Was he a hard hat diver?
Yep!
In that era, we used Mark V diving helmets, SCUBA (Self Contained Underwater Breathing Apparatus), & Jack Brown masks (full face mask with surface supplied air). Another rig used by First Class Divers and Master Divers was similar to the Mark V but it was used in deeper dives and the breathing mixture was helium/oxygen. The reason for the helium mix was on deep dives, nitrogen narcosis could set in at great depths, leaving a diver "drunk" on nitrogen. Helium replaced the nitrogen and mixed with oxygen eliminated the narcosis.
Mark V's were phased out in the early 80's I believe to become collector's items.
His accident occurred around the time I was going through Second Class Diver's School in Subic. I had not heard of him until the movie was produced.
All that being said, CONGRATULATIONS Master Diver Carl Brashear!
Salute.....two