/plain; charset="US-ASCII"

<good fuel stuff snipped>

Airplanes take off at "full rich" because that's where they 
make the most power. Once aloft, pilots lean out the mixture for good fuel 
economy and engine cooling.
Craig Nicol
<snip>I always thought that not fuel gave you more power, within reason. 
Someone  
told me tonight that leaner is better for power and more fuel will result in  
less power but less chance to damage the engine. Airplanes set "full rich" 
for  
takeoff and climb to get the most power out of the engine. The mixture is 
pulled  back, leaned out, in cruise for economy. <Ned>