Type 89 machine gun

Caliber: 7.7 mm (0.303 in)
Ammunition: 7.7 x 58SR (10.5 g)
Weight: 12 kg (26 lb)
Length: 1,140 mm (45 in)
Rate of fire: 900 rounds/min
Muzzle velocity: 810 m/s (2,660 ft/s)

From Wikipedia, the free encyclopedia

Type 89 refers to two families of unrelated Imperial Japanese Army aircraft machine guns. The first family is the recoil-operated Vickers gun. The Type 89 FIXED gun was a license-built Vickers E class gun chambered for the Type 89 cartridge (see below). It was used in synchronized applications in fighter cowls and in wing gun applications. It was belt-fed, using a steel link disintegrating belt.

The Type 89 FLEXIBLE gun was a gas-operated twin gun. That is, it was made up of two mirror-image Year 11 Type LMG actions lying on their sides supported by a tubing cradle. The guns were fed from quadrant magazines loaded with cartridges on five-round clips.

The Type 89 (special) was the Type 89 flexible with the magazines modified to use a captive belt made up of five-round clipd joined edge-to-edge. This is the version used in the Pacific War, having replaced the Type 89 flexible in 1937.

The Type 89 (modified single) is the flexible gun most often (erroneously) called "Type 89." It is a single Year 11 Type action laid on its side and fed from a flat pan magazine. It also was used throughout the Pacific War in applications where the (special) was too bulky to fit.

The flexible guns were used as backseat guns and bomber defense and were pressed into ground and AA use, though their small caliber made them ineffective in all roles during much of the Pacific War.

When any reference is made to a 7.7 Type 89, it is impossible to tell which gun is indicated without more information.