"karl gruber" wrote

FADEC won't make an engine run more efficiently. It will make it easier to
manage.

In a way that is true, but at the same time it is as false as can be.

A properly leaned engine at cruise, with well matched injectors, will have
all of the cylinders humming happily along at the most efficient setting,
and lowest fuel flow. FADEC can not improve on that much, if any.

But, and it is a big but, think of the settings we run on takeoff, and
landing (in case you have to do a go-around) and of the time you are at
idle, or low power on the ground. You are running much richer than need be,
and not as lean as FADEC would have things set. On the average, us setting
the mixture is wasting fuel, and is inefficient as compared to FADEC. FADEC
will reset the mixture many times per second; as often as is needed. That
is something we can never begin to think about doing.
--
Jim in NC