DB,
There was also the case of Geoff Bader in an S58T in 1976(?) landing on the Forties when he suffered tail rotor buzz on landing and his helicopter crashed on to the deck of a crane barge which was alongside at the time. The corner of the overhead console fractured his skull. Luckily he survived and after several years managed to regain his medical and last I heard he was flying for BA FW.
When I was flying SAR on the Brent we never had helmets, though our winch men did. There are a number of pilots in Nigeria now who wear helmets and after seeing the damage done to one of our S76s here by a bird strike a few months ago, I must admit that I have been considering getting one. The main thing which would bother me in this climate is the effect of wearing it for a long time on hot, humid days. I always wore one in the military, but that was pretty uncomfortable after a few hours, but when doing survey flying in the 212 in Iran we were issued with Gentex helmets which seemed pretty comfortable, though they never fitted quite as well as the UK mil helmets, so I did wonder about the difference in crash protection of the two.