Thread: Flying Jumpers?
View Single Post
Old 03-03-2008, 08:27 AM
  #9  
rickair7777
Prime Minister/Moderator
 
rickair7777's Avatar
 
Joined APC: Jan 2006
Position: Engines Turn Or People Swim
Posts: 39,100
Default

Originally Posted by Kdub View Post
There is no such thing as shock cooling. Its an OWT that began in the 70's decades after the 1000+ HP aircraft did power off dive bombing runs and power off 'overhead' approaches, over and over again - never having problems with this fictitious condition. Why does this myth persist? There is no evidence for it.

The metallurgy is pretty straight-forward. Doing it occasionally is not likely to have a big effect, but doing it all the time will definately have an impact. You are effectively "shock cooling" an engine everytime you reduce power, but the magnitude and speed of the power reduction determines the metalurgical effect. The largest impact is on the top-end.

Trainers are lucky to reach TBO, and will often need a top-end prior to that.

A cruiser can easily go beyond TBO.

The OEM's didn't give us cowl flaps just for fun.
rickair7777 is offline