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You guys are tall ship masters. Your vessels are generally well understood these days but let's not forget some comparable disasters: Vasa and Mary Rose. Yes

You guys are tall ship masters. Your vessels are generally well understood these days but let's not forget some comparable disasters: Vasa and Mary Rose. Yes both are from a long time ago but both were based on top of a lot of good solid engineering but both pushed the envelope somewhat and perished. Vasa design basically forgot to sort out the various CoGs for a ship - it was top heavy. Mary Rose loss is a bit more complicated but for me water ingress via lower open gun ports, compounded by heavier loading was a possible failure scenario. I'll also recall the sinking of the Herald Of Free Enterprise - a roll on/roll off ferry that departed Zeebrugge and "rolled over" in shallow water due to the bow door being left open - ie stupidity and a lack of monitoring. That wasn't a tall ship but the same general rules apply. Those are three samples from 400 years of maritime history. The Vasa was a daft design from the outset (meta vs cog), Mary Rose a daft refit after 30 years of service (it was OK for 30 years and then wasn't) and Herald was basically abused by her crew and lacked monitoring. Now submarines are pretty new. We do have a fairly long history of making pressure hulls from steel and some other materials but they all build upon earlier designs and they have all been tested with a lot of loss of life for failed designs - the history of submarines is pretty sad. I gather that all very deep sea hulls are basically spherical. The Titan's pressure hull was made of carbon fibre which I gather no one else has used like that. As well as a novel material its shape was elongated to allow more passengers - that's two changes. Finally we also have a viewing port at the front that was actually tested but never rated for 4000m. No one really knows what happens to carbon fibre pressure hulls when they go from one atmosphere to 180 and back again, repeatedly, then they are picked up out of the water - more stress and strain. Also, no one really knows what happens at the interface of a "window" to carbon fibre at 180 atmospheres. There are lots more questions to be answered but frankly I see a company trying to run a submarine with DevOps attitude (move fast and break things) rather than proper maritime grade engineering. At 180 times atmospheric pressure, you die within seconds. No ifs and no buts. I absolutely stand with you guys in insisting on standards for this sort of thing. It isn't the same as running up Everest or going into space. Deep sea is way, way more dangerous.

dragonwriter 3y ago
> The Titan's pressure hull was made of carbon fibre which I gather no one else has used like that. Discount, too-old-for-aircraft-use carbon fiber, apparently: https://www.insider.com/oceangate-ceo-said-titan-made-old-material-bought-boeing-report-2023-6 https://www.insider.com/oceangate-ceo-said-titan-made-old-ma...
cycomanic 3y ago
I recommend watching the interview with Cameron. You say deep sea diving history is pretty sad, well actually there have been amazingly few incidents (and even fewer deaths) in the history of deep sea diving. And the engineering challenges are pretty well understood. They were just ignored in this case.
- brandall10 3y ago
  Cameron went so far to say the design mythology itself was inherently flawed at the principal designed of his own vehicle. That said, his vehicle wasn’t certified either, rationale being it wouldn’t carry passengers.
elcomet 3y ago
> It isn't the same as running up Everest or going into space. Deep sea is way, way more dangerous That doesn't seem right to me. Deep sea and space seem equally dangerous
- gerdesj 3y ago
  Space has different issues but basically -1 atmosphere vs 180 atmospheres is a constant. 180 atmospheres is absolutely brutal. Without any real justification, I invite you to imagine an elephant pirouetting on top of your skull. Hmmm, nice image, does it stack up: 180 atmos is 186 kg/cm^2 according to random online calculator. That's 2645 psi in old money, according to Google calc. An adult african elephant is about 5-6 tonnes according to several sites (max 6.8 tonnes). So 6000/186 = 32 cm^2. root 32 is about 5.7cm. I really did pluck the elephant thing out of the air and it does seem to work out (please check my 'rithmetic). Imagine that every 5.7cm^2 of your body/vessel/submarine has an adult african elephant's weight bearing on it. Now in space we have a bit of a problem with keeping everything in, instead of out but we can lower the internal atmospheric pressure and up the oxygen content (fire risk - procedures!) and other tricks and we have to scrub the CO2 (and so below surface). We also have to worry about very, very fast moving anything, radiation and other issues. But in space you do not have an elephant's weight crushing each 2.5" square of your body, all the time! That's why deep sea is far more dangerous than space (which is also very dangerous).
  - Ajedi32 3y ago
    With current technology the most dangerous part about space isn't being in space, it's getting there (and back). So far, nobody has ever died just sitting in orbit. (Closest was the Soyuz 11[1] and even that was a result of an incident during the re-entry process.) [1]: https://en.wikipedia.org/wiki/Soyuz_11#Re-entry_and_death https://en.wikipedia.org/wiki/Soyuz_11#Re-entry_and_death
bradknowles 3y ago
With respect, the "DevOps attitude" is not "move fast and break things". That's the Facebook attitude. DevOps is, in part, about using repeatable methods of automation and extensive testing throughout the software development lifecycle to try and make sure that the software you deliver in production will do exactly what it should do and nothing else, and so long as it is properly designed, should be able to withstand significant scaling stress but just getting slower and slower but not less reliable. From what I can tell regarding the Titan incident, there was no part of a proper DevOps mindset or approach that those people adopted. They people in charge were just damn stupid cowboys out to make a fast Buck from people who were too stupid to know how much in danger they were of losing their lives.
- gerdesj 3y ago
  Soz mate, I was a little enthusiastic in making my point and I picked on an easy target. I'm well aware how DevOps works.

dragonwriter 3y ago

> The Titan's pressure hull was made of carbon fibre which I gather no one else has used like that. Discount, too-old-for-aircraft-use carbon fiber, apparently: https://www.insider.com/oceangate-ceo-said-titan-made-old-material-bought-boeing-report-2023-6 https://www.insider.com/oceangate-ceo-said-titan-made-old-ma...

cycomanic 3y ago

I recommend watching the interview with Cameron. You say deep sea diving history is pretty sad, well actually there have been amazingly few incidents (and even fewer deaths) in the history of deep sea diving. And the engineering challenges are pretty well understood. They were just ignored in this case.

brandall10 3y ago
Cameron went so far to say the design mythology itself was inherently flawed at the principal designed of his own vehicle. That said, his vehicle wasn’t certified either, rationale being it wouldn’t carry passengers.

elcomet 3y ago

> It isn't the same as running up Everest or going into space. Deep sea is way, way more dangerous That doesn't seem right to me. Deep sea and space seem equally dangerous

gerdesj 3y ago
Space has different issues but basically -1 atmosphere vs 180 atmospheres is a constant. 180 atmospheres is absolutely brutal. Without any real justification, I invite you to imagine an elephant pirouetting on top of your skull. Hmmm, nice image, does it stack up: 180 atmos is 186 kg/cm^2 according to random online calculator. That's 2645 psi in old money, according to Google calc. An adult african elephant is about 5-6 tonnes according to several sites (max 6.8 tonnes). So 6000/186 = 32 cm^2. root 32 is about 5.7cm. I really did pluck the elephant thing out of the air and it does seem to work out (please check my 'rithmetic). Imagine that every 5.7cm^2 of your body/vessel/submarine has an adult african elephant's weight bearing on it. Now in space we have a bit of a problem with keeping everything in, instead of out but we can lower the internal atmospheric pressure and up the oxygen content (fire risk - procedures!) and other tricks and we have to scrub the CO2 (and so below surface). We also have to worry about very, very fast moving anything, radiation and other issues. But in space you do not have an elephant's weight crushing each 2.5" square of your body, all the time! That's why deep sea is far more dangerous than space (which is also very dangerous).
- Ajedi32 3y ago
  With current technology the most dangerous part about space isn't being in space, it's getting there (and back). So far, nobody has ever died just sitting in orbit. (Closest was the Soyuz 11[1] and even that was a result of an incident during the re-entry process.) [1]: https://en.wikipedia.org/wiki/Soyuz_11#Re-entry_and_death https://en.wikipedia.org/wiki/Soyuz_11#Re-entry_and_death

bradknowles 3y ago

With respect, the "DevOps attitude" is not "move fast and break things". That's the Facebook attitude. DevOps is, in part, about using repeatable methods of automation and extensive testing throughout the software development lifecycle to try and make sure that the software you deliver in production will do exactly what it should do and nothing else, and so long as it is properly designed, should be able to withstand significant scaling stress but just getting slower and slower but not less reliable. From what I can tell regarding the Titan incident, there was no part of a proper DevOps mindset or approach that those people adopted. They people in charge were just damn stupid cowboys out to make a fast Buck from people who were too stupid to know how much in danger they were of losing their lives.

gerdesj 3y ago
Soz mate, I was a little enthusiastic in making my point and I picked on an easy target. I'm well aware how DevOps works.