Mark 37 torpedo
Encyclopedia
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
with electrical propulsion, developed for the US Navy after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. It entered service with the US Navy in the early 1950s, with over 3,300 produced. It was phased out of service with the US Navy during the 1970s, and the stockpiles were sold to foreign navies.
Its engineering development began in 1946 by Westinghouse
Westinghouse Electric (1886)
Westinghouse Electric was an American manufacturing company. It was founded in 1886 as Westinghouse Electric Company and later renamed Westinghouse Electric Corporation by George Westinghouse. The company purchased CBS in 1995 and became CBS Corporation in 1997...
-ORL. It was based on the active homing system tested on modified Mark 18
Mark 18 torpedo
The Mark 18 torpedo was an electric torpedo used by the US Navy during World War II.The Mark 18 was built in competition to the Bureau of Ordnance electric torpedoes, which had been in development at the Newport Torpedo Station , Newport, Rhode Island, since the 1920s, in particular the Mark II,...
s, with added passive homing and a new torpedo body. Between 1955-56, thirty torpedoes were produced for development testing, with large-scale production commenced shortly afterwards. http://www.webcitation.org/query?url=http://www.geocities.com/Pentagon/1592/ustorp5.htm&date=2009-10-25+09:26:07
Due to its electric propulsion, the torpedo swam smoothly out of the launch tube, instead of having to be ejected by pressurized air, therefore significantly reducing its acoustic launch signature.
The guidance of a Mk37 mod 0 torpedo was done by a gyroscope
Gyroscope
A gyroscope is a device for measuring or maintaining orientation, based on the principles of angular momentum. In essence, a mechanical gyroscope is a spinning wheel or disk whose axle is free to take any orientation...
control during the initial part of its trajectory, where the gyro control achieved a straight run, a passive sonar
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
homing system, and at the last 700 yards by a Doppler
Doppler effect
The Doppler effect , named after Austrian physicist Christian Doppler who proposed it in 1842 in Prague, is the change in frequency of a wave for an observer moving relative to the source of the wave. It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from...
-enabled active sonar homing, with magnetostrictive
Magnetostriction
Magnetostriction is a property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization. The variation of material's magnetization due to the applied magnetic field changes the magnetostrictive strain until reaching its saturation value, λ...
transducer
Transducer
A transducer is a device that converts one type of energy to another. Energy types include electrical, mechanical, electromagnetic , chemical, acoustic or thermal energy. While the term transducer commonly implies the use of a sensor/detector, any device which converts energy can be considered a...
s operating at 60 kHz. The electronics was based on miniature vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s, later on solid-state semiconductor devices.
The mod.1 torpedoes were longer, slower and heavier than mod.0, but offered better target acquisition
Target Acquisition
In the military, target acquisition denotes any process that provides detailed information about enemy forces and locates them with sufficient accuracy to permit continued monitoring or attacking it....
capabilities and higher ability to intercept agile submarine
Submarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s. They used wire-guidance.
The efficiency of Mk37 torpedoes was high for targets with speed lower than 20 knots and depth less than 1000 ft (304.8 m). As submarines with higher speeds and operating depths appeared, new torpedoes were developed. Of them, NT37C, D, E, and F are based on the Mk37 design.
In 1967, the mod 0s started being refurbished as mod 3, and mod 1 as mod 2. These modifications involved many changes including replacement of magneto-constrictive transducers with piezoelectric ones, and resulted in target acquisition range increased from 700 yd (640.1 m) to 1000 yd (914.4 m) without loss of sensitivity with increasing depth.
The torpedoes used Mark 46 silver-zinc batteries. These had a known tendency to overheat, occasionally causing fires or explosions. Training torpedoes used reusable rechargeable secondary batteries.
For a long time, the Mark 37 was a primary U.S. submarine
Submarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
-launched ASW
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....
torpedo. It was replaced by the Mark 48
Mark 48 torpedo
The Mark 48 and its improved ADCAP variant are heavyweight submarine-launched torpedoes. They were designed to sink fast, deep-diving nuclear-powered submarines and high-performance surface ships.-History:...
starting in 1972. The remaining inventory was then rebuilt and sold to several countries, including Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...
, as the NT-37C after the vacuum tube guidance systems were replaced by solid-state electronics and the electric propulsion was replaced with a liquid monopropellant.
Note: the Mk 67 Submarine Launched Mobile Mine
Naval mine
A naval mine is a self-contained explosive device placed in water to destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, an enemy vessel...
http://www.fas.org/man/dod-101/sys/ship/weaps/mk-67.htm is based on a Mark 37 torpedo body. It entered service in 1983 and is capable of swimming as far as 10 miles through or into a channel, harbor, shallow water area and other zones which would normally be inaccessible to the vessel laying it. After reaching the target area it sinks to the sea bed and acts like a conventionally laid "influence mine". The exploder in the Mk 67 warhead is computerised and incorporates magnetic, acoustic and pressure sensors.
General characteristics
- Power plant: Mark 46 silver-zinc battery, two-speed electric motor
- Length: 135 inches (342.9 cm) (mod.0), 161 inches (408.9 cm) (mod.1)
- Weight: 1430 pounds (648.6 kg) (mod.0), 1660 pounds (753 kg) (mod.1)
- Diameter: 19 inches (48.3 cm)
- Range: 23000 yards at 17 knots, 10000 yards at 26 knots
- Depth: 1000 feet (304.8 m)
- Speed: 17 knots, 26 knots
- Guidance system: active/passive sonar homing; passive until about 700 yards from target, then active; mod.1 with wire-guidance
- Warhead: 330 pounds (149.7 kg) HBXHBXHBX is a family of binary explosives that are composed of RDX, TNT, powdered aluminium, and D-2 wax with calcium chloride. It is used in missile warheads and underwater ordnance....
-3 high explosive with contact exploder - Date Deployed: 1957 through 1987