Torpedo
A self-propelled underwater weapon that uses acoustic homing or wire guidance to seek and destroy submarines and surface ships with a warhead detonated on impact or by proximity fuse.
Torpedoes are the primary ship-killing and submarine-killing weapons of underwater warfare. Modern heavyweight torpedoes like the American Mk 48 ADCAP are sophisticated autonomous weapons that use a combination of wire guidance (in which the submarine sends steering commands through a thin wire paid out behind the torpedo), active sonar homing (where the torpedo pings and tracks the target's echo), and passive acoustic homing (where it listens for the target's noise).
The Mk 48 ADCAP, carried by all U.S. Navy submarines, is a 3,500-pound weapon that can reach speeds exceeding 55 knots and follow a target to depths greater than 2,500 feet. Its 650-pound warhead is designed to detonate beneath a ship's keel, creating a gas bubble that breaks the ship's back, a far more destructive mechanism than the hull-piercing hits of World War II torpedoes.
Lightweight torpedoes like the Mk 54 are carried by surface ships, helicopters, and maritime patrol aircraft for anti-submarine warfare. These smaller weapons are dropped or launched into the water near a sonar contact and autonomously search for and attack the target. The ongoing development of torpedo countermeasures, including acoustic decoys, anti-torpedo torpedoes, and hull-mounted countermeasure systems, drives continuous improvement in torpedo guidance and counter-countermeasure capabilities.
Related Terms
Depth Charge
An anti-submarine weapon consisting of a canister of explosives set to detonate at a predetermined depth, designed to damage or destroy submarines underwater.
Mine
An explosive device placed on or below the surface of land or water, designed to detonate when contacted or triggered by the presence of a vehicle, ship, or person.
Sonobuoy
A small expendable sensor dropped from aircraft into the water that listens for submarine sounds and transmits the acoustic data back to the aircraft via radio.
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