Yes he was, along with an alarming number of other pilots. I have read that it was a matter of the training not being adequate combined with primitive systems in the first P-80’s. Bong’s crash was due to a fuel pump failure combined with a missed item on the checklist involving the fuel system.
Those first engines were not like the ones hanging off the wings and tails of current airliners. I was talking to a friend who flies Atlas 747’s, and he says in ten years he has never had to shut an engine down. They don’t overhaul at TBO anymore, they just run them until they stop on 4 engine jets. Different rules for twin jets operating in areas without airports nearby, like the North Atlantic, they have to comply with ETOPS.