Talk:Submarine

Boat or ship?

I notice the difference between boats and ships has been questioned a few times in the archive: For an intriguing answer to the question, try this video on youtube, which claims the USN's definition is that boats lean inward when they turn, while ships lean outward. Do submarines lean when they turn? Xyl 54 (talk) 00:57, 5 September 2021 (UTC)

They should lean inward, normally. On a submerged vessel, the centre of pressure is fixed relative to the hull. For static roll stability, it must be above the centre of mass. If we assume that the hull is a long ellipsoid (or some other cylindrically symmetric shape), the centre of pressure is at the axis of symmetry, so the centre of mass must be below that. During a turn, the centripetal force acts on the centre of lateral resistance, at the axis of symmetry, above the centre of mass, so it must roll in. The occupants should barely notice the roll, just as those in an aeroplane don't feel it banking in a turn. If there is a fin on the top of the submarine, the centre of lateral resistance is even higher, making the roll stronger.

The suggested definition is a bit questionable though: almost every surface vessel with a simple displacement hull and a rudder or vectored thrust not too low leans outward in a turn, including many lifeboats, which nobody calls ships. It would take an extremely low centre of mass, well below the waterline, to lean inward. PiusImpavidus (talk) 19:43, 16 July 2022 (UTC)

Inadequate definition

The definition is not supported by any reliable sources. This must be fixed.

I checked Britannica, where they claim "submarine, any naval vessel that is capable of propelling itself beneath the water as well as on the water’s surface" which is dubious, as there is no obvious reason why all submarines must necessarily be naval vessels. This definition without the naval vessel requirement, would include most submersibles, as it does not give any requirement for how effective such propulsion needs to be.

Merriam-Webster:"a naval vessel designed to operate underwater" is even less discriminating.

Cambridge dictionary: "a ship that can travel underwater."

Collins: "a type of ship that can travel both above and below the surface of the sea."

Longman: "a ship, especially a military one, that can stay under water." Particularly useless as any ship can stay underwater if it sinks.

Oxford Learners: "a ship that can travel underwater."

Jane's Dictionary of naval terms: Warship able to submerge for long periods and chiefly operating below surface." also "true submarine: term sometimes applied to submarine able to operate continuously without any contact with surface for air, navigation or communication."

Saunders, 1972, Hydrodynamics in ship design, SNAME, Vol 1 page 361: "...designed to run for the greater part of their operating time on the surface... here called submersibles", and "...designed primarily for submerged operations, with surface performance secondary. They are called true submarine craft"

Accordibg to Dr. Edith A. Widder, a senior scientist at Harbor Branch Oceanographic Institution: "The difference between a submarine and a submersible is a submarine has enough power to leave port and come back to port under its own power. A submersible has very limited power reserves so it needs a mother ship that can launch it and recover it." Widder is probably not an authority on marine engineering and naval architecture, but this does appear to be common contemporary usage among the people who use submarines and submersibles, though it contradicts earlier technical usage by specialists. My opinion is that the terms have been used rather loosely for the most part, and distinguishing between a submarine and a submersible is an exercise in futility, as it depends on who and when, possibly also where.

I will research further, but if anyone else has authoritative sources, please contribute. · · · Peter Southwood ^(talk): 16:04, 22 January 2023 (UTC)

You seem to have discounted the first definition there purely for use of the word "naval." Are you conflating "naval" with "seaborne branch of the military?" There are broader uses of the term naval than that. From Hill To Shore (talk) 17:13, 22 January 2023 (UTC)

From Hill To Shore, I consider the combination "Naval vessel" to refer to a vessel operated by a seagoing branch of the military, does your experience differ? As I was trained as a naval architect and have been a naval officer, both in the dim and distant past, I am aware of the broader meaning of "naval" pertaining to ships in general, deriving from the Latin adjective navalis, but I think this specific combination really only refers to navies. Cheers, · · · Peter Southwood ^(talk): 17:50, 22 January 2023 (UTC)

I don't know if this helps (and I trust this quotation is not too long) but the following is from Concepts in Submarine Design by Roy Burcher and Louis J Rydill, published by Cambridge University Press, page 11:
"... the differentiation sometimes made between submersibles and submarines, are contentious and can be confusing. The argument for differentiating is that it was not until the advent of nuclear propulsion, and the associated atmospheric control capability enabling a boat to operate entirely submerged throughout a patrol of several months duration, that the ‘true’ submarine had arrived. The complementary picture of the submersible is that it describes a boat obliged to operate mainly on or near the sea surface – in order to have access to the atmosphere for oxygen for breathing and for combustion propulsion engines – and which submerges periodically when on patrol for the purposes of concealment, undertaking an attack with torpedoes or avoiding attack on itself."
The authors go on to explain that that they choose to use "submarine" throughout the book and leave "submersible" to commercial operators. They point out that all submarines are submersible and that a "sharp differentiation is misleading". ThoughtIdRetired (talk) 19:46, 22 January 2023 (UTC)

A submarine is not necessarily a naval vessel. There have been merchant submarines, such as the German submarine Deutschland. Mjroots (talk) 06:59, 23 January 2023 (UTC)

Semi-protected edit request on 20 June 2023

There's one instance of a misspelling of stability, you can find it by searching for 'stab'. FormalityInducer (talk) 21:23, 20 June 2023 (UTC)

Page search for "stab" brings nada. - FlightTime (open channel) 21:32, 20 June 2023 (UTC)

 Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. I couldn't find it either, which isn't what edit requests are for. Please be more specific, per.the instructions. BilCat (talk) 22:17, 20 June 2023 (UTC)

Article on military submarine is needed

We hava a ton of articles abou various subtypes of military sumarines (ex. Attack submarine, Ballistic missile submarine, Cruise missile submarine, and Nuclear submarine), but no main article. This article (about submarines) covers both military and civilian uses. Interesting oversight. Right now military submarine is just a redirect here. _{Piotr Konieczny aka Prokonsul Piotrus| reply here} 05:54, 6 March 2024 (UTC)

It is not clear to me why an additional generic article for military types is needed. What sort of material would be included that is not already here? Did you have in mind something like military aircraft compared with aircraft? - Davidships (talk) 11:28, 30 October 2024 (UTC)

No mention of Narcís Monturiol?

The first modern submarine was invented by the Catalan Narcís Monturiol in 1864, with many successful tests and several published studies. This submarine was the first with a steam boiler and used as fuel a pot of magnesium peroxide, zinc and potassium chlorate (whose chemical reaction provided oxygen both for combustion and for the crew). In addition, it had compartments that could be filled and emptied of water. It is incredible that this article does not say anything about that. It seems that those who say that Wikipedia is not reliable are not wrong.--Beticat (talk) 18:29, 15 October 2024 (UTC)

See the "1863–1904" subsection under History. Regards, -Fnlayson (talk) 18:33, 15 October 2024 (UTC)