Halton Brat is totally correct in his assessment of the strength of the Fiberglass copy of the old 1950s tin hat as one of the JT's on the Missile Servicing Flight at West Raynham that I worked with did the same but tried to make it really lightweight. The Mk 1 one version looked the biz, until he showed it off to some mates in the queue at the exercise mess on the missile site in the middle of a Minieval and one of them said 'God, this is really light', flexed it a bit and the thing broke in half (and guess that item the helmet designer didn't have to hand at work, the original). Anybody on here do that NBC trial at Honington in 87???
You think anyone had a hand in its design? It wasn't fit for purpose unless that purpose was to be uncomfortable and unstable, true it would our probably save your life, but only because you would suddenly dip down to pick it up... Ohh and that stud that pressed into your head, I still have the indentation from that.
I often wondered how the Army ran around in them, being RAF one took a more leisurely approach.