"C J Campbell" wrote
Actually, no we do not all worry about shock cooling. Neither do we all
worry about shock heating. Many highly respected pilots and mechanics
believe that shock cooling and shock heating are myths, at least for modern
aircraft engines.

First - we do not fly behind modern aircraft engines, at least in
trainers. Those engines are warmed-over 1950's (at best) technology.

Second, maybe those who are not worried about it should be. I know a
Bonanza pilot who didn't worry about it. He would routinely cut the
power way back for a rapid descent. I attempted to get him to stop,
but he just wasn't worried about it. Then he lost a jug on takeoff.
He's more careful now.

The manufacturers have also said that shock cooling and
shock heating should not be a problem -- of course, maybe they like to sell
replacement engines. :-)

The manufacturers haven't had any engineering expertise worth
mentioning. And I bet what they like to sell are not replacement
engines (few people buy one) but replacement jugs. The bottom end
never really gets hot enough to be concerned, but the jugs sure do.

I seriously doubt that shock cooling is much of a problem on training
aircraft, at least. These airplanes are subjected to all kinds of supposed
mistreatment, but their engines almost always make it to TBO.

How many of them make it to TBO without replacing a jug here and
there? None that I know of.

Michael