The revolver cannon BK 27 was developed against the stringent requirements for Nato air forces for the use in aircraft. Today, more than 3,000 BK 27 are in service all over the world, in aircraft such as the Tornado, the Alpha Jet and the Gripen. The performance assessment of aircraft cannons for the Eurofighter in the 1980s resulted in no alternative to the BK 27.
The main features of the BK 27mm are high performance, high kill probability and reliability using a broad variety of ammunition.
For the Eurofighter, the BK 27 installation introduced, for the first time for a revolver gun, a linkless-closed ammunition feed system, the Linkless Ammunition Box (LAB). Apart from eliminating the risks associated with the ejection of cases and links, such a self-contained feeding system results in a significant volume reduction of about 60%. Thus, a risk free and modular adapted weapon system is available for integration into future fighter aircraft.
In the Eurofighter Typhoon the BK 27 is installed with a linkless ammunition box.
FAPDS AMMUNITION - FRANGIBLE ARMOUR PIERCING
The Frangible Armour Piercing (FAP) round can be deployed in both the air-to-ground and air-to-air roles.
The "Frangible" concept was developed to defeat both "hard" and "soft" targets, without recourse to the use of conventional high explosives and fuses. Based on the well-proven Oerlikon Contraves sub-calibre technology, employing an in-situ plastic-moulded tungsten alloy core with integrated driving band, the FAPDS ammunition has a very high muzzle velocity. As a result, a flat projectile trajectory and a short flight time significantly increase the hit probability. The FAP rounds were especifically designed for aircraft cannon such as the M 39 and M 61.