Although the A-10 can carry a considerable weight of disposable stores, its primary built-in weapon is the 30 mm GAU-8/A Avenger Gatling gun. One of the most powerful aircraft cannon ever flown, it fires large, depleted uranium armor-piercing shells at a rate of about 3,900 rounds per minute (50 rounds per second during the first second followed by 70 rounds per second). The massive shells and high muzzle velocity allow the Avenger to destroy heavily armored main battle tanks in as little as 6 direct hits. The gun is accurate as well, capable of placing 80% of its shots within a 30-foot wide circle from a distance of 1 mile while the aircraft is in flight. The fuselage of the plane is actually built around the gun (for instance, the nosewheel is offset to starboard so that each barrel of the gun can be aligned on the centreline when it fires.) The A-10 carries 1,350 rounds of 30 mm ammunition and the damage caused by a proportion of those rounds prematurely firing from impact of an explosive shell would be catastrophic. It is for this reason that a great deal of effort has been taken to protect the 5 ft (1.52 m) wide, 9 ft (2.74 m) long drum. There are many plates of varying thicknesses between the skin and the drum; these plates are called trigger plates because when an explosive shell hits a target it first penetrates its armour then detonates, as the drum has many layers of thin armour the shell's detonation is triggered before reaching the drum. Then a final layer of armour around the drum itself protects it from fragmentation damage.
Despite the power of the GAU-8, the principal weapon of the A-10 is the AGM-65 Maverick air-to-surface missile, with electro-optical targeting. The Maverick allows targets to be engaged at much greater ranges than the cannon, a safer proposition in the face of modern anti-aircraft systems. During Desert Storm, in the absence of NVG, the Maverick's camera was used for night missions. Other weapons include cluster bombs and rocket pods. It is also capable of carrying hellfire missiles. Although the A-10 is equipped to deliver conventional and laser-guided bombs, their use is relatively uncommon. A-10s usually fly with an ECM pod under one wing and two AIM-9 Sidewinder air-to-air missiles under the other for self-defense.