Modern Launches


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Dave Hudson

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Apr 25, 2001
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When a ship is launched today, it is little more than a completed vessel being floated out of drydock.
Why have dramatic slides into rivers and bays become a thing of the past? I know that it is very bad for the hull, but as John Maxtone-Graham said in The Only Way to Cross, it gives the ship a crash course in every condition the ship may face. IOW, if the keel wasn't sturdy enough to survive an Atlantic gale, that would become obvious at the launch instead of at sea with hundreds or thousands aboard.

Any reason why they aren't used anymore?

David
 

Joshua Gulch

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Mar 31, 2001
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David,
There's also the method of dumping them off sideways into the water, as shown in the launch of WHOI's new Atlantis: http://www.whoi.edu/home/marine/ships.html

But I agree with you that modern launches are a bit wussy. Old launches tested the vessels extremes, modern ones are easier and cheaper.

Go figure.

Josh.
 
Jul 9, 2000
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David Hudson asked; "Any reason why they aren't used anymore?"

I would think there are several good reasons for it, not the least of which is that there is so much less that could go wrong! No risk of slamming into the opposite bank, no risk of slightly underlubricated ways catching fire, less risk of some miscalculation causing something unpleasant such as what happened to the unfortunate Principess Jolanda. (She went in, rolled over and sank on the spot!) Less risk of somebody being killed as supporting timbers are knocked away such as what happened to one poor bloke when the Titanic was launched...

Building and launching from a graving dock may not be all that spectacular, but it's a lot less dicey.

Cordially,
Michael H. Standart
 
Oct 28, 2000
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Launching down ways was done because it had always been done. Early wooden shipbuilders chose "hards" for their stocks (building frames). Hards are naturally sloped toward the water. Of course, builders had to find a spot along the shore with deep water close to shore. When boats or ships were completed, gravity and a shove sent them into their natural element.

Move up to the steel age...the same builders are still constructing ships. They are using the same land facilities, so they continue with the time-honored practice. Until 1900 or so, ships were still of size that made stern launches feasible. With the growth to titanic passenger liners (like Titanic) and huge freighters, problems began to arise with the old system.

Graving docks are expensive to build and maintain. No yard could afford to have three or four to use as "building docks" as long as the world needed thousands of new ships every year. Graving docks were reserved for repairs or alterations to the underwater portions of the hull. It was economics.

Harland & Wolff had room to build two Olympic-class ships side-by-side on land. They had available only a single graving dock big enough for one ship. If they had built in the dock, then Titanic could not have been started until after Olympic's completion. The advantage of building two ships simultaneously as opposed to one at a time is obvious.

--David G. Brown
 
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