M61 Vulcan

The M61 Vulcan is a hydraulically, electrically, or pneumatically driven, six-barrel, air-cooled, electrically fired Gatling-stylerotary cannon which fires 20 mm caliber rounds at an extremely high rate (typically 6,000 rounds per minute). The M61 and its derivatives have been the principal cannon armament of United States militaryfixed-wing aircraft since 1959.

Designed in 1946 by General Electric, the Vulcan entered service with the U.S. military in 1959. As of 2000, it was produced by General Dynamics. It is also manufactured under license in Japan by Sumitomo Heavy Industries for Japan's Self-Defense Force and by SNT Dynamics in South Korea.