What is "leaning out"?
In the passage before, it is said: if a pilot lost: climb, conserve and confess

Conserve meant reducing airspeed and "leaning out" the fuel mixture to conserve fuel and have more time to figure out where he is.

What does "leaning out" mean? Does it mean "using"?

Question

What is "leaning out"?
In the passage before, it is said: if a pilot lost: climb, conserve and confess

Conserve meant reducing airspeed and "leaning out" the fuel mixture to conserve fuel and have more time to figure out where he is.

What does "leaning out" mean? Does it mean "using"?

Answer

Lean is a common term a mechanic would use to describe the fuel to air mixture that an engine is using or consuming.

So to run "lean" means to use less fuel to air mixture then is normal in operation.

Answer

Lean and rich refer to the mix of fuel and air. To lean out or richen a nitro RC engine means to adjust the mixture of fuel and air going into the engine.

source:
http://rcvehicles.about.com/od/nitroengines/f/leanrich.htm

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