GAU-8

GAU-8 Avenger
The GAU-8/A Avenger's barrel and breech assembly (ammunition drum off right edge of photo).
Type	Gatling-type
Place of origin	United States
Service history
In service	1977–present
Used by	United States Air Force (Avenger) Various navies (Goalkeeper)
Production history
Manufacturer	General Electric
Number built	Approx. 715
Variants	GAU-12/U Equalizer GAU-13/A
Specifications
Weight	619.5 lb (281 kg)
Length	19 ft 10.5 in (6.06 m) (total system) 112.28 in (2.85 m) (gun only)
Barrel length	90.5 in (2.30 m)
Width	17.2 in (0.437 m) (barrels only)
Cartridge	30×173 mm
Caliber	30 mm caliber
Barrels	7-barrel (progressive RH parabolic twist, 14 grooves)
Action	Electrically controlled, Hydraulic-Driven
Rate of fire	4,200 rpm (variable)
Muzzle velocity	3,324 ft/s (1,010 m/s) (API)
Effective firing range	4,000 feet (1,220 m)
Maximum firing range	Over 12,000 feet (3,660 m)
Feed system	Linkless feed system

The General Electric GAU-8/A Avenger is a 30 mm hydraulically driven seven-barrel Gatling-type that is typically mounted in the United States Air Force's Fairchild Republic A-10 Thunderbolt II. Designed specifically for the anti-tank role, the Avenger delivers very powerful rounds at a high rate of fire. The GAU-8/A is also used in the Goalkeeper CIWS ship weapon system, which provides defense against short-range threats such as highly maneuverable missiles, aircraft, and fast maneuvering surface vessels.

The GAU-8 was created as a parallel program with the A-X (or Attack Experimental) competition that produced the A-10. The specification for the cannon was laid out in 1970, with General Electric and Philco-Ford offering competing designs. Both of the A-X prototypes, the YA-10 and the Northrop YA-9, were designed to incorporate the weapon, although it was not available during the initial competition; the M61 Vulcan was used as a temporary replacement. Once completed, the entire GAU-8 assembly (correctly referred to as the A/A 49E-6 Gun System) represents about 16% of the A-10 aircraft's unladen weight. Because the gun plays a significant role in maintaining the A-10's balance and center of gravity, a jack must be installed beneath the tail of the plane whenever the gun is removed for inspection in order to prevent the aircraft from tipping rearwards.

The gun is placed slightly off center in the nose of the plane with the front landing gear positioned to the right of the center line, so that the actively firing cannon barrel is directly on the aircraft's center line. The gun is loaded using Syn-Tech's linked tube carrier GFU-8/E 30 mm Ammunition Loading Assembly cart. This vehicle is unique to the A-10 and the GAU-8.

The A-10 and its GAU-8/A gun entered service in 1977. It was produced by General Electric, though General Dynamics Armament and Technical Products has been responsible for production and support since 1997 when the division was sold by Lockheed Martin to General Dynamics.