# When did submarines become a major threat to other subs? **URL:** \ **Category:** Factual Questions\ **Created:** [March 2, 2010, 9:24pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041 "2010-03-02T21:24:21Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![davekhps](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@davekhps](https://boards.straightdope.com/u/davekhps)\ **Post date:** [March 2, 2010, 9:24pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/1 "2010-03-02T21:24:21Z")
Through World War I and II, you see surface ships and aircraft drafted/designed to fight submarines on the surface, and surface ships against submerged submarines. Today, however, subs are used to hunt other subs, both underwater the whole time. When did this transition take place? I’ve seen a few stories of WWII-era subs sinking other subs, but I always assumed (perhaps incorrectly) that those engagements were on the surface (well, at least one of the boats on the surface). My question is, when did the modern stereotypical subs-hunting-subs paradigm come into being? Late WWII, or was this purely a Cold War thing? Any naval officers back in that time write about the possibility, i.e. when was wholly-underwater warfare envisioned as likely, even inevitable? Thanks much… ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [March 2, 2010, 9:36pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/2 "2010-03-02T21:36:56Z")
With the development of homing torpedoes, most likely. Wiki says that’s late WW2 for surface ships, so their development as sub-killers would be a Cold War item. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [March 2, 2010, 9:44pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/3 "2010-03-02T21:44:50Z")
World War I and II subs were diesel electrics. They weren’t underwater boats. They were surface boats that could go underwater. Since they couldn’t run the diesels while submerged they were limited in how much time they could spend under the water. With the invention of nuke subs in the 1950s, subs were no restricted by the life of their batteries with respect to how much time they could stay submerged. Modern subs can stay down for months on end. This led to the underwater cat and mouse games that modern subs play. Surface, land, and air forces do still play a major role in sub hunting. It’s just that now you’ve got other subs getting in on the hunting action as well. Another change that factored into this was the fact that WWI and WWII subs were faster on the surface than they were underwater. Modern subs are faster while submerged. This change in hull design started happening at the end of WWII when longer range airborne sub hunters made it unsafe for subs to stay on the surface. ---
**Author:** ![YamatoTwinkie](https://avatars.discourse-cdn.com/v4/letter/y/cc9497/32.png) [@YamatoTwinkie](https://boards.straightdope.com/u/YamatoTwinkie)\ **Post date:** [March 2, 2010, 10:23pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/4 "2010-03-02T22:23:43Z")
Per [wikipedia](http://en.wikipedia.org/wiki/HMS_Venturer_(P68)) The duel between the HMS Venturer (P68) and U-864 on 9 February 1945 was the only time in the history of naval warfare that one submarine intentionally sank another while both were submerged. ---
**Author:** ![Bayesian\_Empirimancer](https://avatars.discourse-cdn.com/v4/letter/b/6de8d8/32.png) [@Bayesian\_Empirimancer](https://boards.straightdope.com/u/Bayesian_Empirimancer)\ **Post date:** [March 2, 2010, 11:00pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/5 "2010-03-02T23:00:27Z")
I will not pretend any knowledge of this, but I have read Tom Clancy’s book, [SSN.](http://en.wikipedia.org/wiki/SSN_%28novel%29) But I think engineer\_comp\_geek’s analysis is very reasonable. The traditional limitations, requiring a snorkel, etc. are removed in modern subs. So the next best step, i would guess, is to make these subs hunt other subs. ---
**Author:** ![Icerigger](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/icerigger/32/432_2.png) [@Icerigger](https://boards.straightdope.com/u/Icerigger)\ **Post date:** [March 2, 2010, 11:40pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/6 "2010-03-02T23:40:06Z")
The Royal Navy had the beginnings of a sub designed to hunt other subs way back in WW1 the **R Class**. > **[British R-class submarine](https://en.wikipedia.org/wiki/British_R_class_submarine)** > > The R-class submarines were a class of 12 small British diesel-electric submarines built for the Royal Navy during World War I, and were forerunners of the modern attack submarine, in that they were designed specifically to attack and sink enemy submarines, their battery capacity and hull shape being optimized for underwater performance. > With a submerged speed of 14 knots (26 km/h; 16 mph), the class set an underwater speed record not broken until the experimental Japanese Submarine No.71 of ... ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [March 3, 2010, 6:49am UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/7 "2010-03-03T06:49:05Z")
Also, in WWII, hunting other subs would be a _distraction_ from their primary mission, which was to starve out the other side by sinking their cargo ships. Spending time on anything other than that was contrary to orders, and to their basic purpose. Even sinking a battleship or carrier, while exciting to sub commanders, meant neglecting their basic mission. The real critical targets were oil tankers (at least in the Pacific). Note that submarines were ranked according to the _cargo tonnage_ that they had sunk. Thus USS Flasher is listed as the ‘top’ US submarine. ---
**Author:** ![YamatoTwinkie](https://avatars.discourse-cdn.com/v4/letter/y/cc9497/32.png) [@YamatoTwinkie](https://boards.straightdope.com/u/YamatoTwinkie)\ **Post date:** [March 3, 2010, 1:32pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/8 "2010-03-03T13:32:11Z")
> [@Icerigger](#): > > The Royal Navy had the beginnings of a sub designed to hunt other subs way back in WW1 the **R Class**. Those were designed for targeting surfaced subs, however. ---
**Author:** ![davekhps](https://avatars.discourse-cdn.com/v4/letter/d/a5b964/32.png) [@davekhps](https://boards.straightdope.com/u/davekhps)\ **Post date:** [March 3, 2010, 4:27pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/9 "2010-03-03T16:27:03Z")
Thanks for the learnin’. Didn’t know the story of the HMS Venturer, that was a new one to me. ---
**Author:** ![whorfin](https://avatars.discourse-cdn.com/v4/letter/w/6f9a4e/32.png) [@whorfin](https://boards.straightdope.com/u/whorfin)\ **Post date:** [March 3, 2010, 6:22pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/10 "2010-03-03T18:22:28Z")
> [@t-bonham@scc.net](#): > > Also, in WWII, hunting other subs would be a _distraction_ from their primary mission, which was to starve out the other side by sinking their cargo ships. Spending time on anything other than that was contrary to orders, and to their basic purpose. Even sinking a battleship or carrier, while exciting to sub commanders, meant neglecting their basic mission. The real critical targets were oil tankers (at least in the Pacific). > > Note that submarines were ranked according to the _cargo tonnage_ that they had sunk. Thus USS Flasher is listed as the ‘top’ US submarine. This needs a little qualification: it wasn’t uniformly true that the “primary mission” of WWII submarines was anti-shipping. The relative priority of warship targets and shipping developed over the course of the war. To generalize a little: the German navy started off with a firm focus on attacking shipping, the U.S. Navy assigned a high priority to warship targets at the start of the Pacific War, but soon realized the value of targeting shipping (and later focused this to put a high priority on tankers), and the Japanese Navy began and continued to prioritize warship targets over shipping–to the extent that, by the middle of the Pacific war, there was almost no threat to shipping between the continental U.S. and Hawaii, and so there were almost no convoys in that area (as sharply contrasted to the Eastern Seaboard, where U-Boats were aggressive, and convoys predominated). In fact, one of the reasons that the Japanese Navy’s subs were relatively ineffective was that they were mainly sent out after warships, or to assist the surface fleet (for example, at Midway, where the IJN sub fleet was sent out as a “trap” for the U.S. fleet, and only succeeded in sinking an already-crippled Yorktown), rather than attacking shipping. Of course, it’s a little more fine-grained than that–since the “mission” of a submarine might vary from patrol to patrol—but that doesn’t really affect the overall picture. Here ([http://www.navy.mil/navydata/cno/n87/usw/issue\_12/rising.html](http://www.navy.mil/navydata/cno/n87/usw/issue_12/rising.html)) is a useful discussion of U.S. sub strategy, which points out that in the early pacific war, > [@](#): > > Unfortunately the other Pearl Harbor patrols for that same period saw only limited success, at least partially because of the high priority placed on hard-to-target enemy capital ships. ---
**Author:** ![whorfin](https://avatars.discourse-cdn.com/v4/letter/w/6f9a4e/32.png) [@whorfin](https://boards.straightdope.com/u/whorfin)\ **Post date:** [March 3, 2010, 6:33pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/11 "2010-03-03T18:33:05Z")
> [@YamatoTwinkie](#): > > Per [wikipedia](http://en.wikipedia.org/wiki/HMS_Venturer_(P68)) > > The duel between the HMS Venturer (P68) and U-864 on 9 February 1945 was the only time in the history of naval warfare that one submarine intentionally sank another while both were submerged. While it is true that it was relatively rare in WWII for one sub to sink another while both were submerged, quite a few submarines were attacked and sunk by enemy subs while traveling on the surface. (and remember, WWII subs spent most of their time on the surface). Examples to hand: > **[Type B submarine](https://en.wikipedia.org/wiki/Type_B3_submarine)** > > The Cruiser submarine Type-B (巡潜乙型潜水艦, Junsen Otsu-gata sensuikan) was a class of submarine in the Imperial Japanese Navy (IJN) which served during World War II. The Type-B submarines were similar to the Type-A apart from not having the headquarters installation. > The Type-B submarines were divided into four classes: > Project number S37. Twenty boats were built between 1937 and 1944 under the Maru 3 Programme (Boats 37 - 42) and Maru 4 Programme (Boats 139 - 152). > Project number S37B. Six boat... I-28, I-29 > **[Type D submarine](https://en.wikipedia.org/wiki/Type_D_submarine)** > > The I-361 class submarine (伊三百六十一型潜水艦, I-san-byaku-roku-jū-ichi-gata Sensuikan), also called Type-D submarine (丁型/潜丁型潜水艦, Tei-gata/Sen-Tei-gata sensuikan) or Sen'yu/Sen'yu-Dai type submarine (潜輸型/潜輸大型潜水艦, Sen'yu-gata/Sen'yu-Ōgata sensuikan) was a type of the 1st class submarine in the Imperial Japanese Navy serving during the Second World War. The type name, was shortened to Yusō Sensuikan Ō-gata (輸送潜水艦大型, Transport Submarine-Large Type). > The I-373 class submarine (伊三百七十三型潜水艦, I-san-byaku-nana... I-364, I-365, I-371 and I-373 > **[USS Corvina](https://en.wikipedia.org/wiki/USS_Corvina_%28SS-226%29)** > > USS Corvina (SS-226), a Gato-class submarine, was the only ship of the United States Navy to be named for the corvina. > Corvina's keel was laid down by the Electric Boat Company of Groton, Connecticut, on 21 September 1942. She was launched on 9 May 1943, sponsored by Mrs. LaRene P. Christie, wife of Rear Admiral Ralph. W. Christie, commander of submarine operations in Fremantle, Australia, and commissioned on 6 August 1943. > Clearing New London, Connecticut, on 18 September 1943, Corvina arr... ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [March 3, 2010, 7:02pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/12 "2010-03-03T19:02:37Z")
Although the development of nuclear power plants and the associated endurance permitted longer patrols (necessary for naval superpowers like the United States and Britain), there are plenty of diesel-electric hunter killer (HK) boats that perform just as aptly at more limited duration regional patrol duty. The innovation that permitted submarines to become a serious threat to other (submerged) submarines wasn’t nuclear propulsion but the increase of capability in passive sonar which allowed subs to locate threatening subs and direct guided torpedoes to the target. The impetus for this development was, of course, to counter guided missile and (later) ballistic missile submarines deployed by the Soviet Union on deterrence patrols. For the US Navy, the _Barracuda_-class subs were the first dedicated anti-submarine boats with an advanced acoustics suite (the [BQR-4](http://www.cavalla.org/atops.html)), although their range and endurance made them of limited operational effectiveness. The _Tang_-class subs were the first class of submarines that really filled the roll of dedicated sub-killers (intended to counter the converted Soviet _Whiskey_-class guided missile subs and _Zulu_-class ballistic missile subs and later the _Golf_- and _Hotel_-class boomers). The wide patrol limitations of the _Tangs_ resulted in the use of nuclear powerplants in the _Skate_- and _Skipjack_-classes of HKs. With the end of the Cold War and the lack of need to defend against regular deterrence patrols (the Russian Navy boomers spent a goodly portion of their post-Soviet years tied up to piers for lack of operating funds) the USN has been trying to convert attack subs to more multi-mission roles, including all-up cannisterized Tomahawks for ground-attack missions and more surveillance/sigint applications. Stranger ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [March 5, 2010, 6:56am UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/13 "2010-03-05T06:56:44Z")
The change that made this happens was when the nuclear warhead equipped ICBM became deploy-able via submarine. Submarines then replaced aircraft carriers as the navy’s new capital ships (carriers having previously replaced battleships) because they then were now the most powerful weapon system on Earth. Which meant that they were now the biggest and most important military targets on Earth. So an entirely new class of vessel, the attack sub, warranted being created with the specific design and purpose of being capable of destroying these apocalyptically powerful new subs if necessary. ---
**Author:** ![flurb](https://avatars.discourse-cdn.com/v4/letter/f/51bf81/32.png) [@flurb](https://boards.straightdope.com/u/flurb)\ **Post date:** [March 5, 2010, 2:05pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/14 "2010-03-05T14:05:01Z")
As has been pointed out, having submarines hunting for submarines during World War II would have been a tremendous waste of resources. There’s a LOT of ocean out there, and sending out subs on seek-and-destroy-other-sub missions would have been a needle in a haystack proposition. Moreover, there was no need to do so – a submarine a thousand miles from the nearest ship isn’t a threat to anyone. It’s only when it’s in proximity to a ship that the threat materializes, and there were more efficient ways of dealing with that threat (e.g. the convoy system). It was only when ballistic missile submarines became threats from anywhere on the planet that it became worthwhile to develop the ability to locate and hunt them wherever they might be. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [March 5, 2010, 3:30pm UTC](https://boards.straightdope.com/t/when-did-submarines-become-a-major-threat-to-other-subs/531041/15 "2010-03-05T15:30:08Z")
Mention has to be made of the [USS Batfish](http://en.wikipedia.org/wiki/USS_Batfish_(SS-310)), which holds the record for most subs sunk by a sub (3). But they were all on the surface, so they don’t count towards the OP.