The Mark 14 torpedo was the United States Navy's standard submarine-launched anti-ship torpedo of World War II. This weapon was plagued with many problems which crippled its performance early in the war. It was supplemented by the Mark 18 electric torpedo in the last two years of the war. From December 1941 to November 1943 the Mark 14 and the destroyer-launched Mark 15 torpedo had numerous technical problems that took almost two years to fix. After the fixes, the Mark 14 played a major role in the devastating blow U.S. Navy submarines dealt to the Japanese naval and merchant marine forces during the Pacific War.
By the end of World War II, the Mark 14 torpedo was a reliable weapon ultimately remaining in service for almost 40 years in the U.S. Navy, and even longer with other navies.
Development
The design of the Mark 14 started in January 1931; the Navy allocated $143,000 for its development. The Mark 14 was to serve in the new "fleet" submarines and replace the Mark 10 which had been in service since World War I and was standard in the older R- and S-boats. Although the same diameter, the Mark 14 was longer, at , and therefore incompatible with older submarines' torpedo tubes. Later in the war, the Bureau of Ordnance (BuOrd) stopped producing Mark 10s for the S-boats and provided a shortened Mark 14.
Torpedoes consist of several subsystems, and those subsystems evolved over time. Torpedoes are also tailored for their application. Submarine torpedoes, such as the Mark 14, are constrained by the dimensions of the submarine's torpedo tubes: 21 inches in diameter and a certain maximum length. Submarines are expected to close with their targets, so the torpedoes do not need a long range. In contrast, torpedoes fired by destroyers need greater range because their approach would be under fire from their targets. Improvements in the propulsion engine power output allowed the Mark 14 to have a top speed of compared to the Mark 10 Mod 0's . Steering is controlled by a gyroscope; the gyro on the Mark 10 Mod 0 was spun up in the torpedo tube and was not powered after launch; the gyro on the Mark 14 was continuously powered by its air flask. The depth control on the Mark 10 was slow — the depth would not stabilize quickly; the Mark 14 depth stabilization was improved.
The design for the Mark 6 exploder used in the Mark 14 torpedo had started at the Naval Torpedo Station (NTS), Newport, in 1922. Ship armor was improving with innovations such as torpedo belts and torpedo blisters (bulges). To circumvent these measures, torpedoes needed larger warheads or new technology. One option would use a fairly small warhead argues small explosive is enough but was intended to explode beneath the keel where there was no armor. This technology required the sophisticated new Mark 6 magnetic influence exploder, which was similar to the British DuplexFitzsimons, Bernard, general editor. The Illustrated Encyclopedia of 20th Century Weapons and Warfare (London: Phoebus Publishing, 1978), Volume 8, p. 807, "Duplex" and GermanDönitz, Memoir. models, all inspired by German magnetic mines of World War I. The Mark 14 shared this exploder with the concurrently-designed surface ship Mark 15 torpedo.
The Mark 6 exploder, designated Project G53, was developed "behind the tightest veil of secrecy the Navy had ever created." Exploders were tested at the Newport lab and in a small field test aboard . At Ralph Christie's urging, equatorial tests were later conducted with , which fired one hundred trial shots between 10°N and 10°S and collected 7000 readings. The tests were done using torpedoes with instrumented exercise heads: an electric eye would take an upward-looking picture from the torpedo; the magnetic influence feature would set off some gun cotton. Inexplicably, no live fire trials were ever done with production units. Chief of Naval Operations William V. Pratt offered the hulk of Fitzsimons, Volume 5, p. 541, table. destroyer , but prohibited the use of a live warhead, and insisted the BuOrd pay the cost of refloating her if she was sunk in error. These were strange restrictions, as Ericsson was due to be scrapped.Between 1934 and 1936. Fitzsimons, Volume 5, p. 542, "Cassin". BuOrd declined. A service manual for the exploder "was written—but, for security reasons, not printed—and locked in a safe."
Torpedoes were sophisticated and expensive. The cost of a torpedo in 1931 was about $10,000 ().; stating that $803,000 was allocated for the production of 76 torpedoes. The development of the Mark 13, Mark 14 and Mark 15 torpedoes was done frugally. The Navy did not want to do live fire tests that would destroy a $10,000 torpedo. The Navy was also reluctant to supply target ships. Consequently, there were no live-fire tests, and the designers had to rely on their judgment. This sometimes led to problems: a contact exploder that worked reliably at failed at . In addition, the Navy had limited experience in using torpedoes in combat.
Supply and production
The U.S. Navy has a long history of torpedo supply problems. In 1907, the Navy knew there was a problem with torpedo supply; a major contractor, the E. W. Bliss Company, could produce only 250 torpedoes per year. During World War I, the Navy had almost 300 destroyers that each had 12 torpedo tubes. The Bliss Company was to produce about 1,000 torpedoes for the Navy, but that production was delayed by demands for artillery shells and only 20 torpedoes were close to being shipped before WWI started for the U.S. When war was declared on Germany, another 2,000 torpedoes were ordered. To produce large numbers of torpedoes, the government loaned $2 million to Bliss Company so it could build a new factory. Although the government had ordered 5,901 torpedoes, only 401 had been delivered by July 1918. The supply problems prompted the Navy to build the U.S. Naval Torpedo Station, Alexandria, VA, but WWI ended before the plant was built. The plant produced torpedoes for five years, but was shuttered in 1923.
In 1923, Congress made NTS Newport the sole designer, developer, builder and tester of torpedoes in the United States. No independent or competing group was assigned to verify the results of Mark 14 tests.
The Navy had not learned from the torpedo supply lessons of WWI. Looking back in 1953, the Bureau of Ordnance stated, "Production planning in the prewar years was also faulty. Torpedoes were designed for meticulous, small-scale manufacture. When military requirements demanded that they be supplied in large numbers, a series of new problems was exposed. There were simply no realistic plans available for providing the weapon in adequate quantity." There was little interest in torpedo production until 1933 when the Vinson Shipbuilding Program recognized the need for torpedoes to fill the torpedo tubes on its newly constructed ships. Consequently, Newport received new production equipment and an increased budget. NTS produced only 1½ torpedoes a day in 1937, despite having three shifts of three thousand workers working around the clock. Production facilities were at capacity and there was no room for expansion.
By January 1938, unfilled torpedo orders at Newport amounted to $29,000,000. A forecast that did not include war estimated Newport would have a backlog of 2425 torpedoes by 1 July 1942. More production was needed. The simplest route was to reopen the Alexandria Torpedo Station, but New England congressmen objected to reopening Alexandria; they wanted production concentrated in New England. The Navy side-stepped the opposition by including the Alexandria funds as part of the Naval Gun Factory's 1939 budget. The Naval Torpedo Station at Keyport, Washington, was also expanded.
"Although torpedo production was still low—3 a day—when the national emergency was proclaimed in September 1939, an investment of almost $7,000,000 assured early improvement." By the fall of 1941, Alexandria had been reopened. The required production rate for torpedoes was raised to 50 per day. Both Newport and Alexandria went to 3 shifts operating 7 days per week, but their combined torpedo production was 23 torpedoes per day. The Navy contracted with the American Can Company to produce torpedoes.
The short supply of Mark 14 torpedoes was compounded by a 10 December 1941 Japanese air raid on Cavite Navy Yard in the Philippines. The attack destroyed 233 Mark 14 torpedoes.
After the U.S. entered the war, the contract with American Can was expanded and Pontiac Motor Company, International Harvester, E. W. Bliss Company, and Precision Manufacturing Co. were retained as contractors. In May 1942, Westinghouse Electric Corporation was asked to build an electric torpedo (which became the Mark 18 torpedo).
Only 2,000 submarine torpedoes were built by all three Navy factories (Newport, Alexandria, and Keyport) during 1942. This exacerbated torpedo shortages; the Pacific Fleet Submarine Force had fired 1,442 torpedoes since war began. In the words of BuOrd's own account of WWII, "Until the spring of 1945, supply was a problem" for the Mark 14 torpedo.
The torpedo shortage at the start of the war also meant that commanders did not want to waste torpedoes on testing.
Controversy
The Mark 14 was central to the torpedo scandal of the U.S. Pacific Fleet Submarine Force during World War II. Inadequate production planning led to severe shortages of the weapon. The frugal, Depression-era, peacetime testing of both the torpedo and its exploder was woefully inadequate and had not uncovered many serious design problems. Torpedoes were so expensive that the Navy was unwilling to perform tests that would destroy a torpedo. Furthermore, the design defects tended to mask each other. stating, "what was worse, however, was the diabolical way in which each defect concealed another." Much of the blame commonly attached to the Mark 14 correctly belongs to the Mark 6 exploder. These defects, in the course of fully twenty months of war, were exposed, as torpedo after torpedo either missed by running directly under the target, prematurely exploded, or struck targets with textbook right angle hits (sometimes with an audible clang) yet failed to explode.
Responsibility lies with the Bureau of Ordnance, which specified an unrealistically rigid magnetic exploder sensitivity setting and oversaw the feeble testing program. Its small budget did not permit live fire tests against real targets. Instead, any torpedo that ran under the target was presumed to be a hit due to the magnetic influence exploder, which was never actually tested. Therefore, additional responsibility must also be assigned to the United States Congress, which cut critical funding to the Navy during the interwar years, and to NTS, which inadequately performed the very few tests made. The Bureau of Ordnance failed to assign a second naval facility for testing, and failed to give Newport adequate direction.
Problems The Mark 14 torpedo had four major flaws. It tended to run about deeper than set. The magnetic exploder often caused premature detonation. The contact exploder often failed to detonate the warhead. It tended to run "circular", failing to straighten its run once set on its prescribed gyro-angle setting, and instead, to run in a large circle, thus returning to strike the firing ship. claims there were 24 cases of circular running torpedoes, but avoids the topic because "it is not clear that any particular defect caused any or all of these circular runs." was sunk by a Mark 18 (not a Mark 14); may have been sunk by a Mark 18. had a circular run because the gyro was not installed.