Clareprop: Parachute landings (abandoning appropriate in certain circumstances). The military want you to survive them. Military Chipmunks had parachutes, hence bone domes worn. Same in Bulldogs.
Nomex suits - fire resistant, same as gloves.
Flying boots (still have mine!) - parachute landings
Cold weather jackets - Saves shivering while you waited for rescue after your parachute landing, etc etc
Applying civilian values to ex-military aircraft has never gone wrong, has it?