In July 1960 a contract was signed for the delivery of 7 helicopters designated as YUH-1D to be subjected to service trials. These helicopters carried the 1,100 hp Lycoming T53-L-11 engine and a larger main rotor, although the main difference was the lengthening of the cabin, which now allowed to carry the two crew members plus 12 or 14 passengers or 6 stretchers and a medical assistant. Passengers could also be replaced by up to 1,800 kg of payload if necessary. On August 16, 1961, their serial production was approved and the first UH-1D entered service in 1963.(Spanish Army’s UH-1H image). The UH-1D was manufactured in light alloy and its fuselage is of the conventional monocoque type and its main rotor was of the semi-rigid type similar to Bell model 204 (UH-1A). Sliding doors with double windows were installed, easily removable if necessary to facilitate access to the cabin. Their 5 fuel tanks have a capacity of 844 liters, of which 799 are usable, leaving the rest as a reserve. Three of them are mounted behind the transmission and the other two under the floor of the cabin. It also had an air heater for the engine, an antifreeze system for the compressor blades and a fire detection system for the engine.(Spanish Army’s UH-1H image). The passenger seats can be configured in different ways or can be easily removed and replaced by 6 stretchers, placed one on top of the other on three supports located next to each side door. The cockpit can be configured for rescue missions with an internal rescue hoist and mounts can be installed to place different light machine guns or a 7.62mm Minigun type. The avionics of origin was relatively simple with communications equipment in the FM, UHF and VHF band, IFF transponder, a Gyromatic Direction Finder compass and a VOR receiver. Some 2,800 units of this variant were produced.(Spanish Army’s UH-1H image). Beginning in 1966, Bell began installing the new 1,400 hp Lycoming T53-L-13 engine in the UH-1D, of which 2,808 units were manufactured. After this modification this variant was re-designated as UH-1H. This variant would become the most manufactured of all the Huey family, reaching 5,435 units built for the US Army. Some units for electronic warfare were built on the basis of the UH-1H, as well as four JUH-1H to evaluate the radar of the SOTAS system. Also 30 HH-1Hs were delivered to the USAF for rescue missions and 10 CUH-1H were delivered for training to the Canadian Air Force that designated them as CH-118.The UH-1H soon had the chance to prove its worth in real operations with the US Army, since they were sent to Vietnam practically as soon as they left the factory. Upon arrival in Vietnam, the Hueys were modified by the units themselves to install different types of weapons, from machine guns to grenade launchers and rocket launchers, since some missions consisted of escorting other Hueys with troops or protecting them during medical evacuations.The Hueys won the affection of the troops, and of the commanders, who had a reliable machine with which they could quickly deploy a good number of soldiers in areas of difficult access. The soldiers immediately gave them nicknames to differentiate them according to the type of weaponry or mission performed. For example the armed Hueys were known as “Hogs” or “Frogs” if they carried rockets, or as “Guns” or “Cobras” if they only carried machine guns. Hueys used only for troop transport were called “Slicks”, and it was common for them to carry a light machine gun on the rear doors for self-protection.The mass arrival of helicopters to the US Army units and having to fight in Vietnam a type of unconventional war, with constant ambushes and guerilla-type engagements, led to the appearance of a new fighting tactic. For the first time they began to talk about the concept “Air Cavalry”, which were basically airborne riflemen. This new doctrine consisted of assigning an air squadron made up of helicopters to each of the Cavalry Divisions. In 1964, this integration was completed, just in time for what was to come.With the creation of the Air Cavalry, missions were assigned to helicopters ranging from the transport of troops or artillery to the installation of supply lines. This ensured that as soon as the soldiers set foot on the ground to attack, they could receive supplies and withdraw the wounded while being supported by fire from the helicopters themselves. In addition, when the operation ended, the helicopters removed them from the area as soon as possible, avoiding counter-attacks from the Vietcong as much as possible.In September 1965, the first air-mobile infantry unit arrived in Vietnam, the 9th Cavalry Regiment, which was integrated into the 1st Air-Mobile Cavalry Division. This Division had about 400 helicopters available, mostly UH-1 accompanied by OH-6A Cayuse and OH-58A Kiowa for observation and CH-47 Chinook for support, which were later joined by AH-1 Cobra attack helicopters.Normally the mission began when an OH-6A Cayuse was sent to assess the area of operations together with a pair of armed helicopters, usually UH-1s in the initial stage. Once the area was chosen, it was attacked by the two armed helicopters before the UH-1 arrived with the infantry. In turn, another infantry unit was embarked in other Hueys ready to support the first unit if it was in a difficult situation against the enemy. The Hueys with the troops flew 450 meters high to avoid fire from the ground. Once in the landing zone, the unit, normally made up of 12 Hueys, took about two minutes to disembark all the soldiers and move away from the area.With the arrival of the AH-1 Cobra attack helicopters, the capacity of the Air Mobile Infantry was improved and units known as “Pink Teams” were implemented. These units consisted of an OH-6A Cayuse observation helicopter and two AH-1 Cobra attack helicopters, which were in charge of “clearing” dangerous landing zones (LZ) for the Hueys. The Cayuses were armed with a 7.62mm machine gun and a 7.62mm Minigun and indicated to the Cobra, which were flying about 500 meters away, the areas to attack with their powerful armament.The armament used in these missions consisted mainly of 7.62mm machine guns, 20mm guns, 40mm grenade launchers and 70mm unguided rockets. In addition, some CH-47 Chinook transport helicopters were prepared as “bombers”. These, fired tear gas or napalm on the blocks and positions of the Vietcong, and also carry powerful weapons onboard, such as a 40mm grenade launcher, a 20mm gun, two 70mm rocket launchers and three 7.62 or 12.7mm machine guns, two behind the cockpit. and one on the rear ramp.Around 7,000 Hueys participated in the Vietnam War, suffering losses of about 3,300, almost 50% of those used, which clearly shows the dangerousness of their missions. Altogether, more than 16,000 Hueys of all variants were manufactured, which makes this helicopter the most successful in history, both in its military and civil variants. Bell signed different licensing agreements to manufacture the UH-1 in different countries such as Germany, Japan, Italy or Taiwan.Of course, the United States has been the largest user of the Huey D and H, with thousands of them distributed among the US Army, USAF, and US Marine Corps. Currently there are no UH-1H in service with US forces since the US Army withdrew them in 2005, although some units of the National Guard kept it until 2016. The USAF maintains about 60 Hueys in service but they are of the UH-1N twin-turbine model, like the Marines, who have another 145, also of the UH-1Y twin-turbine model.(Spanish Army’s UH-1H image). Spain had up to 83 UH-1H in service in the Army (62) and the Air Force (21), which were acquired progressively since 1966. The first six helicopters that arrived for the Army were of a hybrid variant, they were of the UH-1C type with a UH-1F rotor, but they were designated as type UH-1B and were registered with numerals “ET-201 to ET-206”. The rest of the aircraft were of the UH-1H model and were classified in Helicopter Units (UHEL), and later after a reorganization, they passed to the Maneuver Helicopter Battalions (BHELMA) belonging to the Air Force of the Army (FAMET) , carrying out support missions and medium transport.(Spanish Army’s UH-1H image). In December 1971 a dozen of FAMET’s UH-1H were sent to the Spanish territories in the Sahara. Later they would be reinforced with three more Hueys, and they remained there until December 1975, carrying out many missions in a hostile environment. They performed transport, patrol, medevac, liaison, observation and correction of artillery fire missions. On May 13, 1975, two UH-1H that were on patrol were attacked with an SA-7 Grail portable air defense missile, that fortunately missed its target. However, some of the Spanish Hueys suffered damage during its deployment in the Sahara, but none were shot down and the crews were not injured.(Spanish Army’s UH-1H image). The Spanish Army’s UH-1H mounted different weapons during their stay in the Sahara. They used 7.62mm MG-1A1, 12.70mm Browning M2 and 6 barreled 7.62mm XM-93 Minigun machine guns. They also carried 40mm XM-94 grenade launchers and 70mm M-158 and M-200A1 unguided rocket launchers. In the last phase of the conflict, during the so-called Moroccan Green March, which threatened to invade the Sahara, these helicopters carried out surveillance of the territory until it was abandoned by the Spanish Forces on December 19, 1975.(Spanish Army’s UH-1H image). After their service in the Sahara, the FAMET’s Hueys were deployed abroad in international peacekeeping missions, in countries like Kosovo in 2000 or later in Lebannon in 2008. They carried out a last combat mission on July 17, 2002 during the recovery of the Perejil Islet, illegally occupied by Moroccan Military. That morning three armed UH-1H escorted the AS-532 Cougar carrying the Special Operations soldiers who recovered the islet. Fortunately, the operation ended with no casualties on either side, as the Moroccan Marines surrendered without resisting.(Spanish Army’s UH-1H image). With the arrival of Super Puma and Cougar helicopters to the FAMET, the Army’s UH-1H began to be progressively withdrawn, being definitively withdrawn in September 2016. However, a last UH-1H remained in service at the Aviation Academy of the Army until December 12, 2018, when the “H”, as it was nicknamed by the Spanish pilots, stopped flying permanently. In summary, during his 52 years of service they made 231,000 flight hours, suffering the loss of 12 of them in accidents.(Spanish Air Force’s UH-1H image). On the other hand, the Spanish Air Force acquired a batch of 14 AB-205 from the Italian company Agusta, which manufactured them under license and which was the UH-1H variant manufactured by Bell. They were framed in Squadrons 801, 802 and 803 dedicated to SAR (rescue) tasks and with bases in Son Sant Juan (Mallorca), Gando (Gran Canaria) and Cuatro Vientos (Madrid) respectively. These helicopters carried a crane and could fly at night. In 1974 another three UH-1H were purchased from Bell and destined for the Air Force’s Helicopter School located at Cuatro Vientos AFB.(Spanish Air Force’s UH-1H image). In 1975, the Spanish Air Force acquired another 4 UH-1H from the Bell company, three for SAR missions (rescue) and one for special transport (VIP). The School of Helicopters moved in 1980 to the Armilla AFB (Granada), where the helicopters are framed in the 873 Squadron, belonging to the 78th Wing. They served there by conducting instrumental flight courses until 1993, when they were finally retired. The Hueys assigned to SAR (rescue) duties were progressively replaced by the AS-332B Super Puma from 1983 onwards.Dornier manufactured 352 UH-1D for the Luftwaffe and the Heeresfliegertruppen (Army Air Corps) (on the image). In 2019 there were still 29 in service with the Heeresfliegertruppen, although they are progressively being replaced by more modern models. There are still many military forces that keep UH-1 in service, with modern equipment and upgrades, in addition to many higher-performance twin-turbine models. In summary, more than 70 countries have or have had these useful helicopters in service in Land, Sea or Air Forces, apart from civil variants and those used by Police forces around the world.
