A Bell XH-40, a prototype of the UH-1 and Bell 204
Bell designed its Model 204 in response to a 1955 United States Army requirement for a utility helicopter. The 204 was a giant step forward in helicopter design, being one of the first to be powered by a turboshaft. The turboshaft engine radically improved the practicality of the helicopter due to its light weight and high power-to-weight ratio, lower fuel consumption, and lower maintenance and operating costs. The use of a turboshaft in the 204 allowed it to carry a useful payload over respectable ranges and at reasonable speeds, which resulted in the 204 and subsequent 205 becoming the most successful western helicopter series in terms of numbers built.
The civil 204B was first delivered in 1961. The subsequent Model 205A-1 is equivalent to the UH-1H, which, compared to the 204, is longer, larger, and has better performance and a more powerful engine.
Over 60 civil Model 204B helicopters had been delivered by 1967, while further examples were built by Agusta-Bell until 1973. 12,000 Model 205s (including civil 205A-1s) were built by Bell and Agusta-Bell up to the early 1980s. Numerous ex-military 204s and 205s were converted for commercial use.
A Bell 205A-1, used by Royal Thai Police
Bell Helicopter's company designation of the UH-1B.
Bell 204B – Civil or military utility transport helicopter, derived from the UH-1B. Powered by a T53-09A, max weight was 8,500 lbs, max passengers, ten.
Agusta 204B – Civil or military utility transport helicopter. Built under licence in Italy by Agusta in 1963–1967. Also known as Agusta-Bell AB 204
Bell Helicopter's company designation of the UH-1H.
Bell 205A – Civil or military utility transport helicopter. Powered by one T53-11A, max weight 8,500 pounds, max passenger, 14.
Agusta-Bell 205 – Civil or military utility transport helicopter. Built under licence in Italy by Agusta.
Bell 205A-1 – Civil or military utility transport helicopter version, initial version based on the UH-1H. Powered by one T53-13A, max weight 9,500 pounds (10,500 for external loads), max passengers, 14.
Agusta-Bell 205A-1 – Modified version of the AB 205.
Fuji-Bell 205B – a joint Bell-Fuji commercial variant based on UH-1J, a Japanese improved model of UH-1H.
Bell 210 – Bell Helicopter's designation for a UH-1H, remanufactured and sold as a new aircraft. Powered by one T53-17B, same weight capacities as the 205B.
A Bell 205A-1 on firefighting duty with Valhalla Helicopters
Agusta-Bell 205BG – Prototype fitted with two Gnome H 1200 turboshaft engines.
Agusta-Bell 205TA – Prototype fitted with two Turbomeca Astazous turboshaft engines.
Bell 208 – In 1965, Bell experimented with a single twin-engine Model 208 "Twin Huey" prototype, which was a UH-1D fitted with Continental XT67-T-1 twin-pack engine module, consisting of two power turbines driving a common gearbox. This exercise was performed as an experiment using company funds.
205A-1++ – Field-upgraded 205A utilizing a T53-17 engine and a 212 drivetrain. Similar to the production 205B and 210.
Advanced 205B – Proposed upgraded Japanese version.
Global Eagle – Pratt & Whitney Canada name for a modified UH-1H with a new PT6C-67D engine, modified tail rotor, and other minor changes reported to increase range and fuel efficiency over the Bell 212.
Huey 800 – Upgraded commercial version, fitted with an LHTEC T800 turboshaft engine.
Bell 211 – The HueyTug, was a commercial version of the UH-1C with an upgraded transmission, longer main rotor, larger tailboom, strengthened fuselage, stability augmentation system, and a 2,650 shp (1,976 kW) T55-L-7 turboshaft engine.
Bell 212 – Bell Helicopter's company designation for the UH-1N.
Bell 214 Huey Plus – Strengthened development of the Bell 205 airframe with a larger engine; optimized for "hot and high" conditions. Later developed into the larger, twin-engine Bell 214ST.
Bell 412 – Bell 212 with a four-blade semi-rigid rotor system.
Panha Shabaviz 2-75 – is an Iranian utility helicopter built by the Iranian Helicopter Support and Renewal Company. It is a reverse engineered version of the Bell 205s which were sold to the government of Mohammad Reza Pahlavi. The first example was built in 1998 and the type was publicly unveiled the following year. It has been manufactured locally in Iran since 2002 and is in active service with the Iranian military and government. It has also been claimed that it can be modified to carry light weaponry.