Comment by serf | Hacker News Reader

Comment by serf | Hacker News Reader

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don't know how big a deal the harness really is. Even getting out of a helicopter underwater with a regular 4 or 5 point harness with a single-point twist buckle after a crash, especially if the vehicle isn't perfectly vertical, if there's debris or gear inside, etc. is going to be very difficult for anyone who hasn't trained in it.

Well, the pilot -- wearing a normal belt -- was the sole survivor; and claims that he tried to disengage the belt of the passenger next to him unsuccessfully before escaping.

from the NTSB preliminary report:

"After impacting the water, the chin bubble on the pilot's side began to fill with water, which quickly covered the floor. He kept his restraint on and reached down for the front seat passenger's carabiner attachment to the helicopter. He turned the knurled screw "two or three rotations"; by that time, the helicopter was "listing past a 45° roll." He then decided to egress the helicopter, and by the time he unbuckled his restraint, he was fully under water."

If the harness is anything like the harness I bought from Home Depot to do work on my roof, it would be nearly impossible to get out of quickly. The nylon is the super stiff abrasion resistant kind as well, which I cannot imagine cutting through quickly with a normal strap cutter, which is basically just a razor blade in a plastic handle.

The fact that they were screwed to the floor sounds makes it sound egress would be nearly impossible in an emergency. The way those harnesses are designed there is almost no way to free yourself if they are under tension. You effectively need to call someone else to help you get out.

On top of all that, the mammalian diving reflex means that unless you are experienced and well-prepared you are probably going to gasp as you go under water. Even a strong swimmer can drown due to the effects of the diving response, most commonly in a chaotic situation where they don't have the time or space they normally would to recover.

Of course given the chaos I don't think you could say everyone would have survived with different belts on, but I think it would have been much more likely.

And of course, you don't want the harness to detach easily under tension either (that sort of defeats the purpose). Tricky tradeoff; and it really looks like this company cared about their revenue much more than safety, and was not in a position to navigate that tradeoff well.

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