Bell UH-1 Iroquois

The Bell UH-1 Iroquois is a utility helicopter manufactured by Bell helicopter, commonly called the "Huey". It first flew in 1956 and since then over 16,000 have been produced, making it the most produced western helicopter.

History

Earlier helicopters such as the Sikorsky R-4 and the Bell 47 had used piston engines. By the early 1950s turbine engines were being used in fixed wing aircraft and a turbine engine that could turn it's trust into shaft power had been developed, called the turboshaft engine. A major advantage to using a turboshaft engine in a helicopter is that they have a higher power to weight ratio, provide more power for the equivalent size and require less maintenance. the first bell helicopter to use a turboshaft engine was a modified version if the Bell 47, designated the XH-13F and first flown in October 1954. The in 1955 with United States Army needed a MEDEVAC helicopter to replace the Bell H-13 Sioux that had been used in the Korean war, and as a result the United States Army awarded Bell a contract to develop a turboshaft powered MEDEVAC helicopter, designated the XH-40. The first prototype of the XH-40 was flown by Floyd Carlson at Fort Worth on 22 October 1956. Two more prototypes were made the year after, and 18 YH-40 test aircraft were made in 1958. The Bell UH-1 soon entered service under the designation HU-1A, which is where it gets it's nickname, the "Huey".

Variants

UH-1A

The UH-1A was the first variant of the UH-1 and had a company designation of Model 204. The UH-1A has a 44-foot diameter rotor and is powered by a Lycoming T53-L-1A turboshaft which put out 860 SHP. The Army requested 183 UH-1As and deliveries began in June 30, 1959 and were completed in 1961. The UH-1A was used for MEDEVAC in Alaska, Europe and Korea, and fifteen were deployed to Vietnam in September 1962. The fifteen that were deployed to Vietnam were fitted with an M60 machine gun on each side and a 2.75 inch 8 round rocket pod on each side making a total of 16 rockets.

UH-1B

The UH-1B was an improved version of the UH-1A with a more powerful Lycoming T53-L-5 turboshaft engine which developed 960 SHP. The UH-1B started its user evaluation testing on 28 November 1960 and by June 1963 it had most light helicopter companies had transferred from the Piaseki CH-21 to the UH-1B, it also going on to eventually replace the less powerful UH-1A. It could carry a crew of 2 and 7 troops or 3 stretchers, or 2998 pounds of cargo. The UH-1B was also used as a gunship to protect the unarmed troop carriers, these gunships were fitted with four M60 machine guns and clusters of eight 2.75 inch rockets.