Mauser and Aden Cannon
The Mauser BK-27 is a 27mm cannon fitted to the Tornado GR4 aircraft for air-to-air or air-to-ground firing. The cannon is a single-barrel, high performance, breech-cylinder gun operated by a fully automatic electrically fired gas-operated system at a selective rate of 1000 or 1700 rounds per minute.
The belted-link ammunition box is positioned to the side of the gun-feed mechanism and a floating buffer system imposes a very small recoil and vibration load on the airframe of the aircraft. Spent cartridge cases and empty links are ducted from the rear of the gun into a collection bay immediately behind the gun. Automatic ram air purges the gun compartment and spent cases bay during and after firing.
The weapon has a very good hit-accuracy and one of its main strengths is the cannon’s ability to achieve a full 1700-rounds-per-minute rate of fire almost from the first round. This is an important asset, particularly if the cannon is being used against a fast-moving target. Targeting of the cannon is done through the aircraft’s head-up-display (HUD). When the cannon is selected in the cockpit, a firing predictor is projected onto the HUD; this depicts a moving line (continuously compacted impact line), or snake, that predicts where the next few rounds of cannon fire will go.
The cannon has a very high muzzle velocity and its high rate of fire, coupled with its ability to fire several different types of high-explosive shells, make it equally suitable for both interceptor- type aircraft and ground-attack aircraft alike. The system is relatively compact, extremely robust and its simple, rugged design makes it highly reliable.
The Aden cannon is a fully automatic, single-barrelled, five-chambered rotating cylinder gun, which is fitted to the Hawk T1A. It is electrically fired and gas operated with a rate of fire of between 1200 and 1400 rounds per minute.
The single Aden cannon operated by the Hawk T1A is housed in an external gun-pod assembly bolted to the underside of the fuselage on the centre-line of the aircraft. The pod contains the cannon and a close-packed ammunition drum containing 100 rounds; it is possible to load a further 30 rounds into the system by using the feed chute. During firing the empty cartridges are ejected overboard and the links retained in a compartment at the rear of the pod. The cannon can be harmonised with the aircraft’s HUD to give a firing imagery display, which the pilot aligns onto the target.
The cannon is able to fire ball ammunition or high-explosive-tipped rounds and is used by the Hawk for air-to-air and air-to-ground training. The cannon has proved to be a very reliable weapon for many years in both its operational and training roles.