How effective were deck guns on submarines during World War 2? I know that the Germans in the Atlantic when attacking the convoys and the Americans in the Pacific going after Japanese shipping, to the extent that they designed and introduced a new gun, used them a fair bit but how important were they in the scheme of things compared to torpedoes? The British seem to of used them much less frequently so I was half wondering if they might not of been a good candidate to one of the first to drop deck guns, since IIRC their doctrine had submarines attacking warships rather than merchantmen.
Submarine Deck Guns?
- Thread starter Simon
- Start date
It depended on the circumstances and the doctrine of the submarine service in question. Torpedoes were considerably less reliable in those days, though that issue was steadily resolved, and deck guns could be used when hitting ships in a convoy to save a limited supply of torpedoes even when they were reliable.
In the Pacific side of the war, U.S. submarine commanders would often use their deck guns to sail into waters too shallow for a torpedo attack and strike Japanese cargo ships hiding along the Chinese coastline.
I would imagine the absolute last to get rid of deck guns on submarines would have been the U.S. Navy and the Kriegsmarine, as both services did extensive convoy raiding operations, and deck guns were very useful for that kind of thing with the technology of the era.
In the Pacific side of the war, U.S. submarine commanders would often use their deck guns to sail into waters too shallow for a torpedo attack and strike Japanese cargo ships hiding along the Chinese coastline.
I would imagine the absolute last to get rid of deck guns on submarines would have been the U.S. Navy and the Kriegsmarine, as both services did extensive convoy raiding operations, and deck guns were very useful for that kind of thing with the technology of the era.
Tyr Anazasi
Banned
It depends mostly on the circumstances. In the first years a sinking with the deck gun was possible for Uboats. In later years it did happen very seldomly. The last case I know is from 1944. Later the Germans relied only on the torpedoes and deleted the guns mostly. For the US it is another thing, as the Japanese lacked anti submarine ships and planes. So they kept the guns very longer.
Indeed. The fact that the Japanese for some reason didn't organize large convoys helped us a lot as well. Coming to the surface for a deck gun shootout is a lot less dangerous against a handful of ships than against a horde.
Ancientone
Banned
Deck guns were the preferred weapon of attack by U-boats in WW1, but the early use of convoys limited their use in WW2. They were used extensively against stragglers and against the unescorted single vessels off of the US coast during the "second happy time" in early 1942. But as surfacing in daytime near a convoy became problematic the use declined and the deck guns were removed from U-boats before the end of the war.
RN boats, AIUI, used them often enough, & had a doctrine placing more emphasis on them than, say, USN. USN emphasized torpedoes (then built one of the worst in the world,Simon said:
in inadequate numbers).Guns proved pretty useful against junks & sampans & barges, & small merchantmen, in PTO. AFAIK, guns alone were never used against an escort. They also served a useful purpose in delivering coups de grace.
USN ended up with pretty dismal 3"/50cal deck guns, as a result...
IMO, a 4"/50cal, like the Brits used, would have been ideal. Two, 1 each fore & aft, with port & starboard TBTs, would have been best IMO. (This would need some adjustment of trim tankage & ammo stowage...)U-boats probably found them most useful. Don't forget, most of the Allied sinkings were singletons, not in convoy...
Deck guns started off useful, but became less so as the war went on. Mainly because advancements in ASW techniques meant that surface attacks were less and less viable. Improvements in torpedoes also meant that they were more effective, and thus submariners were encouraged to use them more. IIRC the German Type-XXI didn't feature a deck gun, both because it was a very effective underwater attacker and because surface attacks had been made extremely dangerous.
The submariners who had to use the early U.S. torpedo agree with you, rest assured.
It's one of the reasons so many U.S. submarine skippers made use of their deck guns early on.Against an unarmored merchant hull, a three-inch gun isn't so bad. It's when you begin fighting warships that you start having problems, and the submarine wasn't really supposed to do that on the surface in the USN, not unless they had no real choice. Doctrine clearly stated that, when attacked by surface vessels or aircraft, the primary defense was submergence and silence. The primary weapon was the torpedo, secondaries were guns and mines, and the submarine on the surface in a wartime patrol was in diving trim at all times.
Basically, if I were a submarine skipper, I'd use my torpedoes against warships and most merchants, and only use the deck gun to conserve my torpedo stocks, and then only against merchant targets unless I had no choice.
Mookie
Banned
The deck guns were great weapons, the problem is a need to surface to fire it, and inability to use it in storms. But when used it not only saves torpedoes but also proves as an effective anti-ship weapon. German droped it due to rubber coating to evade sonars and because surfacing wasnt safe after 1942-3
This brings back memories.............
Like my thread proposing a number of German submarines could come in and bombard New York city.
I do not doubt that such a plan was considered, possibly multiple times. The idea of how effective it could have been early on is...distressing.
This brings back memories.............
Like my thread proposing a number of German submarines could come in and bombard New York city.
Say, with some these?
Say, with some these?
Those big gun subs were such an terrible waste of money. At the end of the day the idea of the big gun, light armour combination had been comprehensively demolished at Jutland and making it submersible doesn't help. Against any target against which a big gun is useful no sub captain in his right mind would surface.
A sub is a lousy gun platform - close to the water, heavily affected by wave action, easily damaged into mission-kill (one hole in the pressure hull...) - hence the deck gun was only useful against merchies.
Also, firing the gun creates noise and light, leading to detection - bad juju for a submarine against anything except singleton merchantmen.
Also, firing the gun creates noise and light, leading to detection - bad juju for a submarine against anything except singleton merchantmen.
Mookie
Banned
The merchants are a target of Subs, they arent designed for battle operations.
And that huge gun would split the sub if fired
Cook
Banned
The deck guns on submarines were not an effective weapon, something that had been recognised from action in the First World War; they required the submarine to not only be surfaced, but to also have crew on deck, making an emergency dive impossible.
The guns were there only because International Maratime Law at the time required that submarines comply with what were known as the Cruiser Rules: merchant ships must be stopped and searched for military contraband and the civilian crews allowed the oportunity to abandon ship in lifeboats before the ship was sunk by the submarine with the deck gun. The rules had been written well before submarines had even been invented and did not recognise the extreme vulnerability of a surfaced submarine. Once the futility of complying with the Cruiser Rules was recognised, the deck guns disappeared.
RN boats, AIUI, used them often enough, & had a doctrine placing more emphasis on them than, say, USN. USN emphasized torpedoes (then built one of the worst in the world,
Guns proved pretty useful against junks & sampans & barges, & small merchantmen, in PTO. AFAIK, guns alone were never used against an escort. They also served a useful purpose in delivering coups de grace.
USN ended up with pretty dismal 3"/50cal deck guns, as a result...
U-boats probably found them most useful. Don't forget, most of the Allied sinkings were singletons, not in convoy...
What I've read says a lot of the mid/late war Gatos and Balos had the 5"/25 as a deck gun rather than the old 3"/50.
http://en.wikipedia.org/wiki/5"/25_caliber_gun_(United_States)
While I suspect that - for all the reasons given above - that deck guns were really only useful for the first few generations of subs, I have read that late in WW2, the US subs made good use of them against Japanese merchants. They were only aable to do this of course as the Japanese "anti-submarine" measures were such shite. Using the guns enabled them to extend their cruises; in fact, years ago ( so long ago that i have no idea where) I did read that one US sub actually chose to go into a surface gun engagement with a Japanese escort - and sank it!
Anyone here read Operation Drumbeat, by Michael Gannon? Not only does the book tell the story of the U-Boat offensive against the U.S. East Coast, but it focuses on U-123 (LCDR Reinhard Hardegen) and her two deployments to the East Coast. Hardegen sank three ships with his deck gun alone when he ran out of torpedoes. Two on the first patrol, one on the second. His total score for five patrols as skipper (U-147 and U-123): 17.
That'd be correct- as boats came in for major refits & overhaul, they would be retrofitted with heavier deck guns were often part of the equipment upgrades, as combat experience showed that the 3"/50 was inadequate to deal with unarmed merchant ships & targets not worth a torpedo, such as sampans, junks, fishing boats, & other coastal traffic that subs would often go after on the surface, circumstances permitting.
The very first deck guns on US subs were 3"/23 guns on a pop-up mount where the breech would be stowed in a watertight structure built into the superstructure, with the barrel pointing straight up when stowed; these were used on the WW1 L & O-classes.
Later US subs had more conventional gun mountings, with easier to use wet mounts that would allow more powerful guns to be fitted, starting with the R-class, which had a 3"/50 mounted in front of the conning tower, and the S-class which had a 4"/50 in the same position, as did the later Dolphin. Barracuda had a 5"/51, but that gun was seen as unsuitable due to the difficulties of manhandling the separate projectile & charge without proper hoists on the deck of a submarine, as were the 6"/53s used on Argonaut & Narwhal, chosen because of their designed role as submarine cruisers when submarines were supposed to follow the cruiser rules in the interwar era.
However, in the interests of saving weight under the treaty regime, as well as a belief among some admirals that fitting heavier guns to submarines would encourage their captains to get into gun battles with merchant ships & small warships, starting with Cachalot, US subs reverted to the 3"/50, over the objections of submarine officers, such as Charles Lockwood, who advocated for the development of a new lightweight 4" gun, but there was never enough money in the budget to come up with such a weapon. However, their lobbying did lead to the gun foundations of submarines from Porpoise onwards to be built strongly enough to take a 5" gun in anticipation of future developments.
Subs through the early Gatos continued to be built with the 3"/50, but by late 1942, combat experience showed that gun to be inadequate, so later ones were built with 4"/50s removed from S-boats retired from front-line service, as were many of the Balaos, while the surviving earlier fleet boats were rearmed with them as they came in for overhaul during 1943, though several of the Tambor class boats were fitted with the 5"/51s originally mounted on the Barracudas. When the supply of former S-boat guns ran short, the shortfall was made up by converting 4"/50 guns removed from old 4-pipers that were rearmed with DP 3" guns for wet-mount operation.
However, even the 4" was seen as too light for operations against light coastal traffic, so starting in August, 1944, a light 5" gun, a wet mount version of the 5"/25 gun used as a heavy AA gun in large interwar surface ships, became available for retrofit on the newer boats, as well as being fit to new construction. By late 1944, a couple boats were fitted with what became the ultimate gun armament, 5"/25s fore & aft, as well as 40 mm Bofors mounted on platforms at both ends of the fairwater, and that proved to be so successful in operations against coastal & small craft traffic, that starting in January, 1945, that armament was authorized to be fitted to any submarine upon the request of the captain.
To make that armament even more effective, starting in February, 1945, BuOrd developed a compact fire-control system at the request of Adm. Lockwood, which had a fire control computer & stable element located in the CPO quarters, with target & own-ship's data from the tracking solution would be manually input, and a gunnery solution would be generated, which would be transmitted to the guns by remote indicator. The first such installation was made & successfully tested in late July, 1945, and 6 additional subs were so fitted by the end of the war. One of the submarine force's major procurement goals in the immediate post-war era was to acquire enough equipment to be able to fit that gun armament & fire control system to all active & reserve submarines, but that was soon overtaken by post-war developments.
However, deck guns survived in USN service through the early 1950s, both on unmodernized boats, and even a few of the early fleet snorkel conversions, such as can be seen in the attached pic of Argonaut II, taken at Malta in July, 1953, while even into the early 1960s, some of the fleet snorkel conversions done for boats being transferred to allied countries had them.