ADEN cannon

ADEN cannon
A quad 30 mm ADEN cannon pack removed from a Hawker Hunter
Type	Revolver cannon
Place of origin	United Kingdom
Service history
Used by	See users
Production history
Designer	Armament Development Establishment
Designed	1946
Manufacturer	Royal Small Arms Factory
Produced	1953–present
Specifications
Weight	Overall: 87.1 kg (192 lb 0 oz) Barrel: 12.25 kg (27 lb 0 oz)
Length	Overall: 1.64 m (5 ft 5 in)
Barrel length	1.08 m (3 ft 7 in)
Shell	30×113mm
Caliber	30 mm (1.1811 inch) caliber
Barrels	Single barrel (progressive RH parabolic twist, 16 grooves)
Action	Gas operation featuring a pneumatic cocking system and a 26 volt DC electrical firing system
Rate of fire	1,200–1,700 rpm
Muzzle velocity	790 m/s (2,600 ft/s)

The Royal Small Arms Factory ADEN is a 30 mm revolver cannon used on many military aircraft, particularly those of the British Royal Air Force and Fleet Air Arm. Developed post-WWII primarily to meet British Air Ministry's requirement for increased lethality in aircraft armament, the cannon was fired electrically and is fully automatic once it is loaded.

The ADEN (named for the Armament Development Establishment, where it was designed, and Enfield, where it was produced) was developed in the late 1940s as a replacement for the older Hispano-Suiza HS.404 20 mm cannon used in British aircraft of World War II. It is based (as are the French DEFA cannon and American M39 cannon) on the mechanism of the German Mauser MG 213C, an experimental revolver cannon designed for the Luftwaffe, but never used in combat. The ADEN entered service on the Hawker Hunter in 1954, and subsequently used on every British gun-armed aircraft until the advent of the Panavia Tornado in the 1980s.

The current version is the ADEN Mk 4. Although its muzzle velocity of 2,592 ft/s (790 m/s) is lower than the Hispano's 2,789 ft/s (850 m/s), the substantially larger and heavier projectile makes the ADEN more lethal, and it has a higher rate of fire of about 1,300 rounds per minute.

An improved version, the ADEN Mk 5, incorporates a multitude of small changes to improve reliability and increase rate of fire slightly to 1,500–1,700 rounds per minute. No new Mk 5s were built, but many older weapons were converted, being redesignated Mk 5 Straden.