Mousetrap (anti-Submarine Projector, Marks 20 and 22) was an

anti-submarine rocket An anti-submarine rocket is an anti-submarine weapon type deployed on surface warships for the purpose of sinking or damaging submarines by small explosive charges. They are similar to anti-submarine mortar but a comparably more modern system. T ...

launcher used mainly during

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 ...

by 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 ...

and

Coast Guard A coast guard or coastguard is a Maritime Security Regimes, maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with cust ...

. Its development began in 1941 as a replacement for

Hedgehog A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are 17 species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introduction. The ...

anti-submarine mortar Anti-submarine mortars are artillery pieces deployed on ships for the purpose of sinking submarines by a direct hit with a small explosive charge. They are often larger versions of the Mortar (weapon), mortar used by infantry and fire a projecti ...

. Those were

spigot A tap (also spigot or faucet: see usage variations) is a valve controlling the release of a fluid. Nomenclature United Kingdom * Tap is used in the United Kingdom and most of the Commonwealth for any everyday type of valve, particularly t ...

-launched, which placed considerable strain on the launching vessel's deck, whereas Mousetrap was rocket-propelled. As a result, Mousetrap's four or eight rails for rockets saved weight and were easier to install. The rockets weighed each, with a

Torpex Torpex ("Torpedo explosive") is a secondary explosive, 50% more powerful than TNT by mass. Torpex comprises 42% RDX, 40% TNT and 18% powdered aluminium. It was used in the Second World War from late 1942, at which time some used the names Torp ...

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 ...

and

contact pistol A naval mine is a self-contained explosive weapon placed in water to damage or destroy surface ships or submarines. Similar to anti-personnel and other land mines, and unlike purpose launched naval depth charges, they are deposited and left ...

, exactly like Hedgehog. By the end of the war, over 100 Mark 22 Mousetraps were mounted in U.S. Navy ships, including three each on 12

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

submarine chaser A submarine chaser or subchaser is a type of small naval vessel that is specifically intended for anti-submarine warfare. They encompass designs that are now largely obsolete, but which played an important role in the wars of the first half of th ...

s (usually two sets of rails).

Statistics

* Round weight: * Warhead: * Range: about * Firing speed: one round every 3 seconds (maximum) * No. of rails: ** Mark 20: 4 ** Mark 22: 8

Citations

Bibliography

External links

ASW Weapons of the United States of America
at NavWeaps

at NavWeaps {{U.S. WW2 rockets Anti-submarine missiles of the United States Explosive weapons Military equipment introduced from 1940 to 1944 Naval weapons of the United States World War II naval weapons World War II weapons of the United States Anti-submarine rockets