The Bliss–Leavitt Mark 8 torpedo was the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

's first by

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...

. Although introduced prior to

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

, most of its combat use was by

PT boats A PT boat (short for patrol torpedo boat) was a motor torpedo boat used by the United States Navy in World War II. It was small, fast, and inexpensive to build, and it was valued for its maneuverability and speed. However, PT boats were hamper ...

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. The torpedo was originally designed in 1911 by Frank McDowell Leavitt of the

E. W. Bliss Company The E. W. Bliss Company was a manufacturer of machine tools founded by Eliphalet Williams Bliss. The company was based in Brooklyn, New York and relocated to Hastings, Michigan in 1919. History In 1857, Bliss formed a partnership with John Mays. ...

and entered full mass production in 1913 at the

Naval Torpedo Station The Naval Undersea Warfare Center (NUWC) is the United States Navy's full-spectrum research, development, test and evaluation, engineering and fleet support center for submarines, autonomous underwater systems, and offensive and defensive weapons ...

Newport, Rhode Island Newport is a seaside city on Aquidneck Island in Rhode Island, United States. It is located in Narragansett Bay, approximately southeast of Providence, Rhode Island, Providence, south of Fall River, Massachusetts, south of Boston, and nort ...

. It was deployed on

destroyer In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy, or carrier battle group and defend them against a wide range of general threats. They were conceived i ...

s and

battleships A battleship is a large, heavily naval armour, armored warship with a main battery consisting of large naval gun, guns, designed to serve as a capital ship. From their advent in the late 1880s, battleships were among the largest and most form ...

during

and

cruiser A cruiser is a type of warship. Modern cruisers are generally the largest ships in a fleet after aircraft carriers and amphibious assault ships, and can usually perform several operational roles from search-and-destroy to ocean escort to sea ...

s built in the 1920s. All US battleships and most cruisers had their torpedo tubes removed by 1941. The Mark 8 remained in service through World War II on older destroyers, primarily the ''Wickes'' and ''Clemson'' classes. It also equipped

PT boat A PT boat (short for patrol torpedo boat) was a motor torpedo boat used by the United States Navy in World War II. It was small, fast, and inexpensive to build, and it was valued for its maneuverability and speed. However, PT boats were hampe ...

s early in World War II, but was replaced by the

Mark 13 torpedo The Mark 13 torpedo was the U.S. Navy's most common aerial torpedo of World War II. It was the first American torpedo to be originally designed for launching from aircraft only. They were also used on PT boats. Design Originating in a 1925 ...

on most of these in mid-1943. Under the

Lend-Lease Act Lend-Lease, formally the Lend-Lease Act and introduced as An Act to Promote the Defense of the United States (),

, about 600 Mark 8 torpedoes were issued to the United Kingdom for use with 50 pre-1930 destroyers it received under the

Destroyers for Bases Agreement The destroyers-for-bases deal was an agreement between the United States and the United Kingdom on 2 September 1940, according to which 50 , , and -class US Navy destroyers were transferred to the Royal Navy from the US Navy in exchange for lan ...

Design

The design was originally intended to be used on

s in an anti-

surface ship Surface combatants (or surface ships or surface vessels) are a subset of naval warships which are designed for warfare on the surface of the water, with their own weapons and armed forces. They are generally ships built to fight other ships, subma ...

role. When it was first released, it was a highly advanced torpedo, but when it was actually deployed into service during World War II it was showing its age and unable to compete with modern torpedo technology. The low speed of the torpedo was one of the complaints; its Japanese counterpart, the

Type 93 torpedo The was a -diameter torpedo of the Imperial Japanese Navy (IJN), launched from surface ships. It is commonly referred to as the Long Lance by most modern English-language naval historians, a nickname given to it after the war by Samuel Eliot ...

, was significantly faster and more difficult to spot in the water.

Deployment difficulties

The Mark 8 had many technical difficulties with its design that would be a bane to the torpedomen who would use them. The first issue came with the process of simply launching the torpedo, which was fraught with its own set of difficulties. The

gyro Gyro may refer to: Science and technology * GYRO, a computer program for tokamak plasma simulation * Gyro Motor Company, an American aircraft engine manufacturer * '' Gyrodactylus salaris'', a parasite in salmon * Gyroscope, an orientation-sta ...

in the torpedo was sensitive when it was first launched and it would need to be launched from an even

keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...

, otherwise the torpedo would lose stability when it hit the water. The other issue concerned the launching mechanism. The initial system was set with a

black powder Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, charcoal (which is mostly carbon), and potassium nitrate, potassium ni ...

charge to push the torpedo out of the tube. This was a problem in the

South Pacific The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

, where the humid climate would cause these charges to misfire, sometimes not putting enough force behind the torpedo to fully eject it from the tube. One other risk of these misfires was what is called "hot running", where the torpedo would run in its tube. Though the

warhead A warhead is the section of a device that contains the explosive agent or toxic (biological, chemical, or nuclear) material that is delivered by a missile, rocket (weapon), rocket, torpedo, or bomb. Classification Types of warheads include: *E ...

could not detonate, the motor would overheat and explode without water to cool it, sending splinters across the deck. Another issue was that the tubes were heavily lubricated with oil and grease to ensure that the torpedo was smoothly launched from the tube. Sometimes during launch, the charge would ignite the lubricants in the tube causing a fire emitting black smoke that would reveal the location of the torpedo boat. The torpedo lacked the explosive power of newer models. It carried less than of TNT-based explosives, which was far from a guaranteed ship kill. This frustrated many captains who, when hitting an enemy dead on, had the warhead detonate but not sink the target, and many targets escaped.

Design

Deployment difficulties

See also

References

Further reading