As with the XM8, this system can also be mounted on the OH-58 Kiowa. HGS-55 Using a mount similar to that used on the XM8 and M27 series, the HGS-55 was developed by the McDonnell Douglas Helicopter Company (formerly Hughes Helicopters) to use the EX 34 Mod 0 7.62×51mm chain gun. The weapon is supplied with a 2,000-round magazine, and the weapon fires between 550 and 700 rounds per minute. This system was not adopted by the US military for use, and no export sales were known to have been made. OH-13 Sioux and OH-23 Raven XM1/XM1E1 In service between 1960 and 1972, the XM1 consisted of two .30-caliber M37C machine guns mounted on the landing skids of either the OH-13 or OH-23 helicopter. These weapons were fixed forward, but flexible in elevation, with their ammunition (500 rounds per gun) stored externally. The XM1E1 was the product engineering design. What would appear to have been a variant of the XM1 system was used by UTTHCO on their HU-1As (later UH-1A) for a short period. M2 The M2 system was a variation on the XM1, replacing the .30-caliber M37C machine guns with 7.62×51mm NATO M60C machine guns. The mounts were similar to the XM1, also providing flexible elevation, with 650 rounds per gun stored externally. AH-58D/OH-58D Kiowa Warrior Universal Weapons Pylon and Gun Pod The Universal Weapons Pylon is specific to the OH-58D Kiowa Warrior helicopter, and provides two support racks for various weapon systems. The racks, with stores mounted, may be folded 180 degrees upward for rapid loading into the C-130 transport aircraft, though the connecting umbilicals must be disconnected to prevent damage. There are at least ten authorized armament configurations, which involve a mix of a system specific gun pod mounting the M296 .50 caliber machine gun (left side only), the M260 7-shot 2.75in/70mm Lightweight Launcher (LWL), the M279 2-rail AGM-114 Hellfire launcher, or a 2-shot Air-to-Air Stinger (ATAS) launcher. The gun pod is fed from a semi-external magazine loaded with 500 rounds of linked ammunition. MH-65C Dolphin and MH-68A Stingray Airborne Use of Force (AUF) Package The US Coast Guard has deployed the MH-68A to its newly created Helicopter Interdiction Tactical Squadron (HITRON), and it is the only helicopter in USCG inventory specifically tasked with the Airborne Use of Force (AUF) mission. These helicopters feature a defensive armament system composed of a single M240G machine gun mounted at