UH-1B

The Bell UH-1 Iroquois military helicopter, first introduced in 1959, is the first production member of the prolific Huey family of helicopters, and was itself developed in over twenty variants, which are listed below.

The first Bell helicopter to use a turbine engine was a modified Model 47 (designated XH-13F), which had its initial flight in October 1954. The U.S. Army began a competition for a new helicopter for general utility and medical/casualty evacuation in 1955. In June 1955, Bell Helicopter was awarded a contract to develop the next generation turbine-powered utility helicopter for the U.S. Army. The resulting Bell Model 204 was designated XH-40 by the U.S. military and first flew on 22 October 1956. Two more prototypes were built in 1957, and six YH-40 pre-production helicopters were delivered in 1958. The YH-40's cabin was lengthened by12 in (30 cm), and had more ground clearance compared to the XH-40.

Bell believed the YH-40 was ideal for troop transport and cargo carrying as well as the medevac role, a view soon adopted by the Army; they found the pre-production aircraft so much better in service than previous piston-powered helicopters they soon ordered more.

The HU-1A (later redesignated the UH-1A) was the first turbine-equipped U.S. helicopter to go into production, and production models first entered service with the 101st Airborne Division at Fort Campbell, Kentucky, the 82nd Airborne Division and the 57th Medical Detachment. Although they were intended for evaluation only, the Army quickly pressed them into operational service and Hueys with the 57th Medical Detachment arrived in Vietnam in March 1962.

The helicopter was originally designated the HU-1A, which is where it received its nickname - "Huey." The official U.S. Army designation Iroquois (Army helicopters are traditionally given Native American names) was almost never used in practice.

Fourteen of the original order of UH-1As were designated as TH-1A which were used for crew training and a single aircraft was redesignated XH-1A for grenade launcher testing in 1960.

The first UH-1As to arrive in Vietnam after the 57th Medical Detachment were with a new test unit, the US Army's Utility Tactical Transport Company (UTTCO). UTTCO had 20 "Alpha" Hueys and deployed to Vietnam in the fall of 1962. These aircraft were used as armed escorts to the existing H-21 Shawnees and H-34 Choctaws troop carriers.

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