Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [ships]

35 questions
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Why would you launch a large ship by dropping it sideways?

I'm referring to the process shown in this video: https://youtu.be/Quyr5R1Rbfw?t=20 Or this image from Wikipedia: In it, a large warship is launched into the water by essentially dropping it sideways down some ramps and off of a pier. The ship…
aroth
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Can a riverboat tack upriver?

Note: This question originally appeared on the Physics site (see here) and was closed for being off-topic. Whoops! If ships at sea can tack in a zigzaggy pattern by converting backwards force from the wind (using the sail) into sideways force, then…
Palbitt
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What kind of ship is this?

I've recently been on Rügen and I have seen this: Does anybody have an idea what this is? (To give Google a chance: A ship with four "towers" made out of steel on it. They looks a bit like high-voltage electrical towers.)
Martin Thoma
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How to design a reinforced concrete ship keel?

I am building a small ship (or very large sailboat) that will have a concrete ballast at the base of the keel. I am looking to increase the weight of the concrete (lb/ft3), but I also want to maximize the impact resistance of the concrete to resist…
Escoce
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How does a cable-laying ship retrieve a partly-laid cable?

I was reading an article in the press this week about a project to lay an undersea cable across the Tasman Sea. The ship had had to return to port for repairs and return to complete the job later. This got me wondering: how does the ship secure the…
Airsick
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Disposition of the generators on the shipwrecked Costa Concordia

Recently I have been reading about the shipwreck of the Costa Concordia, unfortunately what I read is not online, so I have no links, but it raised a lot of questions. A rock hit by the ship tore a 50-metre gash which cause the flooding of 3 water…
FluidCode
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Why one big cargo ship is more efficient than 10 or 100 smaller ships?

Given the fact that small container ships are easier to manufacture than big container ships.. then why is it considered better to build bigger ships instead of many smaller ships? And to see why manufacturing is easier at smaller scale - consider…
AIon
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How are ships stacked ontop of other ships?

As shown at this skeptics SE post, there are ships that carry other ships as cargo, etc... My question: how are the ships stacked onto the flat bed ship? Is there some kind of specialized crane that is able to lift the smaller ships (seems like an…
Daddy Kropotkin
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Computation of the moment of restoring forces for a floating vessel

Some slides associated to the book Handbook of Marine Craft Hydrodynamics and Motion Control (2021 edition) are provided by the author of the book here. At page 12 of the slides for Chapter 4, the moment due to the restoration forces (gravity,…
Lucen
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How to move a stuck 400m cargo ship?

I am definitely not the captain of the Evergreen what is currently stuck in the Suez Canal: https://www.google.com/search?q=Evergreen+Suez+Canal But from an engineering point of view, what would be the best method to move this cargo ship, back to…
SutoTi
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Why are Chinese aircraft carriers conventionally powered?

China has nuclear-powered submarines, which means China is able to manufacture portable nuclear power-plants. Then, why is the latest Chinese aircraft carrier Shandong conventionally powered?
user366312
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Longtitudinal Centre of Gravity for Ship Cargo

I did a Civil Engineering course some years ago and this question from my textbook, I have found what seems impossible to get the correct answer of 46.2 m for. By putting this question up I am hoping that I will be able to come to a conclusion on…
Rob Wilkinson
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What are the 'poles' off the side off this aircraft carrier's flight deck?

Looking at a model of the HMS Ark Royal I found myself intrigued by the prominent 'poles' lining the flight deck. Some investigation on Google reveals that they can apparently be lowered to lay horizontally, presumably to keep them out of the way of…
Loid Thanead
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Regarding the ITTC Guidelines for Ship CFD applications

I was reading through the ITTC – Recommended Procedures and Guidelines - Practical Guidelines for Ship CFD Applications (https://ittc.info/media/4196/75-03-02-03.pdf) document and this little thing kept me thinking. In page 9 the distance y of the…
ASPVL
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Thrust generated by a ship

While reading about airplane engines on the internet, it is common to find figures of their thrust, in kilo Newton. However, in the case of ships and naval vessels, when talking about the engine, the only parameter mentioned is the horsepower of the…
Harsha
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