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Comment by komali2 | Hacker News Reader

>violently depressurized

If we get to use this when a plane's window breaks, what do we say about the Byford Dolphin incident?

> Hellevik, being exposed to the highest pressure gradient and in the process of moving to secure the inner door, was forced through the 60 centimetres (24 in) diameter opening created by the jammed interior trunk door by escaping air and violently dismembered, including bisection of his thoracoabdominal cavity, which further resulted in expulsion of all of the internal organs of his chest and abdomen, except the trachea and a section of small intestine, and of the thoracic spine. These were projected some distance, one section later being found 10 metres (30 ft) vertically above the exterior pressure door.

We're nearing the ceiling of available acronyms with "violent." I guess "catastrophic" could apply?

https://en.wikipedia.org/wiki/Byford_Dolphin#Diving_bell_acc...

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Diving has pressure differentials of potentially hundreds or thousands of atmospheres.

Flying has a absolute ceiling on the pressure differential of one single atmosphere - and you have to be in space to get it.

This means that an airplane depressurization event can exert a maximum of around 14 PSI. A diving depressurization event at 100 feet is 50 PSI.

EDIT: Re-reading your comment, I'm helping prove your point. So, there's that. :D

-Hundreds or thousands may be exaggerating a bit; IIRC the deepest commercial dive took place at some 600m/2000ft/60bar/850psi or so.

In the Buford Dolphin accident, the pressure differential was 9 bar/130psi.

Well, considering that most airlines operate at around 5-8psi (to reduce stress on the pressure vessel), I could argue that hundreds is still a valid measure.

But that would just being pedantic; it is an exaggeration.

> Diving has pressure differentials of potentially hundreds or thousands of atmospheres.

That's not true.

100 atmospheres is about 1000 meters.

~300 meters (~30 atmospheres) is the world records reached with Scuba equpment.

An ADS got a navy diver down to ~2000 feet (60 atmospheres).

And the deepest a human has gone in a submersible vehicle is 35,858 which only barely clears 1000 atmospheres (~1060).

14,000lb per sq inch, good god engineers are cool.

>helping prove your point

Not necessarily! I thought the route you were going down was that, relatively speaking, this was near the "maximum decompression threshold" of the context - airplanes. As in, "it doesn't really get more 'violent' than this for airplanes, so violent is the right word."

Thanks for giving me more diving nightmares though lol

Or, relatively speaking, the Aloha Airlines with fuselage damage https://en.wikipedia.org/wiki/Aloha_Airlines_Flight_243

Well, that's something I wish I didn't read this morning on HN. Did he.. survive?

The fourth diver was dismembered and mutilated by the blast forcing him out through the partially blocked doorway and would have died instantly

No!

> Did he.. survive?

Well, let's see:

    √ "violently dismembered"
    √ "bisection of his thoracoabdominal cavity" (i.e, body cut in half)
    √ "expulsion of all of the internal organs"

Spoiler alert: no. All four divers were killed, along with one of the tenders outside the diving bell.

You aren't living too long with your internal organs "explosively" removed from your chest. From the wikipedia article:

>Hellevik was about to close the door between the chamber system and the trunk when the chamber explosively decompressed from a pressure of nine atmospheres to one atmosphere. One of the tenders, 32-year-old William Crammond of Great Britain, and all four of the divers were killed instantly; the other tender, Saunders, was severely injured.[10]

According to wikipedia, the difference between explosive/violent decrompression and rapid decompression is if the air is able to safely exit the lungs. On an aircraft that means that decompression that takes less than half a second (or a tenth of a second depending on the pressure differential).

https://en.wikipedia.org/wiki/Uncontrolled_decompression#Exp...

>acronyms

adjectives?

Synonyms! I think he's looking for different words with a similar/same meaning

Both works, but I did mean adjectives!

Sidenote, I've noticed a lot of "wrong word" choices when I read through my posts here. There's no reason for it as far as I can tell... native english speaker, usually posting with a keyboard, hell I have a creative writing degree.

But I keep catching slipups like that. Super weird.

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