The Korean Ferry SInking

In the BBC’s report of the ongoing Korean ferry sinking, this line stood out (in the analysis, off to the side):

The speed with which it flipped over and sank is a major concern.

This is a well-known problem with car ferries.  In order to make them economical you need to have fairly open car decks without any watertight bulkheads dividing the decks into compartments as you would on any other type of vessel.  You want all your cars to be able to drive unhindered into what is effectively a large floating car park and then drive off the other end when the ferry reaches its destination.  The problem with this is that water sloshing about on an open deck makes a vessel extremely unstable.

Back in the late ’90s I found myself stuck at home in Pembroke with a computer but no internet (it wasn’t widespread in homes back then) and an assignment to write for my engineering degree on engineering risks.  I had very little material to base an essay on, but there was a stack of old New Scientist magazines of my sister’s lying about, and one of them (dated August 1990) had this article in (subscription required), which is introduced as follows:

The risks of ferry travel: Many car ferries are built with a fatal design flaw. If the vehicle decks flood, the ferries are likely to capsize rapidly.

The article said that an inch of water covering a car deck was enough to cause a ferry to capsize, due to the enormous momentum of the sloshing action.  An inch isn’t much when you have the sea pouring in.

This is why ferries tend to sink so quickly, with both the Herald of Free Enterprise (March 1987) and Estonia (September 1994) disasters being the two that I remember happening; the first because it involved a lot of Brits in what seemed to be a spate of home-grown disasters (the Kings Cross Fire in November 1987, Piper Alpha in July 1988, and the Marchioness in August 1989) and the second because of the harrowing accounts of the ship listing severely before disappearing into the freezing Baltic Sea.  I’ve since been on a ferry from Finland to Tallinn, and ending up in the water doesn’t bear thinking about.

The New Scientist article has stuck in my mind since, probably because I had to write an essay on it in the absence of any other source material.  I got a good mark by the way, mainly because I actually wrote a good essay, but the lecturer did remark that my basis was somewhat limited!  The other aspect of ferries mentioned in the article which contributed to their poor safety record – on some measures, ferry travel is the most dangerous in the world – was that the operators tend to get complacent.  You can imagine, doing the same, normally short, route day after day would breed complacency among the crew in terms of safety equipment inspections, evacuation drills, etc.  Also, a lot of ferries, especially in the developing world, are operating on a shoestring budget whose owners aren’t much interested in spending money on things like maintenance and inspections.  Add in poor training and experience of crew and you have, well, a recipe for disaster.

For all of these reasons, underpinned by the fatal design flaw described in New Scientist, I fear ferry disasters – like air crashes – will always be with us.

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18 Responses to The Korean Ferry SInking

  1. TNA says:

    “on some measures, ferry travel is the most dangerous in the world”

    Worse than helicopters, you reckon? I dunno…..

    Ordinarily, “CEO died” in Google results in a page of helicopter crash stories. Interestingly today it seems to be suicides. The Illuminati have been busy this month.

  2. Tim Newman says:

    Worse than helicopters, you reckon?

    It depends on the measurement. I shouldn’t actually have said dangerous, the article itself used “deadly”, which is a bit different: the former implies risk, the latter absolute numbers.

    From memory, there are usually two measures used in transport safety: “deaths per passenger mile traveled”, and “deaths per completed passenger journey”. IIRC, cars are the leading mode of transport in the former, and I think the article cited ferry travel as the leading mode for the latter.

    I think what saves helicopters – which are undoubtedly dangerous – from heading the rankings is they don’t carry many people. 300 people are missing from this Korean ferry, you’d need an awful lot of helicopters to crash to reach that number. Coaches and trains tend to have multiple casualties as well, and crash far more often than planes.

    Ordinarily, “CEO died” in Google results in a page of helicopter crash stories.

    Yes, there was a period in Russia when being invited to take a helicopter flight was a very bad idea if you were the head of some major enterprise. But most of them elsewhere are just straightforward crashes, regardless of what the dimwitted conspiracy theorists think every time one goes down with somebody important on board.

  3. dearieme says:

    You must know something about the problems that can be caused by sloshing in ill-designed distillation columns, Tim. Or not your patch?

  4. Tim Newman says:

    Nope: as you say, not my patch. I’m very much an upstream man, exploration and production. Separators and slug catchers are about as big and complicated as it gets, unless I poke my nose into LNG which I’ve not done for a while. Interesting that sloshing is a problem in distillation columns though.

  5. TNA says:

    Yep, I can see how the two reporting methods would result in those two transport types.

    Helicopters just feel so much more risky to me. Which is why I don’t use them.

    The irony is I’m a motorcyclist. So I suppose that make me the travel equivalent of a chicken-eating pescatarian.

  6. dearieme says:

    I suppose the lesson is that you shouldn’t use car ferries unless you are accompanying your car.

  7. Bloke in Germany says:

    What are the stats for deaths from car crashes on car ferries?

  8. Aussie Pride says:

    Good post Tim, although I agree with TNA that you have to be careful with words when making these comparison.

    We had same compulsory subject in my Mech Eng degree – I can’t remember what I did as my case study but it was an interesting topic that looked at disparate Engineering disasters ranging from the Tecoma Narrows Bridge to the Comet jet airliner.

    One of the lessons I took away from that subject is it’s a good idea to STFU about causes when something bad happens until you’ve had a chance to get all the facts together, something that’s being missed in the current discussions about MH370.

    These days I dabble in the IT industry I’m always amazed at the sector’s total lack of understanding about risk, I’m fascinated at the whole Internet of Things meme which involves plugging everything from oil rigs and jet engines to toasters and fridges onto the less than reliable or secure internet.

    At least mariners, like engineers, understand that minor cockups can have spectacularly lethal consequences.

    BTW, that late 1980s period in the UK was very interesting. I was living there at the time and every week there seemed to be another disaster. The ones I particularly remember are Lockerbie and Clapham Junction, the latter because my then girlfriend and now wife was in the train immediately following.

  9. TNA says:

    By the way, March is the time the English Channel is at its coldest. Don’t be on a sinking cross-Channel ferry around that time.

    I skippered a yacht from Plymouth to Le Havre a couple of years ago. My safety briefing on man overboard procedure was that we’d definitely turn around and look for the body; you’ll only last 2 to 3 minutes.

  10. Tim Newman says:

    Helicopters just feel so much more risky to me. Which is why I don’t use them.

    Add in Nigerian pilots and maintenance and you’ll know how I felt!

  11. John B says:

    The sinking of the Herald of Free Enterprise and Estonia had different causes. The former involved the ‘sloshing effect’ of a relatively small amount of water taken onto the car deck exacerbated by a sharp turn which cause the ferry to capsize almost immediately, the latter was caused by the bow door breaking off in rough seas causing the vessel to flood and sink rapidly.

    The design flaw which caused the Herald of Free Enterprise to capsize is easy to correct with central raised barriers stem to stern along the lower car decks to stop any water gaining sufficient momentum to cause capsize. I understand British ferries were retrofitted and new ferries were built incorporating this design.

    It is not clear yet what caused Korean ferry to sink, it may have hit something, but it took an hour… hardly ‘speed at which it sank’.

    The high death toll is credited to passengers being told to stay below in their cabins and lower decks, a message being repeated half an hour later.

  12. Andrew S. Mooney says:

    To Tim Newman – As an engineer with a knowledge of structures, you’ve missed off another factor to why the ship probably sank: Amazingly the Wikipedia entry for this accident lists it, in the form of the fact that the upper decks of the ship were modified by the owners to add more cabins. – 239 TONS of mass was added to the TOP of the ship, five stories above the sea.

    http://en.wikipedia.org/wiki/Sewol_disaster

    When you then factor in the fact that the vessel was very lightly loaded, and it is possible that ship could be rolled simply by making an aggressive turn using the existing rudder and thrusters.

    In that instance, who is responsible? The captain or the company that did all of the modifications and owned it? Little wonder that they want him found guilty and chucked in jail as quickly as possible.

  13. Tim Newman says:

    @ Aussie Pride,

    Good comment!

    We had same compulsory subject in my Mech Eng degree – I can’t remember what I did as my case study but it was an interesting topic that looked at disparate Engineering disasters ranging from the Tecoma Narrows Bridge to the Comet jet airliner.

    Yup, we did those too.

    One of the lessons I took away from that subject is it’s a good idea to STFU about causes when something bad happens until you’ve had a chance to get all the facts together, something that’s being missed in the current discussions about MH370.

    Agreed, and I made that point here regarding the Macondo incident.

    These days I dabble in the IT industry I’m always amazed at the sector’s total lack of understanding about risk, I’m fascinated at the whole Internet of Things meme which involves plugging everything from oil rigs and jet engines to toasters and fridges onto the less than reliable or secure internet.

    I agree that plugging everything into the internet is daft, and looks mostly like a solution in search of a problem. But the oil rigs are tied into networks which are supposedly extremely secure, not the ordinary internet. I once tried to install wireless temperature monitoring equipment on an installation a few years back, and found it was outlawed by the company due to cyber-security fears.

    BTW, that late 1980s period in the UK was very interesting. I was living there at the time and every week there seemed to be another disaster. The ones I particularly remember are Lockerbie and Clapham Junction, the latter because my then girlfriend and now wife was in the train immediately following.

    Yes, I’d forgotten Clapham Junction, didn’t think to include Lockerbie. Fortunately we seem to have largely learned valuable lessons from them, at least insofar as Piper Alpha, Kings Cross, and The Herald of Free Enterprise goes.

  14. Tim Newman says:

    @ John B,

    Good points, all.

    It is not clear yet what caused Korean ferry to sink, it may have hit something, but it took an hour… hardly ‘speed at which it sank’.

    True, but I was lazily quoting the BBC.

    The high death toll is credited to passengers being told to stay below in their cabins and lower decks, a message being repeated half an hour later.

    That does sound like a major cock-up.

  15. Tim Newman says:

    @ Andrew S Mooney,

    Thanks for that bit of info, fascinating stuff which could well have been a major contributor to the incident escalating as it did. I’m not surprised that such modifications were made…in my experience of Korean engineering and construction, which includes some maritime stuff, the design and construction quality leave an awful lot to be desired. The key driver on a project is the construction schedule, and some of the things you see are extremely cowboyish and in some instances an utter disgrace which has gotten people killed.

    In that instance, who is responsible? The captain or the company that did all of the modifications and owned it?

    Quite. But in Russia, captains are expendable whereas vessel owners tend to be wealthy and politically connected. I suspect it’s the same in Korea, and most other places in the world.

  16. South Korea has a very nationalistic streak, and this can be a bad thing when it comes to engineering. South Korean companies can be very reluctant to buy in foreign expertise or use foreign technology, or to acknowledge that foreign expertise might be useful or in some instances better than Korean expertise. Therefore, they are not very good at learning lessons that have been learned abroad, and have to learn the same ones themselves the hard way. That’s a generalisation, of course, but there is some truth in it.

    Second thing – not particularly related. When travelling in developing countries and looking for transport options, I have read the sentence “There used to be a ferry between A and B, but this no longer runs because the ferry sank” a lot of times. Ferries in developing countries often consist of old ferries that used to run in developed countries, but which were retired because they were nearly worn out and/or they do not satisfy modern safety standards. Put these in the places where crews are less skilled and trained, and maintenance and safety standards are poor, and you are asking for trouble. Trouble duly occurs.

    I once also went for a walk around the ferry terminal in Marseilles. This has two terminals – “domestic” and “international”. Domestic is for ferries to Corsica. The building is nice. The ferries are nice (and state owned). The cars driving onto the ferries are modern cars. On the other hand, international is for ferries to Algeria. In this case the terminal was an ancient building that looked like it was about to collapse, the ferries looked like they were about to sink, and the cars driving onto the ferries were old vehicles that that had enormous amounts of stuff strapped to their roof-racks. One only needs one end of the ferry route to be in the third world for things to be lax. At least, this is the case when France is at the other end of the route.

    (I almost wrote “the cars driving onto the ferries looked like they were about to break down, but then I remembered that they were mostly Mercedes W123s, and these are well known for being indestructible and never breaking down, regardless of how old they are).

  17. Tim Newman says:

    @Michael,

    Interesting observations about ferry travel serving different customers, which I am sure is universal. The ferry between Helsinki and Tallinn was very nice, unsurprisingly.

    I agree with you about Korean nationalism setting them back. And in my experience of Korean companies, speed and costs take precedence over quality every time. Unlike the Japanese, doing a quality job is not inherent to the Korean culture. Far from it, in fact.

    …then I remembered that they were mostly Mercedes W123s, and these are well known for being indestructible and never breaking down, regardless of how old they are.

    You’ve got that right! Lebanon is the place to go to see those held together with string, rattling their way up mountain roads.

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