Leaning with EGT?

It is my understanding that the computers in cars use oxygen sensors in
the exhaust and not EGT to keep the mixture right. My question is why
not use oxygen sensors in airplanes? Is EGT easier to interpret when
it's a human instead of a computer controlling the mixture or is it just

that it's always been done that way?

--
Chris W
Oklahoma City

"They that can give up essential liberty
to obtain a little temporary safety
deserve neither liberty nor safety."
-- Benjamin Franklin, 1759 Historical Review of Pennsylvania

Chris W wrote:

It is my understanding that the computers in cars use oxygen sensors in
the exhaust and not EGT to keep the mixture right. My question is why
not use oxygen sensors in airplanes? Is EGT easier to interpret when
it's a human instead of a computer controlling the mixture or is it just

that it's always been done that way?

--
Chris W
Oklahoma City

"They that can give up essential liberty
to obtain a little temporary safety
deserve neither liberty nor safety."
-- Benjamin Franklin, 1759 Historical Review of Pennsylvania

For one thing avgas with lead in it will poison the O2 Sensor rendering
it inoperable. We may see O2 sensors sometime in the future when avgas
goes to unleaded. Also the egt would measure the richer range better
than an O2 sensor because the amount of O2 remaining is so small.
Jim Stockton

On Thu, 18 Sep 2003 11:03:30 -0500, Chris W wrote:

It is my understanding that the computers in cars use oxygen sensors in
the exhaust and not EGT to keep the mixture right. My question is why
not use oxygen sensors in airplanes? Is EGT easier to interpret when
it's a human instead of a computer controlling the mixture or is it just

that it's always been done that way?

--
Chris W
Oklahoma City

The oxygen sensors cannot tolerate leaded fuel.

Corky Scott

"Chris W" wrote in message ...
It is my understanding that the computers in cars use oxygen sensors in
the exhaust and not EGT to keep the mixture right. My question is why
not use oxygen sensors in airplanes? Is EGT easier to interpret when
it's a human instead of a computer controlling the mixture or is it just

You'd better stay away from 100LL then. The auto oxygen sensors will
be ruined by lead. The main reason is simplicity. No "computer" is
required. The EGT therocouble is about as simple as instrumentation
gets.