A US Air Force HH-60G Pave Hawk helicopter arrived in the rain at Edwards Air Force Base (AFB) in California, USA, on Jan 5, 2016, to begin testing the ballistic dispersion of a GAU-21 .50 caliber machine gun as a replacement for its existing weapons.
The Pave Hawk will be at Edwards until January 22 where the 412th Test Wing and 418th Flight Test Squadron are providing the facilities, range safety, photographic documentation and maintenance support equipment. The test team aims to accomplish baseline ballistics testing at Edwards AFB’s Gun Harmonizing Range.
The testing program is part of the Air Combat Command’s HH-60 Defensive Weapons System Upgrade modification proposal. This requires the new weapon to be an open bolt system, have a longer barrel life and higher cyclic rate of fire, be lighter weight and have reduced recoil, and it must also be currently used by other Department of Defense services.
The current weapon used on the HH-60 is a closed-bolt GAU-18 which has a short barrel life (3,000 rounds), a relatively low cyclic rate of fire (550 rounds/minute), a high recoil and has a vulnerability to unsafe ammunition ‘cook-offs’.
The FN Herstal M3M, designated the GAU-21, is an open bolt system with a barrel life of 10,000 rounds, a cyclic rate of fire of up to 1100 rounds/minute, and reduced recoil over standard .50 caliber weapons due to the use of a soft mount.
The current test effort is focused on integrating the GAU-21 into the HH-60G weapon platform using the Gun Mount/Ammunition Handling System, which was designed for the Air Force by the US Navy.
The objective of this test effort is to evaluate the ballistic dispersion of the GAU-21 .50 caliber machine gun when mounted to the HH-60G in the fixed forward fire and fixed side fire modes.
The Pave Hawk, a variant of the UH-60 Blackhawk used by the Army, is primarily used for combat search and rescue and differs from a Blackhawk in its auxiliary fuel tanks, aerial refueling probe and forward-looking infrared. It also has a color weather radar, integrated electronic warfare suite, external gun mount and ammunition handling system as well as an integrated navigation suite.
January 15, 2016