Bell UH-1N Twin Huey
The Bell UH-1N Twin Huey is a twin-engine medium military helicopter. A member of the numerous Huey family, it first flew in 1969. The CUH-1N Twin Huey (later CH-135 Twin Huey) was the original version, first ordered by the Canadian Forces.
The UH-1N has a fifteen-seat configuration, with one pilot and fourteen passengers. In cargo configuration it has an internal capacity of 220 ft³ (6.23 m³). An external load of up to 5,000 lb (2,268 kg) can be carried. The UH-1N was later developed into the civil Bell 212.
Based on the stretched fuselage Bell 205, the Bell 212 was originally developed for the Canadian Forces (CF) under the designation CUH-1N Twin Huey. Later the CF adopted a new designation system and the aircraft was re-designated CH-135 Twin Huey. The CF approved the development of the aircraft on 1 May 1968 and purchased 50 aircraft, with deliveries commencing in May 1971.
The US military came very close to not procuring the Twin Huey. The purchase of the aircraft for US military use was opposed by the Chairman of the House Armed Services Committee at the time, L. Mendel Rivers. Rivers took this position because the aircraft powerplant, the Pratt & Whitney Canada PT6T was produced in Canada. The Liberal Canadian government of the time had not supported US involvement in Vietnam and had opposed US policies in southeast Asia, as well as accepting US draft dodgers. Rivers was also concerned that procurement of the engines would result in a trade deficit situation with Canada. Congress only approved the purchase when it was assured that a US source would be found for the PT6T/T400 engines. As a result, the United States military services ordered 294 Bell 212s under the designation UH-1N, with deliveries commencing in 1970.
Unlike in the Canadian Forces, in US service, the UH-1N retained the official name "Iroquois" from the single–engine UH-1 variants, although US service personnel refer to the aircraft as a "Huey" or "Twin Huey".
The UH-1N's main rotor is powered by a PT6T-3/T400 Turbo Twin Pac made up of two Pratt & Whitney Canada PT6 turboshaft engines that drive a single output shaft. They are capable of producing up to 1,342 kW (1,800 shp). Should one engine fail the remaining engine can deliver 671 kW (900 shp) for 30 minutes or 571 kW (765 shp) enabling the UH-1N to maintain cruise performance at maximum weight.
The United States Marine Corps (USMC) modified a large number of their UH-1Ns with a Stability Control Augmentation System (SCAS) which provides servo inputs to the rotor head to help stabilize the aircraft during flight. This modification removed the gyroscopic "Stabilization Bar" on top of the main rotor head, instead relying on the computer system for stability.
From late 1970, the UH-1N re-equipped the USAF 20th Special Operations Squadron in Vietnam, replacing the single-engined UH-1F and UH-1P. Armed with Miniguns (or 40 mm grenade launchers) and rocket pods, and painted camouflage with no US markings and only a Green Hornet insignia, the UH-1N supported Special Forces reconnaissance missions from Cam Ranh Bay.
The United States Air Force employs UH-1Ns to fulfill its ICBM mission, providing a utility helicopter for transport between bases such as Minot AFB, Francis E. Warren AFB and Malmstrom AFB to missile launch sites in North Dakota, Montana, Wyoming, Nebraska, and Colorado. The UH-1N is also used by the 36th Rescue Flight (36 RQF) at Fairchild AFB, WA for conducting Search-and-Rescue (SAR) and medical evacuation missions.
During the 1982 Falklands War, the Argentine Air Force deployed two Bell 212s to Goose Green grass airstrip from where they performed general support duties including the recovery of many downed pilots. By the end of the hostilities both aircraft were still intact but were dismantled by the Argentinians.
USMC UH-1Ns were used by the USMC during its 2003 invasion of Iraq. UH-1Ns provided reconnaissance, and communications support to Marine ground troops. They were also called upon to provide close air support during heavy fighting in Nasiriyah.
As of March 2013, the U.S. Air Force operates 62 UH-1N Hueys: 25 provide security at ICBM sites, 19 are stationed at Joint Base Andrews to evacuate Washington-based government officials in emergencies, and 18 are used for testing and training. Since most were purchased in 1969, the Air Force is seeking replacement of the Huey with the Common Vertical Lift Support Platform (CVLSP). Possible candidates include the UH-72 Lakota, the AW139, and the UH-1Y Venom. The Air Force has been pushing for the CVLSP since 2006 and the program is not currently being funded, although officials are continuing to pursue the effort.
In August 2013, the Air Force said they were close to finalizing a plan to sustain and modernize their UH-1Ns for the next six to ten years. The plan is to sustain the fleet, address flight and safety mandates, investigate modest improvements in capabilities, and reduce capability gaps. While the Huey is one of the oldest platforms in the service, keeping the fleet going is seen as having "minimal risk." Fleet-wide upgrades will include night vision compatible cockpit lighting, crash worthy seats for flight engineers, and installation of a helicopter terrain awareness warning system and traffic collision avoidance device. The Air Force has not decided whether or not to retire the Hueys at the end of the timetable, and is in the process of further acquiring ex-Marine Corps UH-1N models. The Marines are working out a strategy to transfer as many as 26 helicopters to the Air Force, which may add them to their active fleet or keep them in reserve.
The UH-1N has seen combat service in the Colombian armed conflict. On 16 October 2013, an UH-1N helicopter crashed in the northern La Guajira department. The zone of the crash is a hotbed of FARC rebel activity.
The U.S. Marine Corps planned to retire the UH-1N Iroquois by September 2014 after 43 years of service. HMLA-773 (Marine Light Attack Helicopter Squadron 773) was the last Marine squadron operating them, with their last deployment occurring in 2013 where two helicopters sailed on a Royal Netherlands Navy ship for an African Partnership Station deployment. Deliveries began to the Navy and Marine Corps in 1971 totaling 205 UH-1Ns and six VH-1N executive transports for Marine Helicopter Squadron One. The UH-1N was replaced by the upgraded UH-1Y Venom; ten are remanufactured N-model airframes, after which the Marines decided to procure new-built Y-model airframes. Five unarmed HH-1N versions remained in use by the Marines until they were also replaced by UH-1Ys and retired in 2015, the only HH-1Ns remaining from 44 that were converted from 38 UH-1Ns and the six VH-1Ns. The last combat deployment of the UH-1N by the Marines was to Afghanistan in 2010. The Marines retired the UH-1N during a "sundown ceremony" at Naval Air Station Joint Reserve Base New Orleans on 28 August 2014.
- Anti-submarine warfare, anti-shipping version of the AB 212 helicopter, built under license in Italy by Agusta. Operated by the Italian Navy, Hellenic Navy and Islamic Republic of Iran Navy, Peru, Spain, Turkey, and Venezuela.
- The AB 212ASW is a Model 212 Twin Huey with a prominent radome above the cockpit. Early production had a dome-shaped radome, while later production had a flatter "drum" radome. A left side winch is used for dipping the Bendix ASQ-18 sonar. Other changes include structural reinforcement for a gross weight of 11,197 lbs (5080 kg), ECM, shipboard deck tie-down attachments and corrosion protection. Armament is two Mk 44 or Mk 46 torpedoes or two depth charges in the ASW role and four AS.12 air-to-surface wire-guided missiles for the anti-shipping role.
- Argentine Air Force (Bell 212)
- Royal Bahraini Air Force (Bell 212)
- Guatemalan Air Force Fuerza Aérea Guatemalteca (Bell 212)
- Islamic Republic of Iran Air Force
- Islamic Republic of Iran Army (Army Aviation)
- Islamic Republic of Iran Navy (Navy Aviation) (AB 212)
- Turkish Navy (AB 212)
- Army Air Corps (Bell 212)
- Uruguayan Air Force Fuerza Aérea Uruguaya
- Canadian Forces
- 403 Helicopter Operational Training Squadron
- 408 Tactical Helicopter Squadron
- 422 Tactical Helicopter Squadron
- 424 Transport & Rescue Squadron
- 427 Tactical Helicopter Squadron
- 430 Tactical Helicopter Squadron
- 444 Combat Support Squadron
- VU 32 - Navy Utility Squadron
- Aerospace Engineering Test Establishment
- Base Flight Cold Lake
- Base Rescue Goose Bay
Aircraft on display
Specifications (USMC UH-1N, as modified)
- Crew: 4 (pilot, co-pilot, crew chief, gunner)
- Capacity: 6-8 combat-equipped troops, or equivalent cargo
- Length: 57 ft 8 in (12.69 m)
- Rotor diameter: 48 ft 0 in (14.6 m)
- Height: 14 ft 5 in (4.4 m)
- Disc area: 1,808 ft² (168.0 m²)
- Empty weight: 6,100 lb (2,765 kg)
- Useful load: 4,400 lb (1,996 kg)
- Max. takeoff weight: 10,500 lb (4,763 kg)
- Powerplant: 2 × Pratt & Whitney Canada T400-CP-400 turboshaft, 900 shp (671 kW), (total 1,250 shp; 932 kW) each
- Maximum speed: 130 knots (135 mph, 220 km/h)
- Cruise speed: 110 knots (126 mph, 207.3 km/h)
- Range: 248 nmi (286 mi, 460 km)
- Service ceiling: 17,300 ft (5,273 m)
- Rate of climb: 1,755 ft/min (8.9 m/s)
- 2.75-inch (70 mm) rocket pods,
- 0.50 in (12.7 mm) GAU-16 machine gun,
- 7.62 mm (0.308 in) GAU-17 minigun or 7.62 mm (0.308 in) M240 lightweight machine gun
CH-135 Twin Huey 135102 serving with the Multinational Force and Observers Sinai, Egypt, 1989.
CH-135 Twin Huey 135137 in the original blue-gray and green camouflage pattern worn by these aircraft prior to 1986/88.
CH-135 Twin Huey 135127 from Base Rescue Goose Bay in the later SAR scheme used after 1986–88.
CH-135 Twin Huey 135103 in special flight test markings. The aircraft was used by the Aerospace Engineering Test Establishment at CFB Cold Lake, 1987.
CH-135 Twin Huey 135103 after repainting in anti-IR olive and green scheme
Canadian CH-135 Twin Hueys serving with the Multinational Force and Observers Sinai, Egypt 1989