On Mon, 19 Jan 2009 14:23:57 -0500, Tman
wrote:

Somebody posed that seemingly simple question to me, but kept coming
back to the point that they stumped me.... And I am stumped. What do
you see wrong with the logic in this dialog?

Q: Why do I need to lean out my carb when I climb?


like most arguments in aviation this one arises because a question is
asked with a misleading part in it.

"why do I lean my carb when I climb" is a bull**** question open to
much misinterpretation.

the fact is that most airfields are near sea level, say under 1,000ft
elevation anyway. there is actually no need to lean a carby at these
altitudes.
in fact the mixture is left rich so that as you climb the over rich
mixture aids in engine cooling.
continental's pilot notes will tell you this.

"why do I need to lean my carburettor at higher altitudes" is probably
a better wording of the question.

that is simple. the air is less dense so the amount of fuel it needs
to achieve full combustion is reduced. the density of the fuel doesnt
decrease so you need less of it.

learn to think in more precise terms and a lot of the confusion
vanishes.
Stealth Pilot