My Father worked in propulsion engineering. He worked on the Blackhawk, the Black Hawk, and he put the third engine in the CH-53. Kind of wish I had made my career there too.
Your dad did quite a job with the 53 Echo! got out of the Corps before they hit the Fleet, so I never got a chance to climb all over one. 13,000 HP going into that transmission! WOW!
The Delta had about 8,000 HP and the trans weighed about 2,500 lbs. IIRC, it had 300,000 ft-lbs torque on the main mast!
It sure was a kick to fly!