Origins conceived of the aerial torpedo The idea of dropping lightweight torpedoes from aircraft was conceived in the early 1910s by
Bradley A. Fiske, an officer in the
United States Navy. A patent for this was awarded in 1912. Fiske worked out the mechanics of carrying and releasing the aerial torpedo from a
bomber, and defined tactics that included a night-time approach so that the target ship would be less able to defend itself. Fiske imagined the notional
torpedo bomber would descend rapidly in a sharp spiral to evade enemy guns, then at an altitude of about would level off long enough to line up with the torpedo's intended path. The aircraft would release the torpedo at a distance of from the target. if there was enough water (depth and expanse) for the torpedo to run. However, the
United States Congress appropriated no funds for aerial torpedo research until 1917 when the U.S. entered into direct action in
World War I. The U.S. would not have special-purpose torpedo planes until 1921.
First torpedo aircraft Meanwhile, the
Royal Naval Air Service (RNAS) began actively experimenting with this possibility. The first successful aerial torpedo drop was unofficially performed by the later
RFC pilot Charles Gordon Bell on 27 July 1914 – dropping a
Whitehead torpedo from a
Short S.64
seaplane. Gordon Bell was followed the next day by RNAS pilot
Arthur Longmore, when officially testing an aerial torpedo. The success of these experiments led to the construction of the first purpose-built operational torpedo aircraft, the
Short Type 184, built from 1915. An order for ten aircraft was placed, and 936 aircraft were built by ten different British aircraft companies during the
First World War. The two prototype aircraft were embarked upon
HMS Ben-my-Chree, which sailed for the
Aegean on 21 March 1915 to take part in the
Gallipoli campaign. Around the same time of the Royal Navy experiments, in Italy Captain
Alessandro Guidoni of the was conducting similar trials since 1913, with the help of inventor
Raúl Pateras Pescara, and in February 1914 successfully dropped an 800 lb torpedo, leading to disputes over which country first used an aerial torpedo.
First World War was the first torpedo aircraft when built in 1915 launching an aerial torpedo In November 1914, Germans were reportedly experimenting at
Lake Constance with the tactic of dropping torpedoes from a
Zeppelin. In December 1914, Squadron Commander
Cecil L'Estrange Malone commented following his participation in the
Cuxhaven Raid that "One can well imagine what might have been done had our
seaplanes, or those which were sent out to attack us, carried torpedoes or light guns." On 12 August 1915 a
Short Type 184, piloted by
Flight Commander Charles Edmonds, was the first aircraft in the world to attack an enemy ship with an air-launched torpedo. Operating from in the
Aegean Sea, Edmonds took off with a , torpedo to fly over land A limitation to using the Short more widely as a torpedo bomber was that it could only take off carrying a torpedo in conditions of perfect flying weather and calm seas, and, with that load, could only fly for a little more than 45 minutes before running out of fuel. In 1931, the Japanese Navy developed the
Type 91 torpedo, intended for a
torpedo bomber to drop from a height of and a speed of . As well, the Japanese Navy developed night attack and massed day attack doctrine, and coordinated aerial torpedo attacks between land- and carrier-based torpedo bombers. The Mark 13 differed from aerial torpedoes used by other nations in that it was wider and shorter. German aerial torpedo development lagged behind other belligerents—a continuation of neglect of the category during the 1930s. At the beginning of World War II, Germany was making only five aerial torpedoes per month, and half were failing in air-drop exercises. Instead, Italian aerial torpedoes made by
Fiume were purchased, with 1,000 eventually delivered. torpedo bomber takes off from the
aircraft carrier Zuikaku during the
Battle of the Coral Sea. In August 1941, Japanese aviators were practicing dropping torpedoes in the shallow waters of
Kagoshima Bay, testing improvements in the Type 91 torpedo and developing tactics for the attack of ships in harbor. They discovered that the
Nakajima B5N torpedo bomber could fly , somewhat faster than expected, without the torpedoes striking the bottom of the bay down. On December 7, 1941, the leading wave—40 B5Ns—used the tactic to score more than 15 hits during the
attack on Pearl Harbor. In April 1942,
Adolf Hitler made the production of aerial torpedoes a German priority, and the
Luftwaffe took the task over from the
Kriegsmarine. The
Mark 13 torpedo was the main American aerial torpedo, yet it was not perfected until after 1943 when tests showed that it failed in 70 percent of the drops made from aircraft traveling faster than . The
Helmover torpedo, a five-ton guided weapon launched from a heavy bomber, was developed by the British
Ministry of Aircraft Production for use against enemy shipping, but its introduction in 1945 meant that it was not used in action.
Korean War After World War II, anti-aircraft defenses were sufficiently improved to render aerial torpedo attacks suicidal. Lightweight aerial torpedoes were disposed or adapted to small attack boat usage. The only significant employment of aerial torpedoes was in
anti-submarine warfare.
Modern weapons of
VP-16 deploying a
Mark 46 torpedo, 2013 Since the advent of practical
anti-ship missile technology, pioneered in World War II with the
MCLOS-guided
Fritz X as early as 1943, aerial torpedoes have largely been reduced to use in anti-submarine warfare. Missiles are generally much faster, with longer range, and without the same launch altitude limitation of aerial torpedoes. Some modern aerial anti-submarine torpedoes do have the necessary
guidance capability to engage surface vessels, though given the widespread availability of missiles on aircraft and the small, specialized warhead on anti-submarine aerial torpedoes, this is not an option normally considered. At the peak of the
Falklands War, the
Argentine Air Force, in collaboration with the
Navy, outfitted an
FMA IA 58 Pucará prototype, AX-04, with pylons to mount Mark 13 torpedoes. The aim was the possible production of Pucaras as torpedo-carrying aircraft to enhance the anti-ship capabilities of the Argentine air forces. Several trials were performed off
Puerto Madryn, but the war was over before the technicians could evaluate the feasibility of the project. As a result of the loss of the role of anti-shipping aerial torpedoes in modern
naval doctrine, true
torpedo bomber units no longer exist in modern armed forces. The most common platform for aerial torpedoes today is the ship-borne anti-submarine helicopter, followed by fixed-wing anti-submarine aircraft such as the American
P-3 Orion. '' helicopter carrying a
MK46 torpedo. The
caveat to the above are torpedoes delivered by missiles/rocket systems, designed for anti-submarine warfare. Some designs are a straightforward mating of a rocket-propulsion system to the torpedo with a purely
ballistic attack profile, such as the American
ASROC. More complex, aerial drone-based system with
autopilot have also been deployed, such as the Australian
Ikara. Most such systems are designed to deploy from surface ships, though exceptions exist such as the
Soviet navy RPK-2 Viyuga, which can be launched from both surface ships and submarines. Given the relatively
soft nature of submarines, modern anti-submarine aerial torpedoes are much smaller than anti-ship aerial torpedoes of the past, and often classified as light weight torpedoes. They are also often of cross-platform design, able to deploy from both aircraft and surface ships. Examples include the American
Mark 46,
Mark 50 and
Mark 54 torpedoes. There are few if any aerial torpedo designs that are also used by submarines, owing to the significantly reduced capability of aerial torpedoes compared with their full-sized submarine counterparts such as the American
Mark 48 torpedo. == Design ==