General Electric’s 30-millimeter GAU-8 Avenger cannon has been the primary weapon of the U.S. Air Force’s A-10 Thunderbolt II ground-attack plane for more than 40 years. It also arms the Goalkeeper naval close-in weapon system. It’s a huge and awesome gun.
The GAU-8 has seven independent barrels with rotary-locking bolts that are mechanically actuated. The weapon is powered by a pair of hydraulic motors and can, in theory, spew up to 4,200 tank-smashing, depleted-uranium rounds per minute.
The threat of a massive Soviet armored push into Western Europe necessitated an aircraft and weapon system that could engage and destroy main battle tanks and armored personnel carriers.