Skydivers and Helmets
Comedian Jerry Seinfeld once joked that skydivers may as well wear party hats instead of helmets. His routine pivoted on the rather silly (well, he is a comedian) assumption that helmets were intended to somehow save your life in the event your parachute(s) failed.
So why do many skydivers bother wearing helmets? Well, they sure as heck won't save you if your parachutes fail. However, what they will do is protect you in other, much more common emergency situations associated with skydiving.
For one, a good hard helmet will increase your chances of remaining conscious after a clumsy fellow skydiver torpedoes you in freefall, or accidentally kicks you in the head as you and several other skydivers exit the aircraft.
Somewhere out there are skydivers who will confess to having actually slipped and prematurely fallen out of an aircraft on jump run. They will often boast about the mark their heads left after colliding with a landing gear strut or door jamb on the way out.
Another skydiver might also tell you about the time he landed down-wind and went running across the field, heels practically slapping the back of his head, before colliding with:
a.) another jumper (hopefully one wearing a helmet)
b.) the wind sock he should have been paying closer attention to before landing downwind
c.) Jerry Seinfeld and his party hat
Occasionally, often due to shifting winds (or an airplane emergency that caused jumpers to exit the plane away from the drop zone), skydivers find themselves landing off of the drop zone in comparatively hostile terrain. Pavement, sidewalks, powerlines, cars, buildings, street lights, power poles, broom-wielding grannys... smacking into any of these things while landing can leave you with a headache no pain killer can cure.
Although many skydivers can tell amusing, upbeat stories of unintended off-airport landings, I suspect most are not eager to repeat the experience, and some are glad they were wearing their hard helmets that day (or in some rare cases, that night).
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