UH-1 "Huey" utility helicopter series
In 1955, Bell started the development of the prototype of the XH-40 utility helicopter to meet army specifications. The army's first turbine powered aircraft first took off on 20th October, 1956. It was named Huey and was developped and tested more.
The Bell HU-1 could carry seven personnels or three stretchers apart from the pilot. The HU-1 Iroquois was the first model that was ordered in large numbers. Since 1959, 13 models have been evolved, from A through V. It was widely used in Vietnam from 1962.
Hueys armed with two door guns were called "Slicks" because of their uncluttered external appearance. They were the backbone of airmobile combat operations in Vietnam. Unarmed MedEvac Hueys were called "Dust Offs", because of the clouds of dust kicked-up at landing. The Huey replaced the CH-21 Shawnee in the combat assault role. It has two-bladed, semi-rigid metal main rotor and tail rotor. HU-1 was redesignated later that was teh UH-1.
The choppers were continuously developped. Some types, that were good in the States or elsewhere, wasn't suitable for Vietnam's battlefields. Thus, some types were specially developped for the terrains of Vietnam.