Aero engines, reverse torque, and my mechanical ignorance

[yosimitesam]

In the famous "Dracula" test where the British tested the Sherman, Centaur, and Cromwell tanks over a 2,000 mile course, the following opinion was offered by one officer concerning the Rolls Royce Meteor aero engine (600hp) used in the Cromwell:

"Doubtful as regards durability over 2,000 miles, owing to the stresses and strains experienced by the Meteor engine when mounted in the hull of a tank and subjected to reverse torque, which an aero engine is not normally called upon to do."

I assume the weight of the tank was responsible for this officer's observation, but my conception of this effect is somewhat "fuzzy". Would someone with a better understanding of exactly what this is and how it comes about fill in my ignorance with an explanation? Our esteemed 'snowygrouch' probably could fill this void in my knowlege, as well as many other members of this forum. Thanks.

"How terrible is wisdom when it brings no profit to the wise." - Sophocles

 

[MiTasol]

reverse torque occurs when the tank is running down hill so the tank is actually driving the engine.

If you have driven a manual shift car you will know this better as engine braking, especially when you go down a gear to maximise engine braking.

 

[yosimitesam]

reverse torque occurs when the tank is running down hill so the tank is actually driving the engine.

If you have driven a manual shift car you will know this better as engine braking, especially when you go down a gear to maximise engine braking.

That cleared it up. Thanks for the reply.