Mousetrap (weapon)

Mousetrap (ASW Marks 20 and 22) was an anti-submarine rocket used mainly during the Second World War by the U.S. Navy. Its development was begun in 1941 as a replacement for Hedgehog, a British-made projector, which was the first ahead-throwing ASW weapon. These, however, were spigot-launched, placing considerable strain on the launching vessel's deck, whereas Mousetrap was rocket-propelled. As a result, Mousetrap's four or 8 rails for 7.2inch (183mm) rockets saved weight and were easier to install. The rockets weighed 30kg (65pd) each, with a 15kg (33pd) Torpex warhead and contact pistol, exactly like Hedgehog. By the end of the war, over 100 Mousetrap Mark 22s were mounted in U.S. Navy ships, including 3 each on 13 destroyers. One of these, USS Turner, was blown up by a faulty Mousetrap.

Statistics

• Round weight: 65lb (30kg)
• Warhead: 33lb (15kg)
• Range: about 280m
• Firing speed: one round every 3 seconds (maximum)
• No. of rails:
  1. Mark 20: 4
  2. Mark 22: 8

Sources

Fitzsimons, Bernard, ed. "Mousetrap", in Encyclopedia of Twentieth Century Weapons and Warfare, Volume 18, pp1946-7. London: Phoebus Publishing, 1978.

• http://www.navweaps.com/Weapons/WAMUS_ASW.htm
• http://www.navweaps.com/Weapons/WAMRussian_ASW.htm
• http://www.microworks.net/pacific/armament/mk20&22_mousetrap.htm