The AA Mine Discharger was a Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese anti-aircraft weapon of the Second World War. The device was a simple tube like an infantry mortar of 70 mm or 81 mm caliber

Caliber

In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....

. Instead of a standard mortar bomb, the projectile was a tube containing seven individual mines, each approximately 11/16ths of an inch in diameter (18 mm) and 3 inches (76.2 mm) long. Each mine was equipped with its own parachute

Parachute

A parachute is a device used to slow the motion of an object through an atmosphere by creating drag, or in the case of ram-air parachutes, aerodynamic lift. Parachutes are usually made out of light, strong cloth, originally silk, now most commonly nylon...

. When fired, the mortar threw the shell to a range of 3,000 to 4,000 feet (900 to 1,200 m) and a maximum altitude of approximately 600 m. The shell ejected the mines at the top of its arc. They would then float down on their parachutes. They were fused to detonate on contact or after a fixed time period, damaging nearby aircraft.

The weapon could also be used like a simple cluster bomb

Cluster bomb

A cluster munition is a form of air-dropped or ground-launched explosive weapon that releases or ejects smaller sub-munitions. Commonly, this is a cluster bomb that ejects explosive bomblets that are designed to kill enemy personnel and destroy vehicles...

, by firing over enemy troops.

External links

• http://www3.plala.or.jp/takihome/aa.htm
• http://www.lonesentry.com/articles/jp_ormoc/
• http://www.ibiblio.org/hyperwar/Japan/IJA/HB/HB-9-2.html

See also

• Unrotated Projectile
  Unrotated Projectile
  The Unrotated Projectile, or UP, was a short range rocket-firing anti-aircraft weapon developed for the Royal Navy to supplement the 2 pounder Pom-Pom gun due to a critical lack of close-range anti-aircraft weapons. It was used extensively by British ships during the early days of World War II...
  
  a British rocket launched parachute aerial mine system for ship defence.