Bigger, better and cheaper?
Posted on | August 5, 2010 | No Comments
It is called crying for the moon, or more bluntly, asking for something that just isn’t going to happen. What shipowner would not like clever, more advanced ships, but also lighter, so that their engines are not pushing around enormous quantities of steel that isn’t earning them any money?
And expecting shipbuilders to scurry around designing such desirable ships, tooling up their production processes to build these light-scantling beauties, and then put a price tag on them that is actually cheaper than a vessel constructed conventionally.Pigs might also fly.
It is also a little worrying when the cause of lighter ships is taken up by somebody who owns some of the world’s biggest containerships, vessels which are built with sheerstrakes like the main armour belt on the battleship Mississippi, presumably because a bit of longitudinal strength is needed.
Who recalls a fairly disastrous period in the 1970s and 1980s whencomputer assisted design “optimised” a lot of strength out of bulk carriers, with sadly fatal results for their crews. Owners get insurance when ships are lost, so this perhaps is a pretty good reason why they should be the last people to be permitted any involvement in the strength of scantlings and discussions about the waste of steel. Over-engineering neverdrowned people in the way that under-engineering does.
If you don’t have crews big enough to properly maintain plate thickness, lightness is the last thing for which you should be striving.
But perhaps Seaspan’s Gerry Wang does have a case when he suggests that a bit more structural innovation might be very welcome. We sort of “tweak” designs, extrapolating them here and there, but they really don’t change that much. Ships are still made of mild steel, when the Boeing Dreamliner is constructed of amazing composites.
We do have the Sandwich Plate System, and one of Korea’s biggest builder incorporating some of its features into designs, which is hopeful, but it seems a slow process.
Perhaps that is just as well. More than twenty years ago I attended a lecture in London by an expert in composites who suggested that they could answer a lot of our ship-construction problems. Composites, he said could have any qualities you wanted designed into them. You wanted lightness, resistance to enormous heat, abrasion, intense cold, flexibility, rigidity, ductility? You just wrote the specification.
He told us of the huge fuel tanks that lifted the space shuttles off the deck, capable of withstanding enormous heat, terrifying cold and the shock of falling into the sea from 10 miles up, all to be wiped down and re-used. Sadly, the only people who seem to have been listening to him were yacht designers.
Perhaps it was no coincidence that a fair number of young naval architects see their future in designing a winning Americas Cup boat, rather thana revolutionary merchant ship. Surely there must be a nascent Sir Joseph Isherwood sitting at his computer, with that amazing design we have all been waiting for. All I hope is that strength and durability are high on the list of attributes.