Comment by lb1lf | Hacker News Reader

Comment by lb1lf | Hacker News Reader

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-I've done this in simulator a few dozen times (mandatory training for anyone boarding a helicopter for going offshore, refresher courses every four years.)

It is difficult enough in the simulator - which, as you say, simplify matters immensely over an actual crash:

a) The pool with the simulator is well lit. Many places, it is even heated, so you don't get the added stress of being lowered into icy cold water.

b) Each participant has a dedicated rescue diver sitting opposite him, ready to assist at any sign of trouble.

c) The simulator is lowered into the water in a controlled fashion, without any jolts.

d) There's only one seat by each window, so you don't have to first help your mate out, then exit yourself.

Incidentally, I've found it is much easier to get out after the cabin is inverted - your buoyancy makes you pop from your seat like a cork the moment you open the harness; being inverted, you are being pushed towards your seat, and all you need to do is to pop out the window, grab the opening with one hand, undo the buckle with the other and pull yourself out. Much simpler when your buoyancy works with you than against you.

During my last refresher, we asked whether we could make it a bit more realistic by putting out the lights and leaving a few newspapers and such in the cabin (for floating around once it filled with water, further disorienting you.)

We were told in no uncertain terms that wouldn't happen; it was deemed too risky for the rescue divers - who were fully kitted out with oxygen an'all.

Note to self: I do not want to be in a helicopter emergency landing on water. Ever.

I did about ~30 offshore helicopter flights to Sealand (~20km offshore UK) in 1999-2002 and never did a simulator. I don't even remember a preflight brief. I'm glad I didn't know how dangerous it was at the time. Of course, given that we weren't wearing exposure suits or anything, it would probably have been quick death vs. slower death in any accident.

Mea culpa, I should have added '...in my jurisdiction'. (Norway)

I haven't looked into the legal background, but my guess is that offshore workers' unions have lobbied for it - and, most likely, it only applies to flights to/from sites operated by major players.

Also, some countries refuse to recognize training from other countries (Brazil, I am looking at you!) - so you end up having to do the same basic training in [n] jurisdictions, having [n] different certificates on you at all times, all with their individual refresher requirements...

OT but why were you going out to sealand? Did you have server racks there?

Yes

Forgive me if this is a dumb question, as I have no experience with helicopters or scuba diving. But wouldn't it be easier and dramatically safer to just keep emergency scuba equipment onboard that might give you ~15 minutes or so of breathable air to give you time to deal with the situation? Full scuba tanks might be impractical, but something with a small supply of air probably wouldn't take up that much space.

It is not a dumb question.

Depending on where you're embarking from, equipment like this may already be available - though not with a 15-minute supply, more like a minute, perhaps.

When I've flown from Norway in latter years, our survival suits (worn throughout the flight) have been equipped with a rebreather device - you bite down on a mouthpiece connected to a plastic bag integrated in your suit, and as you exhale into the plastic bag, you can then draw the same air back in again - no CO2 scrubbing. The mouthpiece is equipped with a valve which lets you breathe normally while above water; you then close it as you are submerged and breathe into the bag until you've reached the surface again.

The idea being that this will do for a minute or two - and in that minute, you're either out of the wreck or dead.

(I've asked the simulator instructor how long we spend underwater - he shrugged and said 'On average, six to fifteen seconds' - so a minute is a long, long time.)

If you’re not scuba trained this is going to be pretty useless. Breathing from an oxygen tank whilst being unable to see (no mask), and constantly and steadily breathing as you descend and ascend take training. Not to mention the shock of the cold water and having to remember all this scuba training info. I think it would be useless for anyone that’s not an expert scuba diver, better to improve the harness so that passengers can actually release themselves.

If you can barely remove your harness and get out, odds are you won’t be able to locate scuba equipment and use it

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