User:Born2flie/UH-1 Iroquois

Main article: UH-1 Iroquois

This page is about the single-engine military versions of the Bell Model 204 and 205. For the civil versions, see Bell 204/205. For twin-engine military models, see UH-1N Twin Huey. For the U.S. Marine Corps' latest variant, see UH-1Y Venom. For an overview of the whole Huey family of aircraft, see Bell Huey family.

UH-1 Iroquois
U.S. Army Bell UH-1D Iroquois
Role	Multipurpose utility helicopter
Manufacturer	Bell Helicopter
First flight	22 October 1956 (XH-40)
Introduction	1959
Primary users	United States Army Japan Ground Self-Defense Force Australian Army Philippine Air Force
Number built	>16,000
Variants	UH-1N Twin Huey AH-1 Cobra Bell 204/205 Bell 212 Bell 214

The UH-1 Iroquois is a military helicopter powered by a single, turboshaft engine, with a two-bladed main rotor and tail rotor. The helicopter was developed by Bell Helicopter as the Model 204 to meet the United States Army's requirement for a medical evacuation and utility helicopter in 1952, and first flew on 20 October 1956. Ordered into production in March 1960, the UH-1 was the first turbine-powered helicopter to enter production for the United States military, and remained in production until 1976, with more than 16,000 produced worldwide.

The first combat service of the UH-1 was by the U.S. Army during the Vietnam War. The original designation of HU-1 led to the helicopter's nickname of Huey. In September 1962, the designation was changed to UH-1, but the nickname remained both unofficially in common use, and officially in use by the United States Marine Corps.

Development

Main article: UH-1 Iroquois variants

The XH-40 would become the UH-1

In 1952, the Army identified a requirement for a new helicopter to serve as medical evacuation (MEDEVAC), instrument trainer and general utility aircraft. The Army determined that current helicopters were too large, underpowered, or were too complex to maintain easily. In November 1953, revised military requirements were submitted to the Department of the Army. 20 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. On 23 February 1955, the Army announced its decision, selecting Bell to build three copies of the Model 204 for evaluation, designated as the XH-40.

Model 204

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 Forth Worth, Texas, with Bell's chief test pilot, Floyd Carlson, at the controls. 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. In March 1960, the Army awarded Bell a production contract for 100 aircaft, which was designated as the HU-1A and officially named Iroquois, after the native American nations.

The helicopter quickly developed a nickname derived from its designation of HU-1, which came to be pronounced as "Huey". The reference quickly became so popular that Bell began casting the name on the helicopter's anti-torque pedals. The official U.S. Army name was almost never used in practice. 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.

The service tests of the YH-40, while glowing in praise for the helicopter's advances over piston-engined helicopters, had proven it to be under-powered with a production T53-L-1A powerplant producing a maximum continuous 770 shaft horsepower (570 kW), and indicated the need for improved, follow-on models even as the first UH-1As were being delivered. Subsequently, Bell proposed the UH-1B, an improved model equipped with the Lycoming T53-L-5 engine, with 960 shp (720 kW) and a longer cabin that could accommodate seven passengers, or four stretchers and a medical attendant. Army testing of the UH-1B started in November 1960, with the first production aircraft arriving in March 1961.

Bell commenced development of the UH-1C in 1960, to correct aerodynamic deficiencies of the armed UH-1B. Bell fitted the UH-1C with a 1,100 shp (820 kW) T53-L-11 engine to provide the power needed to lift the weapons systems, either in use or under development at the time. The UH-1B aircraft would later be retrofitted with the same engine. A new rotor system was developed to allow higher airspeeds and reduce the incidence of retreating blade stall during diving engagements. The increased power and a larger diameter rotor required Bell's engineers to design a new tailboom for the UH-1C, which incorporated a wider chord fin on a longer boom and larger synchronized elevators.

Bell also introduced a dual hydraulic control system for redundancy in battle and an improved inlet filter system for the dusty conditions found in southeast Asia. The UH-1C fuel capacity was increased to 242 US gallons (920 L) and gross weight was raised to 9,500 lb (4,300 kg), giving a nominal useful load of 4,673 lb (2,120 kg). UH-1C production started in June 1966, and total of 766 aircraft were completed, including five for the Royal Australian Navy, designated "N9" and five for Norway.

Model 205

While earlier "short-body" Hueys were a success, the Army wanted a version that could carry a crew of four (two pilots and two door gunners) and also deliver an infantry section of 8-10 soldiers. Bell's solution was to stretch the HU-1B fuselage by 41 inches (105 cm) and use the extra space to fit four seats next to the transmission, facing out. This brought the total seating capacity to 15, including the crew. The enlarged cabin could also accommodate six stretchers, double that of the earlier models, making it a more capable MEDEVAC aircraft. In place of the earlier model's sliding side doors with a single window, larger doors were fitted which had two windows, plus a small hinged panel with an optional window, providing access to the cabin. The doors and hinged panels were quickly removable, allowing the Huey to be flown in a "doors off" configuration.

The Model 205 prototype flew on 16 August 1960. Seven pre-production/prototype aircraft were delivered and tested at Edwards AFB starting in March 1961. The 205 was initially equipped with a 44-foot (13.4 m) main rotor and a Lycoming T53-L-9 engine with 1,100 shp (820 kW). The rotor was lengthened to 48 feet (14.6 m) with a chord of 21 inches (53 cm). The tailboom was also lengthened, in order to accommodate the longer rotor blades. Altogether, the modifications resulted in a gross weight capacity of 9,500 pounds (4,300 kg). The Army ordered production of the 205 in 1963, produced with a T53-L-11 engine for its multi-fuel capability. The prototypes were designated as YUH-1D and the production aircraft was designated as the UH-1D.

Marine Corps

In 1962, the Marines held a competition to choose an assault support helicopter to replace the Cessna O-1 fixed-wing aircraft and the Kaman OH-43D helicopter. The winner was the UH-1B, which was already in service with the Army. The helicopter was designated the UH-1E and modified to meet Marine requirements. The major changes included the use of all-aluminum construction for corrosion resistance, radios compatible with Marine Corps ground frequencies, a rotor brake for shipboard use–to stop the rotor quickly on shutdown–and a roof-mounted rescue hoist.

The UH-1E was first flown on 7 October 1963, and deliveries commenced 21 February 1964, with 192 aircraft completed. Due to production line realities at Bell, the UH-1E was produced in two different versions, both with the same UH-1E designation. The first 34 built were essentially UH-1B airframes with the Lycoming T53-L-11 engine producing 1,100 shp (820 kW). When Bell switched production to the UH-1C, the UH-1E production benefitted from the same changes. The Marine Corps later upgraded UH-1E engines to the Lycoming T53-L-13, which produced 1,400  shp (1,000 kW), after the Army introduced the UH-1M and upgraded their UH-1C helicopters to the same engine.

Air Force

The United States Air Force's (USAF) competition for a helicopter to be used for support on missile bases included a specific requirement to mandate the use of the General Electric T58 turboshaft as a powerplant. The Air Force had a large inventory of these engines on hand for its fleet of HH-3 Jolly Green Giant rescue helicopters and using the same engine for both helicopters would save costs. In response, Bell proposed an upgraded version of the 204B with the T58 engine. Because the T58 was mounted in front of the transmission on the S-61R, it had to be mounted "backwards" with its exhaust rerouted to the back of the aircraft.

On 7 June 1963, the Air Force named Bell Helicopter as the winner. Originally designated the H-48, it was later designated as the UH-1F. A TH-1F trainer was also built for the USAF, with the first TH-1F flown in January 1967, followed by delivery of 27 aircraft from April to July of that year. In Italy, Agusta produced a model similar to the UH-1F by re-engining the 204B with the 1,225 shp (914 kW) Rolls-Royce Gnome turboshaft and later the UH-1F's General Electric engine. The Italian version was exported to the military of the Netherlands, Denmark, Austria, and Switzerland.

Design

The UH-1 is a general utility helicopter. It has a metal fuselage of semi-monocoque construction with tubular landing skids and two rotor blades on the main rotor. Early UH-1 models featured a single Lycoming T53 turboshaft engine in versions with power ratings from 700 shp (522 kW) to 1,400 shp (1,040 kW). Later UH-1 and related models would feature twin engines and four-blade rotors.

All aircraft in the UH-1 family have similar construction. The most-produced version, the UH-1H, is representative of all types, particularly the long-body versions. The main structure consists of two longitudinal main beams that run under the passenger cabin to the nose and back to the tail boom attachment point. The main beams are separated by transverse bulkheads and provide the supporting structure for the cabin, landing gear, under-floor fuel tanks, the transmission, engine and tail boom. The main beams are joined at the lift beam, a short aluminum girder structure that is attached to the transmission via a lift link on the top and the cargo hook on the bottom and is located at the aircraft's centre of gravity. The lift beams were changed to steel later in the UH-1H's life, due to cracking on high-time airframes. Both the fuselage and the tail boom are of a semi-monocoque design. The tail boom attaches to the fuselage with four bolts.

The UH-1H's dynamic components include the engine, transmission, rotor mast, main rotor blades, tail rotor driveshaft, 42 degree and 90 degree gearboxes. The transmission is of a planetary type and reduces the T53-L13B engine's output to 324 rpm at the main rotor. The two-bladed, semi-rigid rotor design, with pre-coned and under-slung blades, is a development of early Bell model designs, such as the Bell 47 with which it shares common design features, including a dampened stabilizer bar. The two-bladed system reduces storage space required for the aircraft, but at a cost of higher vibration levels. The two-bladed design also is responsible for the characteristic 'Huey thump' when the aircraft is in flight, which is particularly evident during descent and in turning flight. The tail rotor is driven from the main transmission, via the two directional gearboxes which provide a tail rotor speed approximately six times that of the main rotor to increase tail rotor effectiveness.

The UH-1H also features a synchronised elevator on the tail boom, which is linked to the cyclic control and allows a wider centre of gravity range. The standard fuel system consists of five interconnected fuel tanks, three of which are mounted behind the transmission and two of which are under the cabin floor. The landing gear consists of two arched cross tubes joining the skid tubes. The skids have replaceable sacrificial skid shoes to prevent wear of the skid tubes themselves. Skis and inflatable floats may be fitted.

Internal seating is made up of two pilot seats and seating for up to 13 passengers or crew in the cabin. The maximum seating arrangement consists of a four man bench seat facing rearwards behind the pilot seats facing a five man bench seat in front of the transmission structure. Beside the transmission structure on either side of the aircraft are two two-man bench seats, facing outwards. All passenger seats are aluminium tube with canvas seat material and are quickly removable and reconfigurable. The UH-1H is rarely capable of lifting 15 people, except at very low density altitudes, fuels loads, and hovering heights and so fewer seats are usually fitted. The cabin may also be configured for up to six stretchers, an internal rescue hoist, auxiliary fuel tanks, spotlights or many other mission kits. Access to the cabin is via two aft-sliding doors and two small forward hinged panels. The doors and hinged panels may be removed for flight or the doors may be pinned open. Pilot access is via individual hinged doors.

While the five main fuel tanks are self-sealing, the UH-1H was not equipped with factory armour, although armoured pilot seats were available.

The UH-1H's dual controls are conventional for a helicopter and consist of a single hydraulic system boosting the cyclic stick, collective lever and anti-torque pedals. The collective levers have integral throttles, although these are not used to control rotor rpm, which is automatically governed, but are used for starting and shutting down the engine. The cyclic and collective control the main rotor pitch through torque tube linkages to the swash plate, while the anti-torque pedals change the pitch of the tail rotor via a tensioned cable arrangement. Some UH-1Hs have been modified to replace the tail rotor control cables with torque tubes similar to the UH-1N Twin Huey.

Aircraft markings

UH-1Hs used for ferrying VIPs into Panmunjom in the DMZ area between North and South Korea used three 12" wide Yellow stripes vertically over the fuselage. It signified unarmed aircraft carrying UNCMAC members.

Operational history (draft)

UH-1s tasked with a ground attack or armed escort role were outfitted with rocket launchers, grenade launchers, and machine guns as gunships. These armed helicopters were commonly referred to as Frogs or Hogs if they carried rockets, and Cobras or simply Guns if they had guns. UH-1s tasked and configured for troop transport were often called Slicks due to an absence of weapons pods, although crewmembers manned machine guns on either side. Navy and Marine Corps aircraft used as gunships were referred to as Sharks and troop transports were referred to as Dolphins.

United States

Production UH-1A helicopters first entered service with the 101st Airborne at Fort Lewis, Washington, the 82nd Airborne Division, and the 57th Medical Detachment. Although they were intended for evaluation only, the Army quickly pressed them into operational service. The 57th Medical Detachment arrived in Vietnam in March 1962. The next UH-1 unit to arrive in Vietnam after the 57th Medical Detachment was a new test unit, the U.S. Army's Utility Tactical Transport Company (UTTCO). UTTCO had 20 UH-1As and deployed to Vietnam in Fall 1962. These aircraft were used as armed escorts to the existing H-21 Shawnees and H-34 Choctaws troop carriers. The first deployment of the UH-1B occurred the following year when 11 aircraft were sent to Vietnam in November 1963, to join the UH-1A models already in use by UTTCO.

The first Army unit deliveries of the UH-1D occurred on 9 August 1963, when the 11th Air Assault Division (Test) at Fort Benning Georgia received two. This unit was eventually reorganized into the 1st Cavalry Division and deployed to Vietnam with the UH-1D in 1965.

The Army received delivery of the first production UH-1H in September 1967, with 4,850 eventually delivered in total. The UH-1H would serve as the mainstay of the Army utility helicopter fleet until the arrival of the UH-60 Black Hawk.

Air Force

The UH-1F was introduced into the USAF inventory on February 20 1964. The USAF took delivery of 119, with production ending in 1967. Many of the aircraft served in southeast Asia with the 20th Special Operations Squadron and some were converted to the armed UH-1P configuration.

The last UH-1F was retired from the USAF in the early 1980s when it was replaced by the UH-1N. many of these aircraft later served as forest fire fighting aircraft with various US state governments and agencies. There was a TH-1F trainer also built for the USAF. The first TH-1F was flown in January 1967 and deliveries ran from April to July of that year with 27 completed.

Navy

With deliveries already underway to the Marine Corps, the United States Navy tested the UH-1E and found the aircraft acceptable for use as a utility helicopter. On 16 May 1968, the Navy ordered eight aircraft under the designation UH-1L. The UH-1L was basically a UH-1E, but equipped with a rescue hoist and intake particle screen. The aircraft were delivered without armor or armament installed, and were also equipped with the Lycoming T53-L-13 engine.

The first four aircraft were delivered in November 1969, and sent to Vietnam to equip the Navy's HA(L)-3 detachment assigned to Operation Sealords. In Vietnam, the aircraft were modified with weapons and armor, including provisions to carry 500-pound high-explosive bombs and Fuel-Air Explosive munitions.

A training version of the UH-1L, designated TH-1L, was produced for the Navy to replace the H-34 and the borrowed Army UH-1Ds used in the training role. Forty-five TH-1Ls were delivered starting in November 1969.

Bell was also awarded a contract by the United States Navy in December 1968, for a new search and rescue helicopter. The aircraft was designated the HH-1K and was also a variant of the UH-1E, with different avionics and the 1,400 shaft horsepower Lycoming T53-L-13 engine. Deliveries of the HH-1K started in May 1970, and by November, three had been sent to Vietnam to serve with US Navy squadron HA(L)-3. A total of 27 HH-1Ks were produced for the Navy.

Argentina

UH-1Hs at Port Stanley Airport

Nine Argentine Army UH-1Hs and two Argentine Air Force Bell 212 were included with the aircraft deployed during the Falklands War (Spanish: Guerra de las Malvinas). The aircraft were used for general transport and SAR missions, and were based at Port Stanley (BAM Puerto Argentino). Two of the Hueys were destroyed and the balance were captured by the British. At least three of the aircraft were reused by the British to ferry supplies and troops but had to be painted to avoid confusion..

656 Sqn, AAC and 820 NAS operated these captured UH-1s. The captured UH-1H AE-409 is now in the Museum of Army Flying at Middle Wallop. UH-1H AE-422 is in the Fleet Air Arm Museum, Yeovilton. One of these UH-1Hs was civil registered as G-HUEY in the UK and participated in a number of airshows, and in the James Bond movie "The Living Daylights" (1987) as medevac.

Australia

The Australian Army assigned UH-1H helicopters to RAAF No. 9 Squadron. The Squadron deployed to South Vietnam in mid-1966, as part of the 1st Australian Task Force. The Australian UH-1s were used for troop transport and medical evacuation. In 1969, four of the helicopters were converted to gunships, which the troops called Bushrangers, and were armed with an M134 7.62 mm minigun and a 7-round rocket pod mounted on each side.

From 1982 to 1986, the Squadron contributed aircraft and aircrew to the Australian helicopter detachment which formed part of the Multinational Force and Observers peacekeeping force in the Sinai Peninsula, Egypt.

Canada

Ten UH-1H were sold to the government of Canada for use under the designation CUH-1H with the first one being delivered on 6 March 1968. The aircraft were evaluated by the Canadian Forces and found unsuitable for tactical use. In response, the Canadian government sponsored the development of the twin-engined version of the "Hotel", the UH-1N Twin Huey. The CUH-1Hs were modified for search and rescue duties, redesignated CH-118, and served until 1995, when they were replaced by the CH-146 Griffon.

El Salvador

During its civil war El Salvador received about 80 UH-1H and 24 UH-1M from the United States, as part of the aid to fight the guerrillas between 1979 and 1992. These helicopters were heavily engaged in combat, supporting the army in fighting guerrillas throughout the country. As a result many were shot down. After the war only 20 UH-1H and 14 UH-1M survived, most of them scrapped a few years later.

These helicopters were operated by El Salvador Air Force, being at its time the biggest and most experienced combat helicopter force in Central and South America, fighting during 10 years and being trained by US Army in tactics developed during the Vietnam war. Gunship UH-1M helicopters used by El Salvador were modified to carry bombs instead of rocket pods. UH-1Hs were also used as improvised bombers.

Lebanon

During the battle of Nahr el-Bared camp in North Lebanon, the Lebanese army, lacking fixed-wing aircraft, modified the UH-1H allowing it to carry 500 lb (227 kg) Mark 82 bombs to strike militant positions. Each Huey was equipped on each side with special mounts engineered by the Lebanese army, to carry the high explosive bombs. (See Helicopter bombing.)

Rhodesia

Very late in the Rhodesian Civil War the Rhodesian Air Force was able to obtain and use eleven Bell UH-1 Iroquois, known in service as Cheetahs. The aircraft were ordered new from Augusta via Kuwait and then shipped to Lebanon, where a local Christian militia swapped them for worn-out ex-Israeli machines, prior to delivery. After much work these then formed No. 8 Sqn Rhodesian Air Force and took part as troop transports in the counter-insurgency fight. One was lost in combat in September 1979, when hit in Mozambique by a RPG. At least other three were lost. The survivors were put up for sale in 1990.

Israel

The Israeli Air Force was another prominent operator of the UH-1, using it for over thirty years in various different conflicts against both the armies of Arab countries and Palestinian militants. Israel's first Hueys were UH-1Ds, delivered from the United States in October 1968 under arms shipments via the administration of Lyndon Johnson. Israel also acquired Italian UH1s license made by Augusta as well. In total, Israel acquired 64 UH-1s of different models.

The UH-1s were used throughout the 1970s and 1980s, first seeing action against Egypt during the War Of Attrition. During the Yom Kippur War, UH-1s assisted in the transport of Israeli ground troops throughout the Sinai and Golan Heights against both Egyptian and Syrian troops. In an act of desperation, they were also used with other helicopters to spot Egyptian and Syrian surface to air missile batteries for fighter aircraft, a process that was quickly discontinued and never used again. Israeli UH-1s would go on to see their final combat in Lebanon, delivering Israeli troops and supplies in the fight against the PLO, Syria, and later Hezbollah.

Israel withdrew its UH-1s from service in 1991, after thirty three years of service. They were replaced by Sikorsky UH-60 Blackhawk helicopters given to Israel after complying with the United States and Britain for not retaliating against Iraqi Scud missile attacks. Some were passed on to pro Israeli militias in Lebanon, and others to logging companies in Singapore. Some Israeli UH-1s also arrived in the hands of the Rhodesian Air Force as well.

Operational history

The UH-1 has been widely exported and remains in front line service in a number of countries.

United States

Troops exiting from a UH-1D Iroquois.

Army

The HU-1A (later redesignated UH-1A) first entered service with the 101st Airborne Division at Fort Campbell, Kentucky, the 82nd Airborne Division, and the 57th Medical Detachment. Although intended for evaluation only, the Army quickly pressed the new helicopter into operational service and Hueys with the 57th Medical Detachment arrived in Vietnam in March 1962.

The UH-1 has long been a symbol of US involvement in Southeast Asia in general and Vietnam in particular, and as a result of that conflict, has become one of the world's most recognized helicopters. In Vietnam primary missions included general support, air assault, cargo transport, aeromedical evacuation, search and rescue, electronic warfare, and later, ground attack. During the conflict, the craft was upgraded, notably to a larger version based on the Model 205. This version was initially designated the UH-1D and flew operationally from 1963.

UH-1Ds airlift soldiers to a new staging area

During service in the Vietnam War, the UH-1 was used for various purposes and various terms for each task abounded. UH-1s tasked with a ground attack or armed escort role were outfitted with rocket launchers, grenade launchers, and machine guns. These gunship UH-1s were commonly referred to as Frogs or Hogs if they carried rockets, and Cobras or simply Guns if they had guns. UH-1s tasked and configured for troop transport were often called Slicks due to an absence of weapons pods. Slicks did have door gunners, but were generally employed in the troop transport and medevac roles. In the US Navy and USMC the gunships were referred to as Sharks and troop transport aircraft as Dolphins. Towards the end of the war, the UH-1 was tested with TOW missiles, and two UH-1B helicopters equipped with the XM26 Armament Subsystem were deployed to help counter the 1972 Easter Invasion.

Two Navy UH-1B Huey gunships on the deck of USS Garrett County (AGP-786), in the Mekong Delta, South Vietnam

UH-1s also flew hunter-killer teams with observation helicopters, namely the Bell OH-58A Kiowa and the Hughes OH-6 Cayuse (Loach).

UH-1 troop transports were designated by Blue teams, hence the nickname for troops carried in by these Hueys as the Blues. The reconnaissance or observation teams were White teams. The attack ships were called Red teams. Over the duration of the conflict the tactics used by the military evolved and teams were mixed for more effective results. Purple teams with one or two Blue slicks dropping off the troops, while a Red attack team provided protection until the troops could defend themselves. Another highly effective team was the Pink Recon/Attack team, which offered the capability of carrying out assaults upon areas where the enemy was known to be present but could not be pinpointed.

During the course of the war, the UH-1 went through several upgrades. The UH-1A, B, and C models (short fuselage, Bell 204) and the UH-1D and H models (stretched-fuselage, Bell 205) each had improved performance and load-carrying capabilities. The UH-1B and C performed the gunship and some of the transport duties until 1967, when the new AH-1 Cobra arrived on the scene. The newer Cobra, a purpose-built attack helicopter based on the UH-1 was faster, sleeker, harder to hit, and could carry more ordnance. The increasing intensity and sophistication of NVA anti-aircraft defenses made continued use of gunships based on the UH-1 impractical, and after Vietnam the Cobra was adopted as the Army's main attack helicopter. Devotees of the UH-1 in the gunship role cite its ability to act as an impromptu dustoff if the need arose, as well as the superior observational capabilities of the larger Huey cockpit, which allowed return fire from door gunners to the rear and sides of the aircraft.

During the war 3,305 UH-1 were destroyed. In total 2,202 Huey pilots were killed and approximately 2,500 aircraft were lost, roughly half to combat and the rest to operational accidents.

The US Army phased out the UH-1 with the introduction of the UH-60 Black Hawk, although the Army UH-1 Residual Fleet has around 700 UH-1s that were to be retained until 2015. Army support for the craft was intended to end in 2004.

Air Force

In October 1965, the USAF 20th Helicopter Squadron was formed at Tan Son Nhut Air Base in South Vietnam. Initially equipped with CH-3C helicopters, the UH-1F and UH-1P were added to the unit's inventory by June 1967. At the end of 1967, the unit relocated from Tan Son Nhut to Nakhon Phanom Royal Thai Air Force Base, and the CH-3 helicopters were transferred to the 21st Helicopter Squadron. On 1 August 1968, the unit was designated as the 20th Special Operations Squadron. The Squadron's UH-1s became known as the "Green Hornets" from their predominately green, two-tone camouflage and the unit's radio call sign, "Hornet". The Squadron's main role was to insert, extract, and provide cover for reconnaissance teams, and to conduct psychological warfare and other support roles for covert operations, especially in Laos and Cambodia.

On 26 November 1968, USAF First Lieutenant James P. Fleming piloted a UH-1F to rescue a team of six Special Forces soldiers who were under heavy attack. He was later awarded the Medal of Honor for the rescue.

Variants (draft)

U.S. Military

XH-40

The initial Bell 204 prototype. Three prototypes were built, equipped with the Lycoming XT-53-L-1 engine of 700 shp.

YH-40

Six pre-production aircraft. One maintained at the Bell facility (referred to as YH-40-BF), one sent to Eglin AFB for climactic testing, one to Edwards AFB for testing, three to Fort Rucker for Army trials.

Bell Model 533

One YH-40 rebuilt as a high-performance flight test aircraft with turbofan engines and wings.

UH-1A

Initial Bell 204 production model, originally designated as HU-1A prior to 1962.

XH-1A

A single UH-1A was redesignated for grenade launcher testing in 1960.

UH-1B

Upgraded HU-1A, various external and rotor improvements. Originally designated HU-1B prior to 1962.

NUH-1B

a single test aircraft, serial number 64-1861.

UH-1C

UH-1B with improved engine, modified blades and rotor-head for better performance in the gunship role.

YUH-1D

Seven pre-production prototypes of the UH-1D.

UH-1D

Initial Bell 205 production model (long fuselage version of the 204). Designed as a troop carrier to replace the CH-34 then in US Army service.

HH-1D

Army crash rescue variant of UH-1D.

UH-1E

UH-1B/C for USMC with different avionics and equipment.

NUH-1E

UH-1E configured for testing.

TH-1E

UH-1C configured for Marine Corps training. Twenty were built in 1965.

UH-1F

Model 204B for USAF with General Electric T-58-GE-3 engine of 1,325 shp. Due to the configuration of the T58 engine, Bell installed the engine backwards. The HH-3's engines are in front of the transmission, whereas the UH-1's engine is behind the transmission. Externally, the only visible differences from UH-1B were the engine exhaust, which exited to the right side of the engine and the longer tail boom.

TH-1F

Trainer based on the UH-1F for the USAF.

UH-1G

UH-1D/H gunships operating with the Cambodia armed forces were locally given the designation UH-1G.

UH-1H

Improved UH-1D with a Lycoming T-53-L-13 engine of 1,400 shp.

CUH-1H

Canadian Forces designation for the UH-1H utility transport helicopter. Redesignated CH-118.

EH-1H

Twenty-two aircraft converted by installation of AN/ARQ-33 radio intercept and jamming equipment.

HH-1H

SAR variant for the USAF with rescue hoist.

JUH-1

Five UH-1Hs converted to SOTAS battlefield surveillance configuration with belly-mounted airborne radar.

TH-1H

Recently modified UH-1Hs for use as basic helicopter flight trainers by the USAF.

UH-1J

An improved Japanese version of the UH-1H built under license in Japan by Fuji was locally given the designation UH-1J.

HH-1K

Purpose built SAR variant of the Model 204 for the US Navy with USN avionics and equipment.

TH-1L

Helicopter flight trainer based on the HH-1K for the USN. Forty-five were built.

UH-1L

Utility variant of the TH-1L. Eight were built.

UH-1M

Gunship specific UH-1C upgrade with Lycoming T-53-L-13 engine of 1,400 shp.

UH-1N

Initial Bell 212 production model, the Bell "Twin Pac" twin-engined Huey.

UH-1P

UH-1F variant for USAF for special operations use and attack operations used soley by the USAF 20th Special Operations Squadron, "the Green Hornets".

UH-1U

Single prototype for Counter Mortar/Counter Battery Radar Jamming aircraft. Crashed at Edwards AFB during testing.

UH-1V

Aeromedical evacuation, rescue version for the US Army.

EH-1X

Ten Electronic warfare UH-1Hs converted under "Quick Fix IIA".

UH-1Y

Upgraded variant developed from existing upgraded late model UH-1Ns, with additional emphasis on commonality with the AH-1Z.

Other militaries

Bell 204

Bell Helicopters company designation, covering aircraft from the XH-40, YH-40 prototypes to the UH-1A, UH-1B, UH-1C, UH-1E, UH-1F, HH-1K, UH-1L, UH-1P and UH-1M production aircraft.

Agusta-Bell AB 204

Military utility transport helicopter. Built under licence in Italy by Agusta.

Agusta-Bell AB 204AS

Anti-submarine warfare, anti-shipping version of the AB 204 helicopter.

Fuji-Bell 204B-2

Military utility transport helicopter. Built under licence in Japan by Fuji Heavy Industries. Used by the Japan Ground Self Defence Force under the name Hiyodori.

Bell 205

Bell Helicopters company designation of the UH-1D and UH-1H helicopters.

Bell 205A-1

Military utility transport helicopter version, initial version based on the UH-1H.

Bell 205A-1A

As 205A-1, but with armament hardpoints and military avoinics. Produced specifically for Israeli contract.

Agusta-Bell 205

Military utility transport helicopter. Built under licence in Italy by Agusta.

Fuji-Bell 205A-1

Military utility transport helicopter. Built under licence in Japan by Fuji. Used by the Japanese Ground Self Defence Force under the designation HU-1H.

Bell Huey II

A modified and re-engined UH-1H, significantly upgrading its performance, and its cost-effectiveness. Currently offered by Bell to all current military users of the type.

Variants

Main article: UH-1 Iroquois variants

U.S. Military variants

UH-1A Iroquois hovering

• XH-40: The initial Bell 204 prototype. Three prototypes were built, equipped with the Lycoming XT-53-L-1 engine of 700 shp.
• YH-40: Six aircraft for evaluation, as XH-40 with 12-inch cabin stretch and other modifications.
  • Bell Model 533: One YH-40BF rebuilt as a flight test bed with turbofan engines and wings.
• HU-1A: Initial Bell 204 production model, redesignated as the UH-1A in 1962. 182 built.
  • TH-1A: UH-1A with dual controls and blind-flying instruments, 14 conversions.
  • XH-1A: A single UH-1A was redesignated for grenade launcher testing in 1960.
• HU-1B: Upgraded HU-1A, various external and rotor improvements. Redesignated UH-1B in 1962. 1014 built plus four prototypes designated YUH-1B.
  • NUH-1B: a single test aircraft, serial number 64-18261.
• UH-1C: UH-1B with improved engine, modified blades and rotor-head for better performance in the gunship role. 767 built.
• YUH-1D: Seven pre-production prototypes of the UH-1D.
• UH-1D: Initial Bell 205 production model (long fuselage version of the 204). Designed as a troop carrier to replace the CH-34 then in US Army service. 2008 built many later converted to UH-1H standard.
  • HH-1D: Army crash rescue variant of UH-1D.
• UH-1E: UH-1B/C for USMC with different avionics and equipment. 192 built.
  • NUH-1E: UH-1E configured for testing.
  • TH-1E: UH-1C configured for Marine Corps training. Twenty were built in 1965.
• UH-1F: UH-1B/C for USAF with General Electric T-58-GE-3 engine of 1,325 shp. 120 built.
  • TH-1F: Instrument and Rescue Trainer based on the UH-1F for the USAF. 26 built.

CH-118 Iroquois helicopters at CFB Moose Jaw, 1982

• UH-1H: Improved UH-1D with a Lycoming T-53-L-13 engine of 1,400 shp. 5435 built.
  • CUH-1H: Canadian Forces designation for the UH-1H utility transport helicopter. Redesignated CH-118. 10 built.
  • EH-1H: Twenty-two aircraft converted by installation of AN/ARQ-33 radio intercept and jamming equipment for Project Quick Fix.
  • HH-1H: SAR variant for the USAF with rescue hoist. 30 built.
  • JUH-1: Five UH-1Hs converted to SOTAS battlefield surveillance configuration with belly-mounted airborne radar.
  • TH-1H: Recently modified UH-1Hs for use as basic helicopter flight trainers by the USAF.
• UH-1G: Unofficial name applied locally to at least one armed UH-1H by Cambodia.
• UH-1J: An improved Japanese version of the UH-1H built under license in Japan by Fuji was locally given the designation UH-1J. Among improvements were an Allison T53-L-703 turboshaft engine providing 1,343 kW (1,800 shp), a vibration-reduction system, infrared countermeasures, and a night-vision-goggle (NVG) compatible cockpit.
• HH-1K: Purpose built SAR variant of the Model 204 for the US Navy with USN avionics and equipment. 27 built.
• TH-1L: Helicopter flight trainer based on the HH-1K for the USN. Forty-five were built.
  • UH-1L: Utility variant of the TH-1L. Eight were built.
• UH-1M: Gunship specific UH-1C upgrade with Lycoming T-53-L-13 engine of 1,400 shp.
• UH-1N: Initial Bell 212 production model, the Bell "Twin Pac" twin-engined Huey.
• UH-1P: UH-1F variant for USAF for special operations use and attack operations used solely by the USAF 20th Special Operations Squadron, "the Green Hornets".
• EH-1U: No more than 2 UH-1H aircraft modified for Multiple Target Electronic Warfare System (MULTEWS).
• UH-1V: Aeromedical evacuation, rescue version for the US Army.
• EH-1X: Ten Electronic warfare UH-1Hs converted under "Quick Fix IIA".
• UH-1Y: Upgraded variant developed from existing upgraded late model UH-1Ns, with additional emphasis on commonality with the AH-1Z.

Other military variants

• Bell 204: Bell Helicopters company designation, covering aircraft from the XH-40, YH-40 prototypes to the UH-1A, UH-1B, UH-1C, UH-1E, UH-1F, HH-1K, UH-1L, UH-1P and UH-1M production aircraft.
  • Agusta-Bell AB 204: Military utility transport helicopter. Built under license in Italy by Agusta.
  • Agusta-Bell AB 204AS: Anti-submarine warfare, anti-shipping version of the AB 204 helicopter.
  • Fuji-Bell 204B-2: Military utility transport helicopter. Built under license in Japan by Fuji Heavy Industries. Used by the Japan Ground Self-Defense Force under the name Hiyodori.

• Bell 205: Bell Helicopters company designation of the UH-1D and UH-1H helicopters.
  • Bell 205A-1: Military utility transport helicopter version, initial version based on the UH-1H.
  • Bell 205A-1A: As 205A-1, but with armament hardpoints and military avionics. Produced specifically for Israeli contract.
  • Agusta-Bell 205: Military utility transport helicopter. Built under license in Italy by Agusta.
• AIDC UH-1H: Military utility transport helicopter. Built under license in Taiwan by Aerospace Industrial Development Corporation.
• Dornier UH-1D: Military utility transport helicopter. Built under license in Germany by Dornier Flugzeugwerke.
  • Fuji-Bell 205A-1: Military utility transport helicopter. Built under licence in Japan by Fuji. Used by the Japanese Ground Self Defence Force under the designation HU-1H.

• Bell Huey II: A modified and re-engined UH-1H, significantly upgrading its performance, and its cost-effectiveness. Currently offered by Bell to all current military users of the type.

• UH-1/T700 Ultra Huey: Upgraded commercial version, fitted with a 1,400-kW (1900-shp) General Electric T700-GE-701C turboshaft engine.

Operators

Main article: List of UH-1 Iroquois operators

Afghanistan Albania Australia Austria Bahrain Bangladesh Belize Bolivia Bosnia and Herzegovina Brazil Brunei Burma Cambodia Canada Chile Colombia Costa Rica Dominican Republic El Salvador

Ecuador Ethiopia Germany Greece Georgia Guatemala Honduras Indonesia Iran Iraq Israel Italy Jamaica Japan Jordan Kuwait Lebanon North Macedonia Mexico

Morocco Netherlands New Zealand Norway Oman Pakistan Panama Paraguay Papua New Guinea Peru Philippines Republic of China (Taiwan) Rhodesia Saudi Arabia Senegal Singapore Serbia Somalia South Korea

South Vietnam Spain Sweden Tanzania Thailand Tunisia Turkey Uganda United Arab Emirates United States Uruguay Venezuela Vietnam Yemen Zambia Zimbabwe

Aircraft on display

A UH-1P on display

A UH-1H on display at an airshow

The UH-1 experienced a production number in the thousands (both short and long-frame types), and invariably a large number exist in flyable condition in nations around the world. A large number of decommissioned and retired aircraft exist as "gate guards" to various military bases, in aviation museums, and other static-display sites. Examples include:

• The Bell UH-1H "Smokey III" that resides in the Steven F. Udvar-Hazy Center served four tours and over 2,500 hours in Vietnam.
• UH-1A located at the Intrepid Sea-Air-Space Museum in New York City, currently under refurbishment.
• A Huey forms part of the collection in the American Air Force Hangar of the Imperial War Museum at Duxford near Cambridge, England.
• A fully refurbished UH-1 "Huey" is located in the Frontiers of Flight Museum in Dallas, Texas.
• The UH-1A formerly used as Command and Control aircraft for Gen William C. Westmoreland while he was commander of the 101st Airborne Division and Ft. Campbell, Ky is located in front of 101st Airborne Division Headquarters.
• UH-1B on static display at the Ft. Campbell, Kentucky museum. Also, an UH-1H is displayed at main entrance of 101st Airborne Division barracks.
• UH-1H formerly assigned to the Illinois Army National Guard on static display at the Prairie Aviation Museum located at the Central Illinois Regional Airport in Bloomington, Illinois.
• UH-1C/M on display on a stand at the entrance of the Tennessee National Guard Training Center at the Smyrna Airport (Tennessee) in Smyrna, Tennessee.
• UH-1's of various models on stands at the entrances of Fort Rucker, Alabama as well as at the Ft Rucker museum.
• Canadian CH-118 (UH-1H) 118101 at the National Air Force Museum of Canada, CFB Trenton, Ontario
• The Heartland Museum of Military Vehicles near Lexington, Nebraska, has a UH-1 visible from Interstate 80 as it passes by the museum. The display includes a sculptural representation of the iconic 1975 rooftop evacuation of the U.S. embassy in Saigon, Vietnam.
• The Cole Land Transportation Museum in Bangor, Maine, has a UH-1D on static display as part of the Vietnam Memorial. The display is visible from Interstate 395.
• UH-1 on display, War Memorial Park, Hopkinsville, Kentucky.
• Two UH-1s on display at the Mississippi Armed Forces Museum, Camp Shelby, Hattiesburg, Mississippi, One aircraft is a Medevac UH-1 in a jungle diorama.

Specifications (UH-1D)

Three-view of UH-1D

General characteristics

• Crew: 1-4
• Capacity: 3,880 lb including 14 troops, or 6 stretchers, or equivalent cargo
• Length: ()
• Wingspan: 48 ft 0 in (14.6 m)
• Height: 14 ft 5 in (4.4 m)
• Empty weight: 5,215 lb (2,365 kg)
• Gross weight: 9,040 lb (4,100 kg)
• Max takeoff weight: 9,500 lb (4,310 kg)
• Powerplant: 1 × Lycoming T53-L-11 turboshaft, 1,100 shp (820 kW)

Performance

• Maximum speed: 135 mph (220 km/h, 117 kn)
• Cruise speed: 125 mph (205 km/h, 109 kn)
• Range: 315 mi (510 km, 274 nmi)
• Service ceiling: (5,910 m)
• Rate of climb: 1,755 ft/min (8.9 m/s)
• Power/mass: 0.15 hp/lb (0.25 kW/kg)

Armament
Variable, but may include a combination of:

• 2x 7.62 mm M60 machine gun, or 2x 7.62 mm GAU-17/A machine gun
• 2x 7-round or 19-round 2.75 in (70 mm) rocket pods
• 2x 7.62 mm Rheinmetall MG3 (German Army and German Luftwaffe)

For information on US armament systems see:

Main article: U.S. Helicopter Armament Subsystems

Popular culture

The image of American troops disembarking from a Huey has become iconic of the Vietnam War, and can be seen in many films, video games and television shows on the subject, as well as more modern settings. The UH-1 is seen in many films about the Vietnam war, including The Green Berets, Platoon, Hamburger Hill, Apocalypse Now, Casualties of War, and Born on the Fourth of July. It is prominently featured in We Were Soldiers as the main helicopter used by the U.S. Cavalry in the Battle of Ia Drang. Author Robert Mason recounts his career as a UH-1 "Slick" pilot in his memoir, Chickenhawk.

See also

• UH-1 Iroquois variants
• Bell Huey - overview of all models
• US Helicopter Armament Subsystems

Related development

• AH-1 Cobra
• AH-1 SuperCobra
• UH-1N Twin Huey
• UH-1Y Venom
• Bell 204/205
• Bell 212
• Bell 214
• Bell 412
• Bell 533
• Panha Shabaviz 2-75

Aircraft of comparable role, configuration, and era

• Sikorsky XH-39

Related lists

• List of active United States military aircraft

References

Bibliography

• Andrade, John M. U.S. Military Aircraft Designations and Serials since 1909. Hersham, Surrey, UK: Midland Counties Publications, 1979. ISBN 0-904597-22-9.
• Chant, Christopher. Fighting Helicopters of the 20th Century (20th Century Military Series). Christchurch, Dorset, UK: Graham Beehag Books, 1996. ISBN 1-85501-808-X.
• Debay, Yves. Combat Helicopters. Paris: Histoire & Collections, 1996. ISBN 2-90818-252-1.
• Drendel, Lou. Huey. Carrollton, Texas: Squadron/Signal Publications, 1983. ISBN 0-89747-145-8.
• Eden, Paul, ed. "Bell UH-1 Iroquois". Encyclopedia of Modern Military Aircraft. Amber Books, 2004. ISBN 1904687849.
• Francillon, René, J. Vietnam: The War in the Air. New York: Arch Cape Press, 1987. ISBN 0-51762-976-3.
• Guilmartin, John Francis and Michael O'Leary. The Illustrated History of the Vietnam War, Volume 11: Helicopters. New York: Bantam Books, 1988. ISBN 0-553-34506-0.
• Mesko, Jim. Airmobile: The Helicopter War in Vietnam. Carrollton, Texas: Squadron/Signal Publications, 1984. ISBN 0-89747-159-8.
• Mikesh, Robert C. Flying Dragons: The South Vietnamese Air Force. London: Osprey Publishing, 1988. ISBN 0-85045-819-6.
• Mutza, Wayne. UH-1 Huey In Action. Carrollton, Texas: Squadron/Signal Publications, 1986. ISBN 0-89747-179-2.
• Mutza, Wayne. "Covertly to Cambodia". Air Enthusiast, Thirty-two, December 1986-April 1987. Bromley, UK:Pilot Press. ISSN 0143-5450. pp. 22-31.
• Mutza, Wayne. UH-1 Huey in Color. Carrollton, Texas: Squadron/Signal Publications, 1992. ISBN 0-89747-279-9.
• Specifications for 204, 205 and 214 Huey Plus
• Weinert, Richard P Jr. History of Army Aviation – 1950-1962. ed. Susan Canedy. Fort Monroe, Virginia: Office of the Command Historian, United States Army Training and Doctrine Command. 1991.
• Bell UH-1 "Huey" on Centennial of Flight.gov.
• Bell UH-1H from the National Air & Space Museum.

External links

• Official Huey II page on BellHelicopter.com
• UH-1N USAF fact sheet
• UH-1D/UH-1H Iroquois utility helicopter and UH-1 Factsheet on Army.mil
• UH-1 history on Navy Air web site
• The Bell UH-1 Huey at Greg Goebel's AIR VECTORS
• Philippine Air Force Huey II Project
• An account of a Medal of Honor rescue flying a Green Hornet
• History of the Huey on timothypruittphoto.com
• The History of Huey The Workhorse Chopper from LiveLeak.com.