The GAU-13/A is a four-barreled rotary cannon based on the mechanism of the larger GAU-8, sharing the same massive 30 mm ammunition.

The pod is 4.3 metres (14 feet 1 inch) long and can be mounted on any standard NATO 762 mm (30.0 in) suspension lugs.

In the mid-1980s the USAF considered a specialized variant of the F-16 for the close air support (CAS) mission, using the GPU-5, as a substitute to or adjunct for the A-10 Thunderbolt II.

It was briefly tried on some Air National Guard F-16 Fighting Falcons during the 1991 Gulf War, but was removed from service after barely a day of combat use because of its very poor accuracy.

In mid/late 1995, the U.S. Marine Corps conducted a trial of the GPU-5 on the LCAC-66, as a potential weapon to provide suppressive fire for landing forces.