Ah, the very reliable RR Dart.
If ground fine not selected (or available) after landing, the engine had to be shut down because it would severly overheat otherwise.
Reversable propellors are nothing new, DC-6's and Connie's had 'em a long time ago.
On the first flight of the DC-6, 'ole Ben Howard (Douglas chief test pilot) backed it up for the audience.
Donald Douglas (Sr.) was not amused, so i'm told.