Torpedo

A modern torpedo is a self-propelled guided projectile that operates underwater and is designed to detonate on contact or in proximity to a target.

In naval usage, the term "torpedo" was first used in the American Civil War to refer to tethered naval mines (developed by Matthew F. Maury, a Confederate Admiral). Around 1897, Nikola Tesla patented a remote controlled boat and later demonstrate the feasibility of radio-guided torpedoes to the United States military. Radio remote controlled torpedoes remained uninvestigated until the Space Age. During the World War I, torpedoes came to mean self propelled projectiles fired from a ship or submarine. Later, torpedoes were given (homing) guidance systems.

Torpedoes are weapons that may be launched from submarines, surface ships, helicopters and fixed-wing aircraft, and from unmanned naval mines. They are also used as parts of other weapons; the Mark 46 torpedo used by the United States becomes the warhead section of the ASROC (Anti-Submarine ROCket) and the Captor mine uses a submerged sensor platform that releases a torpedo when a hostile contact is detected. The three major torpedoes in the US Navy inventory are the Mark 48 heavyweight torpedo, the Mark 46 lightweight and the Mark 50 advanced lightweight.