A Revolver cannon is a type of autocannon commonly used as an aircraft gun. It uses a cylinder with multiple chambers, like those of a revolver handgun, however unlike a hand revolver the system employs a loading and case disposal mechanism with its rotation, to speed up the loading-firing-ejection cycle. Some examples are also power-driven, to further speed the loading process, but this is by no means universal. A revolver cannon differs from a Gatling gun in having only a single barrel, so the spun weight is lower and lends itself to gas operation. Automatic revolver cannons have been produced by many different European manufacturers, whereas the U.S., and to a lesser extent Russia, generally favor the Gatling gun.
The principal advantage of a revolver cannon tends to be weight reduction, compared to Gatling guns the cannon has but one barrel thus only the weight of one barrel. Another possible advantage depending on caliber is volume reduction the revolver cannon may take up less space, in the tight volume constraints of an airframe. Its smaller size reduces the need for additional mounting hardware. Revolver cannons tend to enjoy decent accuracy.
The principal disadvantage of revolver cannons is the inevitable wear and tear. With only one barrel the weapon must sustain the rate of fire and heating loads. This results in the weapon having generally a lower rate of fire, 3-4 times lower than their Gatling rivals. Because of this firing, many revolver cannons have short barrel lives. Some large ones last no more than 1,500 rounds before requiring a new barrel.