The longer tail boom incorporated a wider chord vertical fin on the tail rotor pylon and larger synchronized elevators.īell also introduced a dual hydraulic control system for redundancy as well as an improved inlet filter system for the dusty conditions found in southeast Asia. The increased power and a larger diameter rotor required Bell’s engineers to design a new tail boom for the UH-1C. The improved rotor resulted in better maneuverability and a slight speed increase. A new rotor system was developed for the UH-1C to allow higher air speeds and reduce the incidence of retreating blade stall during diving engagements. The Army would eventually refit all UH-1B aircraft with the same engine. Bell fitted the UH-1C with a 1,100 shp (820 kW) T53-L-11 engine to provide the power needed to lift all weapons systems in use or under development. Army testing of the UH-1B started in November 1960, with the first production aircraft delivered in March 1961.īell commenced development of the UH-1C in 1960 in order to correct aerodynamic deficiencies of the armed UH-1B. In response, Bell proposed the UH-1B, equipped with the Lycoming T53-L-5 engine producing 960 shp (720 kW) and a longer cabin that could accommodate either seven passengers or four stretchers and a medical attendant. The Army indicated the need for improved follow-on models even as the first UH-1As were being delivered. While glowing in praise for the helicopter’s advances over piston-engined helicopters, the Army reports from the service tests of the YH-40 found it to be underpowered with the production T53-L-1A powerplant producing a maximum continuous 770 shaft horsepower (570 kilowatts). After September 1962, the designation for all models was changed to UH-1 under a unified Department of Defense (DOD) designation system, but the nickname remained. Army name was almost never used in practice. The reference became so popular that Bell began casting the name on the helicopter’s anti-torque pedals. The helicopter quickly developed a nickname derived from its designation of HU-1, which came to be pronounced as “Huey”. In March 1960, the Army awarded Bell a production contract for 100 aircraft, which was designated as the HU-1A and officially named Iroquois after the Native American nations. Two more prototypes were built in 1957, and the Army had previously ordered six YH-40 service test aircraft, even before the first prototype had flown. Powered by a prototype Lycoming YT53-L-1 (LTC1B-1) engine producing 700 shp (520 kW), the XH-40 first flew on 20 October 1956 at Fort Worth, Texas, with Bell’s chief test pilot, Floyd Carlson, at the controls. On 23 February 1955, the Army announced its decision, selecting Bell to build three copies of the Model 204 for evaluation with the designation XH-40. Twenty companies submitted designs in their bid for the contract, including Bell Helicopter with the Model 204 and Kaman Aircraft with a turbine-powered version of the H-43. In November 1953, revised military requirements were submitted to the Department of the Army. The Army determined that current helicopters were too large, underpowered, or too complex to maintain easily. Army identified a requirement for a new helicopter to serve as medical evacuation (MEDEVAC), instrument trainer, and general utility aircraft. The Bell 204 and 205 are Iroquois versions developed for the civil market. The UH-1 first saw service in combat operations during the Vietnam War, with around 7,000 helicopters deployed. The Iroquois was originally designated HU-1, hence the Huey nickname, which has remained in common use, despite the official redesignation to UH-1 in 1962. The UH-1 was the first turbine-powered helicopter to enter production in 1960 for the United States military, and more than 16,000 have been built since. The first member of the prolific Huey family, it was developed by Bell Helicopter to meet a United States Army’s 1952 requirement for a medical evacuation and utility helicopter, and first flew in 1956. The Bell UH-1 Iroquois (nicknamed “Huey”) is a utility military helicopter powered by a single turboshaft engine, with two-blade main and tail rotors.