The Oerlikon KCA is a Swiss gas-operated single-barrel revolver cannon developed for aircraft use. Its most noticeable use was on the Saab 37 Viggen fighter mounted on a conformal pod. The KCA fires a shell that is 50% heavier than the NATO standard ammunition used on ADEN and DEFA cannon. It can fire up to 1350 rounds per minute at a muzzle velocity of , with an effective range of