DEFA 552A/553/554 30 mm AIRCRAFT CANNON

30 mm cannon.

Development work on the DEFA 30 mm aircraft cannon
programme was started in the late 1940s by the GIAT
(Groupement Industriel des Armements Terrestres) group
and was originally based on the Second World War,
German Mauser Gun. The DEFA 554 entered operational
service in 1984 with the Mirage 2000, with two
fuselage-mounted cannons. They are also fitted to the
Brazilian version of the Alpha Jet. For the earlier
weapons, two DEFA 552/552As are standard equipment on
all Mirage 3 and Mirage 5 aircraft. Other aircraft
types fitted include Etendard IVM, Fiat G-91, Jaguar,
Kfir and Super Etendard. DEFA 553s are fitted to Alpha
Jet, CASA 101, Jaguar, Macchi MB-339K, Mirage F1 and
Pucara aircraft. All the above cannons are also
suitable for mounting in the CC 420 pod.

The DEFA range of 30 mm aircraft cannon all follow the
same basic design. They are a single barrelled cannon
featuring a revolving drum, electric firing pin and are
gas operated. The revolver drum has five cartridge
chambers and operates as follows; when a chamber is
in-line with the barrel, the preceding chamber is in
the case ejection position, while two are in the
loading position and the fifth remains empty.  In twin
installations a unit is needed for each gun and an
additional control and junction box provided. Both
cannons are credited with a muzzle velocity of 840 m/s,
and the steel chrome barrel fitted on current 552A and
553 cannons has a life of 5000 rounds. The DEFA 554 has
the same basic features as the earlier models. However,
it is longer at 2.01 m and weighs 80 kg. It uses the
same ammunition as the 552A and 553 but has two rates
of fire achieved electronically. They are, 1800 rds/min
for the air-to-air role and 1100 rds/min for the
air-to-surface role.

Calibre: 30 mm
No of barrels: 1
Length: 1.66 m
Weight: 81 kg
Rate of fire: 1300 rds/min
Muzzle velocity: 840 m/s

Calibre: 30 mm
No of barrels: 1
Length: 2.01 m
Weight: 80 kg
Rate of fire: 1100 or 1800 rds/min
Muzzle velocity: 820 m/s