Among modern rotary‑winged aircraft, the Bell “Huey” series stands out. Though in no way extraordinary in design, they have been made in more quite different versions than any other rotary‑winged machines in history, and in much greater numbers.
The Bell Model 204 was designed in 1954 to meet a US Army specification for a military helicopter for casualty evacuation, troop carrying, and pilot training. Bell chose a turboshaft engine, which considerably increased the price but also improved the flight performance. Bell placed the engine behind the gearbox driving the 44‑ft main rotor with a semi‑rigid hub and two aluminum alloy blades with extruded spars, with a stabilizer bar mounted at right angles to the blades right on top of the hub. This tough and efficient rotor, which did not have to fold, was a significant factor in the trouble free development of the XH‑40. One of its characteristics was “rotor slap” which has ever since made it possible to hear one of these helicopters several minutes before it comes into view.
Bell Aircraft won the contract with its Model 204; it was the first turbine‑powered aircraft adopted by the Army.. The Army ordered three prototypes, designated XH‑40. The first of these flew at Fort Worth on October 22, 1956, piloted by Floyd Carlson, less than 16 months after the project had begun.
The prototypes were followed by six YH‑40 pre‑production aircraft, delivered in August 1958 for evaluation. The YH‑40 was different in some respects, notably in that the cabin was 30 cm (1 ft) longer and could accommodate two crew and eight troops or four stretchers.. Other modifications included 10 cm (4 in) higher landing skids, a wider access door and changes to the controls.
After a series of intensive trials in various climatic conditions, the US Army decided to order a further batch of nine, which were known as HU‑1 (Helicopter Utility) under the Army Air Forces' new, independent system of aircraft designation. The first HU‑1 left the factory in September 1958 and was delivered to an experimental base in Alaska for cold weather trials. In October 1959, it was sent to Fort Rucker for tests with Nord SS11 missiles.
As the Iroquois, the HU‑1A was the first version to be ordered in large numbers, in March 1959. By this time it had been redesignated HU‑1 (Helicopter, Utility 1), which resulted in the enduring name of “Huey”. To confuse matters, the designation was soon changed yet again, to UH‑1A. Delivery of the first batch of 100 was not completed until June 1961; from spring 1960, the Iroquois was also assigned to light aviation units overseas (in Korea and Europe). Fourteen were fitted with IFR avionics and were assigned to the Army Aviation School. Various weapons fits were then tested on the HU‑1A, including six Nord AGM‑22A wire‑guided missiles, four Emerson M73 7.62 mm machine guns or a General Electric automatic grenade launcher, as well as 70 mm rockets. The armed HU‑1As went into action in Vietnam in October 1962 equipped with two 7.62 mm guns and 16 air‑to‑ground rockets.
The Hueys played a major role in the war in Vietnam carrying troops, flying armed patrol and casualty evacuation. Bell upgraded the aircraft over three decades and expanded its production worldwide. Over 15,000 UH‑1 helicopters were ultimately produced, and many remain on active duty to this day.
The aircraft displayed here, (TH‑IL) is one of 45 produced for the U.S. Navy for training and rescue duties.