Make your own free website on

30 mm lightweight cannon and pod.

Continuing on from their family of 20 mm self-contained
cannon pods and the success of the 30 mm GAU-8/A
cannon, General Electric (now Martin Marietta Armament
Systems) decided to develop a lightweight 30 mm pod
type armament system for general use on fighter/ground
attack aircraft.

The overall armament system is self-contained and
requires only a trigger signal from the aircraft. It
consists of a GPU-5/A pod, the GAU-13/A cannon, a
helical closed loop ammunition feed system and a
self-contained pneumatic drive system with
microprocessor controls.
  The GPU-5/A pod is of all metal construction,
cylindrical in shape with a pointed cone shaped nose
and a rounded aft end. The primary structural component
of the pod is the strong hard back which is used to
mount the pod to the aircraft with the recoil adaptors
mounted inside it and connected by linkage to the
cannon. The pod skin is made of aircraft type aluminium
honeycomb, and the entire pod is designed to withstand
supersonic flight speeds. The hardback support can be
configured for use on a standard 762 mm rack or as an
adaptor for direct mounting on specific aircraft. The
GPU-5/A pod is 4.3 m long, has a body diameter of 610
mm, and when fully loaded weighs 841 kg.
  The GAU-13/A is 2.79 m long, has a maximum diameter
of 305 mm, and weighs 151 kg. It is a 30 mm
four-barrelled Gatling type cannon similar in design to
the GAU-8/A and employing the same reverse clearing
operation of the latter. However, whereas the GAU-8/A
is hydraulically operated the GAU-13/A is pneumatically
driven and has a lower firing rate of 2400 rds/min. All
barrels are rigidly clamped together and attached to
the forward end of the breech rotor which rotates in a
stationary housing. Each of the cannon's barrels fires
only once during each revolution of the barrel cluster,
and are attached to the cannon rotor by quick release
interrupted lugs. The cannon can reach its maximum
firing rate of 2400 rds/min in 0.4 s and has an average
recoil force of 2400 kg. The
cannon is estimated to have a Minimum Rounds Before
Stoppage (MRBS)
figure of 32,000.

GAU-13/A Cannon
Calibre: 30 mm
No of barrels: 4
Length: 2.79 m
Weight: 151 kg
Rate of fire: 2400 rds/min
Muzzle velocity: 1030 or 1036 m/s depending on
GPU-5/A Pod
Length: 4.3 m
Diameter: 610 mm
No of guns: 1 x 4 barrelled 30 mm
Ammunition capacity: 353 rds
Lug spacing: 762 mm
  (loaded) 841 kg
  (empty) 599 kg