Denizens of the Straight Dope, hail and well met.
Here is a link to a modern sideways ship launching: Massive Sideways Ship Launch | PropTalk
Here is a link to the Great Eastern: SS Great Eastern - Wikipedia.
The Great Eastern was by far the largest ship of her time and she was launched sideways. My GQ is: is this the first instance of a sideways launch? I have done some web searching and can’t find anything earlier.
Zuer-coli
I wonder if a ship going into the water at too steep an angle will put too much strain on the middle - the buoyant force trying to basically fold the ship by lifting the front half to a different angle than the back half as it goes down the slide. But then I think that the ship must experience a similar strain hitting high waves… Perhaps, too, the problem is that it may stop sliding while the stern is still hung up on the slide.
I have seen many a video of a sideways launch. It is not uncommon. Some disadvantages, creates a very large wave. Also the ship is more or less dropped into the water. So size becomes an issue. but it is cheaper to build the launching platform.
No, SS Great Eastern wasn’t the first.
It might have been the first of the great steel ships to be launched sideways, as the waterway nearby wasn’t suitable for stern first launch. It was always cheaper, in terms of resources required (not consumed… available for reuse afterward !), to launch stern first, but SS Great Eastern was built beside the river near London.
Here’s a ship being launched sideways in 1751 - Duc de Bourgogne at Rochefort on 20 October 1751.
I’ve only seen sideways and then a ship in a dry-dock which is either submerged if above the water line, or, flooded if below the water line. My WAG is similar to the other poster about proving a more or less even load on the keel of the ship as well as if you have a real big ship you’ll need a lot of space to slide it out. And, part of that ship will settle into the water while the other part is on the dry dock, I can see this being problematic and having the ship at an extreme angle.
Yeah dry dock or sliding it sideways into the water appears to be it for large boats and ships.
So it’s labelled, but looks ambiguous at best to me. There seem to be conventional (perpendicular to shore) launch ways to the right. I haven’t seen further description of why this is labeled a side launch, by somebody on Wikipedia, which is of course often the issue with Wikipedia.
That said there are text references to side launching in the 18th century. For example “The Oxford Handbook of Marine Archaeology” mentions a “side launch slipway” found in excavations of the 18th century Stephen Steward shipyard in Maryland.
However another possible confusion about early ‘side’ launching is the so called Essex side launch practiced by yards along that river in Massachusetts also back at least as far as the 18th century. In that method the ship is on a launch way perpendicular to shore, but tips sideways as it moves down the ways. See video of a recent one. It’s hard to say if references to pre 19th century side launches refer to something like this method (which the 1751 illustration also might be) or a launch way actually parallel to shore as is generally understood in 19th century-onward meaning of ‘side launch’.
The Great Iron Ship, by Dugan, which I read way back in my boyhood, says Great Eastern was the first.
a reI got busy with other projects and haven’t gotten back here in some little time, The book “The Great Iron Ship” by James Dugan Copyright 1953 is in my personal library. The book engendered my inquiry.
On page 4, the first full paragraph, The second sentence says in part: “The ship was constructed of thirty thousand iron plates…”
On Page 7, the first full paragraph, the first sentence says in part: “Early in construction the price of iron plate increased…”
Also on page 7, in the partial paragraph that starts the page. the last sentence says: “The Great Eastern was to be launched sideways, a scheme then contrary to all precepts of large shipbuilding, and one that which drew many warnings of failure.” (Quoted under fair usage.)
A re-read of the first 18 pages does not reveal any statements about Great Eastern being the first ship to be launched side-ways. This is what prompted my OP.
Thank you all for your kind contributions.
Zuer-coli