U.S. Helicopter Armament Subsystems

The United States military has developed a number of Helicopter Armament Subsystems since the early 1960s. These systems are used for offensive and defensive purposes and make use of a wide variety of weapon types including, but not limited to machine guns, grenade launchers, , and rockets. Various systems are still in use, though many have become obsolete.

The helicopter has added much to the exploitation of the modern battlefield, changing traditional war-fighting scenarios to the extent that entirely new strategies and tactics have been developed both to utilise and deny the capabilities of these aircraft. In the air, against land-based threats, and at sea, helicopters can be used in offensive, defensive and transportation capacities to react swiftly to the fluid tactical conditions modern combat imposes on the battlefield.

Although one of the first armies to experiment with helicopters, the United States Army was slow to fully explore the possibilities of armed helicopter gunships. Experiments between the Korean War and US involvement in South East Asia were small and fairly simple. Learning much from their experience of these conflicts, the US decided to look further into the idea of air mobile tactics, and subsequently armed helicopters, though an armed helicopter had been proposed and rejected in the early 1940s. By the time the UTTHCO (Utility Tactical Transport Helicopter Company) was deployed to Vietnam in 1962, the US had started experimenting more with the idea of arming helicopters both for defensive and offensive purposes. UTTHCO was an expeditionary unit, deployed to Vietnam to assist the South Vietnamese Army and to provide on the ground testing for new air mobile theory. Weapon systems used by UTTHCO were often crude and made from parts and weapons readily available in the field.

By 1965, the United States had deployed a truly Air Mobile unit, the 17th Cavalry, which began to use more standardized armament systems. Throughout US involvement in Vietnam the US Army, US Marine Corps, and US Air Force would develop and utilize a number of armament systems designed for a variety of helicopters, and would pave the way for more dedicated attack helicopters.

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