Gatling gun
While missiles have been the primary armament since the early 1960s, the Vietnam War showed that guns still had a role to play and most fighters built since then are fitted with cannons (typically between 20 and 30 mm in caliber) as an adjunct to missiles. Modern European fighter aircraft are usually equipped with the revolver cannon, whereas the United States and to some extent Russia generally favor the Gatling gun. The Gatling gun quickly became the weapon of choice for most air forces.