The GAU-19/B .50 caliber Gatling Gun is a lightweight gatling gun for application on a variety of air, land and sea platforms, including helicopters, fixed wing aircraft, land-based vehicles, naval vessels and high-speed patrol boats. With a rate of fire of 1,300 shots per minute, the .50 caliber GAU-19/B provides superior firepower in a lightweight system. The total system weight of the three barrel GAU-19/B is neutral to that of a single barrel machine gun. The GAU-19/B has an unmatched 40,000 mean rounds between failure with the first scheduled maintenance begining at 35,000 rounds. It fires a standard NATO .50 caliber M9-linked ammunition. The gun’s automatic clearing cycle ensures live rounds are not left in the gun.
The GAU-19/A (GECAL 50) was first manufactured by General Electric, then by Lockheed Martin, and now by General Dynamics. Design work began in 1982. Early prototypes had six barrels, but a three-barreled configuration is now standard. The GAU-19/A was originally designed as a larger, more potent version of the M134 Minigun. Due to the loss of nine helicopters in Grenada, GE started building prototypes of the weapon in both a three-barreled and a six-barreled configuration. The six-barreled version was designed to fire 4,000 rounds per minute, and could be adapted to fire up to 8,000 rounds per minute. The GAU-19 takes 0.4 seconds to reach maximum firing rate. Soon it was recommended as a potential armament for the V-22 Osprey.The magazine would be located underneath the cabin floor and could be reloaded in-flight. However, plans to mount the gun were later dropped. In December 1992 the US Navy issued a letter of qualification for GAU-19/A integration and use on naval aircraft.
In October 2010 General Dynamics began developing the lighter weight GAU-19/B in response to an urgent needs statement issued by the Armed Scout Helicopter Program Office. By April 2011 flight testing had begun and by January 2012, the U.S. Army ordered 30 GAU-19/B versions for use on helicopters. All were delivered by the next month. In August 2012 the GAU-19/B received a safety confirmation from the US Army Evaluation Center for use on the OH-58D Kiowa Warrior. Both GAU-19 variants have been integrated on naval vessels (tripod and remote weapons station), vehicles (turret and remotely operated), and on both rotary and fixed wing aircraft (externally mounted under wing fixed forward and man fired from the aircraft door or cargo ramp. Most recently a self-contained gun pod was developed by Fulcrum Concepts LLC.