Bajansailor
regular
Reged: 27/12/2004
Posts: 2254
Loc: Barbados (East coast)
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Here (at the link below) is a powerpoint presentation showing a few interesting cases of cargo damage as a result of bad weather - and also some photos that show that us as people are not 100% infallible, and that we do make mistakes occasionally.....
Have a look at http://www.its-insurance.com
and scroll down to the bottom of the page to 'Freight Forwarder's Lament'. You have to download the Powerpoint presentation, which is 2.9MB, but it is well worth the wait!
Have a look also at the link earlier on this web-page re the M/V 'Mighty Servant' - in similar fashion to that car carrier that capsized off Alaska last year, it looks like someone didnt do their ballasting and stability calculations properly.....
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If you are going on holiday to Barbados, google us for the lowdown on places to stay and things to do, or have a look at http://www.doyleguides.com/barbados.html
for an impartial yachtsman's guide.
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jamesmar
regular
Reged: 23/10/2004
Posts: 1000
Loc: Me ..west of Scotland..Boat Gr...
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How are these containers secured on board ship? I know that they are clipped on to trailers when they are being transported on land,but they seem to have nothing holding them together on board ship.Looking at the pics surely they would have a better chance of surviving if they were clamped together?
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Mirelle
regular
Reged: 30/11/2002
Posts: 4515
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Oh, let me assure you that they are not only twistlocked together but lashed down to the ship's hatch covers and, on larger ships, lashing bridges, with big steel rods and huge bottlescrews - 50 tons breaking strain is a common number.
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jamesmar
regular
Reged: 23/10/2004
Posts: 1000
Loc: Me ..west of Scotland..Boat Gr...
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Thanks for that info...it's reassuring to know that they rely on more than gravity to hold them on!! Still...it's a bit alarming that they can fall off despite the fixings.
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Mirelle
regular
Reged: 30/11/2002
Posts: 4515
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Beware! I can get rather technical here! (I operate big containerships).
The ship (these days, t'was not ever thus!) is built with a Class Society approved lashing plan. This lives in the loading computer, and, knowing how the ship is loaded, her ballast and fuel condition on departure and arrival (different, because fuel is burned) and the weight of each box on board, it calculates what the maximum "g" forces acting on each corner of each box will be, and announces what lashings are required to resist them. If the result of the sum is an absurdity the lashing computer won't let you do it.
So far, so pretty good; millions of containers travel across the world's oceans and arrive in one piece.
However, here are some things that go wrong:
1. Lashing gear may be defective (suspected as a cause for a series of losses overboard last year)
2. The ship may part discharge cargo at one port and, having thus become more stable, i.e. "stiffer", sail for another without revising the lashing plan. The "g" forces are now larger and may exceed the parameters...this is an Old Chestnut which old lags like me like to frighten young Chief Officers with...
3. Another suspected problem is that very large ships, with "barge shaped" hulls due to keeping the draft down to 14.5 metres may experience a sort of whiplash effect and actually "flick" stacks of boxes at the ends of the ship overboard with sudden huge "g" forces as the rather bendy hull structure recoils in big seas.
4. Then, of course, we have "parametric rolling"... hours of fun, but basically on some headings and in some sea conditions the ship can develop a "death roll" - rather like a sailing dinghy going downwind with the kicker slack - and roll further and further until, once again, the predicted "g" forces are exceeded.
Hope this helps!
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PyroJames
regular
Reged: 09/08/2002
Posts: 996
Loc: Cambridge
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And then there is misdeclared overweight cargo....
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