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Bell UH-1 Iroquois

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A military helicopter is a helicopter that is either specifically built or converted for use by military forces . A military helicopter's mission is a function of its design or conversion. The most common use of military helicopters is transport of troops , but transport helicopters can be modified or converted to perform other missions such as combat search and rescue (CSAR), medical evacuation (MEDEVAC), airborne command post, or even armed with weapons for attacking ground targets. Specialized military helicopters are intended to conduct specific missions. Examples of specialized military helicopters are attack helicopters , observation helicopters and anti-submarine warfare (ASW) helicopters.

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126-581: The Bell UH-1 Iroquois (nicknamed " Huey ") is a utility military helicopter designed and produced by the American aerospace company Bell Helicopter . It is the first member of the prolific Huey family , as well as the first turbine-powered helicopter in service with the United States military . Development of the Iroquois started in the early 1950s, a major impetus being a requirement issued by

252-451: A 7-round rocket pod on each side. Aircrew were armed with twin M60 flexible mounts in each door. UH-1 helicopters were used in many roles including troop transport, medevac and Bushranger gunships for armed support. No. 35 Squadron and No. 5 Squadron also operated the Iroquois in various roles through the 1970s and 1980s. Between 1982 and 1986, the squadron contributed aircraft and aircrew to

378-607: A Dakota and act as "beaters" to drive the guerillas into stop groups landed by the helicopters. During the Troubles , the Provisional Irish Republican Army (IRA) became adept at avoiding conventional, fixed roadblocks and patrols. To prevent predictable patterns, the patrols were deployed by helicopter, known as Eagle Patrols, and were then able to disrupt the IRA's ability to move personnel and arms. In

504-569: A French license were not to be exported to other foreign nations without its express approval. Yet another form of common licensing restriction related solely to the licensing activity, regulating whether the specified product was fully produced or partly assembled, and whether entire products or their individual components were manufactured. The governments of Germany and Switzerland imposed similar restrictions on military vehicles manufactured in Argentina and Chile under license. In some cases,

630-873: A Singapore-based logging company but were, instead, delivered in October 1978 to the Royal Rhodesian Air Force to skirt a United Nations -endorsed embargo imposed on the country during the Rhodesian Bush War . In 1960 Subaru made agreement to produce the HU-1B for Japan, which was renamed the UH-1B in 1992, along with the HU-1H, renamed UH-1H. Bell and Suburu developed the UH-1J. Entering service starting in 1993, 130 UH-1J were produced by Fuji for

756-558: A UH-1F on a 26 November 1968 mission that earned him the Medal of Honor . During the course of the conflict, 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 in

882-489: A 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

1008-553: A cost-cutting measure some nations and services have been tempted to use what are essentially commercial helicopters for military purposes. For example, it has been reported that China is carrying out a rapid enlargement of its assault helicopter regiments with the civilian version of the Russian Mil Mi-17 . These helicopters without armour and electronic counter measures will function well enough for training exercises and photo opportunities but would be suicidal to deploy in

1134-761: A lengthened cabin, four-blade rotor, and two more powerful GE T700 engines. The UH-1Y entered service with the USMC in 2008. The Bell 412 is an improved 4-rotor version of the twin-engined Bell 212, and while not adopted by the US, was chosen by Canada ( CH-146 Griffon ), license produced in Italy as the Augusta-Bell AB412, and is going to be made for the Japan Self Defense Force in Japan by Subaru. It

1260-413: A licensee who is authorized to use such rights under certain conditions. The licensee is manufacturing a product for which it has been granted production rights under specific conditions, while the licensor retains ownership of the intellectual property thereof. In some cases the licensor will supply the necessary technical data, prototypes, and/or machine tools to the licensee. While licensed production

1386-639: A medic, two more than the earlier models. 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 enhanced 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 1961. Seven pre-production/prototype aircraft had been delivered for testing at Edwards AFB starting in March 1961. The 205

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1512-567: A medical attendant. Army testing of the UH-1B started in November 1960, with the first production aircraft delivered in March 1961. Bell commenced development of the UH-1C in 1960 in order 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 all weapons systems in use or under development. The Army eventually refitted all UH-1B aircraft with

1638-438: A poor quality licensed product may damage the reputation of the original licensor. However, this is not considered a form of consumer fraud unless the product is unlicensed or counterfeit . Unlicensed production is the utilization of foreign manufacturing technology without a license, achieved through industrial espionage or reverse engineering . Products in high demand on the international market can be reproduced, based on

1764-534: A raid that led to the arrest of an Afghan Border Police commander on corruption charges. Nine Argentine Army Aviation UH-1Hs and two Argentine Air Force Bell 212 were included with the aircraft deployed during the Falklands War . They performed general transport and SAR missions and were based at Port Stanley (BAM Puerto Argentino). Two of the Hueys were destroyed and, after the hostilities had ended,

1890-451: 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

2016-478: 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 on 21 February 1964; a total of 192 Iroquois of this model were completed. Due to production line realities at Bell, the UH-1E was produced in two versions, both with the same UH-1E designation. The first 34 built were essentially UH-1B airframes with

2142-803: A stabilised mount along with multi-function lasers capable of acting as laser rangefinder and targeting designators for weapons systems. By nature of the mission, the observation helicopter's primary weapons are its sensor suite and communications equipment. Early observation helicopters were effective at calling for artillery fire and airstrikes . With modern sensor suites, they are also able to provide terminal guidance to anti-tank guided weapons, laser-guided bombs and other missiles and munitions fired by other armed aircraft. Observation helicopters may also be armed with combinations of gun and rocket pods and sometimes anti-tank guided missiles or air-to-air missiles , but in smaller quantities than larger attack helicopters. Primarily, these weapons were intended for

2268-598: A total of 766 aircraft produced, including five for the Royal Australian Navy and five for Norway. While earlier short-body Hueys were a success, the Army wanted a version that could carry more troops. Bell's solution was to stretch the HU-1B fuselage by 41 in (104 cm) and use the extra space to fit four seats next to the transmission, facing out. Seating capacity increased to 15, including crew. The enlarged cabin could also accommodate six stretchers and

2394-556: A variety of weapons, including rockets, grenade launchers, and machine guns, and were often modified in the field to suit specific operations. The United States Air Force deployed its Iroquois to Vietnam, using them to conduct reconnaissance operations, psychological warfare, and other support roles. Other nations' armed air services, such as the Royal Australian Air Force , also dispatched their own Iroquois to Vietnam. In total, around 7,000 Iroquois were deployed in

2520-454: A weakness. Emplaced insurgents and local sympathisers may observe such facilities covertly and gather intelligence on the schedules and routes of patrols and convoys. With this intelligence the insurgents can time their operations to avoid the COIN forces or plan ambushes to engage them, depending on their own tactical situation. Helicopters return a measure of surprise and tactical flexibility to

2646-541: A wider chord vertical fin on the tail rotor pylon and larger synchronized elevators. Bell also introduced a dual hydraulic control system for redundancy as well as 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 liters ), and gross weight was raised to 9,500 lb (4,309 kg), giving a nominal useful load of 4,673 lb (2,120 kg). UH-1C production started in June 1966 with

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2772-509: Is a development of early Bell model designs, such as the Bell 47 with which it shares common design features, including a damped 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 is also responsible for the characteristic 'Huey thump' sound when the aircraft is in flight, which is particularly evident during descent and in turning flight. The tail rotor

2898-452: Is a multi-purpose helicopter . A utility military helicopter can fill roles such as ground attack , air assault , military logistics , medical evacuation , command and control , and troop transport . While not essential to combat operations, helicopters give a substantial advantage to their operators by being a force multiplier . To maximise their impact, helicopters are utilised in a combined arms approach. High-intensity warfare

3024-563: Is a popular commercial and military helicopter, and it competed in the early 2000s Army Light Utility Helicopter program, but lost to what would be the UH-72 Lakota. That program replaced aging UH-1 and OH-58A/C models being used by the National Guard. The Bell UH-1 Iroquois is a utility helicopter designed for military use. It has a metal fuselage of semi- monocoque construction with tubular landing skids and two rotor blades on

3150-544: Is automatically governed, but are used for starting and shutting down the engine. The cyclic and collective control the main rotor pitch through push-pull tube linkages to the swashplate, 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 push-pull tubes similar to the UH-1N Twin Huey . The HU-1A (later redesignated UH-1A) first entered service with

3276-646: Is characterized by large arrays of conventional armed forces, including mass formations of tanks , with significant air defenses. Helicopter armament and tactics were changed to account for a less-permissive flight environment. Anti-tank missiles , such as the SS.11 and the Aérospatiale SS.12/AS.12 were developed and mounted on French military helicopters. In turn, the United States adapted its BGM-71 TOW for firing from helicopters and eventually developed

3402-526: Is defined as an overseas production arrangement, usually as a direct result of inter-state trade agreements, that permits a foreign government or entity to acquire the technical information to manufacture all or part of an equipment or component patented in the exporting country. According to the World Intellectual Property Organization (WIPO), it must constitute a partnership between an intellectual property owner and

3528-442: 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 synchronized elevator on the tail boom, which is linked to the cyclic control and allows a wider center of gravity range. The standard fuel system consists of five interconnected fuel tanks, three of which are mounted behind

3654-417: Is limited to the installed power and lift capability and the limits installed equipment places on useful payload. The most extensive armour is placed around the pilots, engines, transmission, and fuel tanks. Fuel lines, control cables and power to the tail rotor may also be shrouded by Kevlar armour. The most heavily armoured helicopters are attack, assault and special forces helicopters. In transport helicopters

3780-676: Is made up of two pilot seats and additional 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, with two, two-man bench seats facing outwards from the transmission structure on either side of the aircraft. All passenger seats are constructed of aluminum tube frames with canvas material seats, and are quickly removable and reconfigurable. The cabin may also be configured with up to six stretchers, an internal rescue hoist, auxiliary fuel tanks, spotlights, or many other mission kits. Access to

3906-410: Is often dependent on the appropriate technology transfers , it does not necessarily entail ownership and management of the overseas production by the technology supplier. However, the licensor does retain the right to continue to use the licensed property, and to attribute further licenses to third parties. Occasionally, licensees may themselves sub-license a third party with or without the agreement of

Bell UH-1 Iroquois - Misplaced Pages Continue

4032-534: Is that personnel and cargo can be moved to and from locations without requiring a runway for takeoffs and landings. Cargo is carried either internally, or externally by slung load where the load is suspended from an attachment point underneath the aircraft. Personnel are primarily loaded and unloaded while the helicopter is on the ground. However, when the terrain restricts even helicopters from landing, personnel may also be picked up and dropped off using specialized devices, such as rescue hoists or special rope lines, while

4158-543: 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

4284-624: The AGM-114 Hellfire . Meanwhile, the Soviet Union adapted the 3M11 Falanga missile for firing from the Mil Mi-24 . In the air, attack helicopters armed with anti-tank missiles, and one or more unarmed, or lightly armed scout helicopters operate in concert. The scout helicopter, flying at low level in a nap-of-the-earth approach, attempts to both locate the enemy armoured columns and to map out approaches and ambush positions for

4410-679: The Combat search and rescue (CSAR) mission. Some services use a version of their operational helicopters, usually in the light class, for pilot training. For example, the British have used the Aérospatiale Gazelle both in operations and as a trainer. Some services also have an ab initio phase in training that uses very basic helicopters. The Mexican Navy has acquired a number of the commercially available Robinson R22 and R44 helicopters for this purpose. A utility helicopter

4536-845: The Experimental Military Unit during the Vietnam War. Numerous UH-1s were operated by the Salvadoran Air Force ; during the 1980s, it became the biggest and most experienced combat helicopter force in Central and South America, fighting for over a decade during the Salvadoran Civil War and having been trained by US Army in tactics developed during the Vietnam War. By the start of 1985, El Salvador had 33 UH-1s in its inventory, some configured as gunships and others as transports; furthermore, in

4662-665: The Gulf War in 1991. In the latter conflict, in excess of 400 Iroquois performed a variety of missions in the region; over a nine-month period, the fleet cumulatively reached 31,000 flight hours and achieved a stable fully mission capable rate of 70%. The type comprised more than 20% of all rotorcraft across the coalition and recorded 21% of the overall flying hours. Even after the Gulf War, the US Army had more than 2,800 Iroquois in its inventory; in particular, 389 UH-1Vs comprised 76% of

4788-697: The Mil Mi-28 N, the Kamov Ka-52 , and the AH-64D Longbow , incorporate sensors and command and control systems to relieve the requirement for scout helicopters. To enhance the combat endurance of these missile-armed helicopters, transport helicopters were used to carry technicians, reloads and fuel to forward locations. Establishing these forward arming and refuel points (FARP) at pre-arranged locations and times allowed armed or attack helicopters to re-arm and refuel, often with their engines running and

4914-797: The UH-1H . In 1962, the United States Marine Corps 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,

5040-510: The United Nations Office on Drugs and Crime has noted that while licensing companies often provide quality control measures, and there is some incentive for licensees to comply or risk legal action and the ensuing damage to their own profit, manufacturers who engage in unlicensed production are under no such obligations. Another method of circumventing the need for a license involves a manufacturer making slight modifications in

5166-682: The United States Air Force (USAF) 20th Helicopter Squadron was formed at Tan Son Nhut Air Base in South Vietnam, equipped initially with CH-3C helicopters. By June 1967, the UH-1F and UH-1P were also added to the unit's inventory and, by the end of the year, the entire unit had shifted from Tan Son Nhut to Nakhon Phanom Royal Thai Air Force Base , with the CH-3s transferring to the 21st Helicopter Squadron . On 1 August 1968,

Bell UH-1 Iroquois - Misplaced Pages Continue

5292-551: The United States Army for a new medical evacuation and utility helicopter . The Bell 204 , first flown on 20 October 1956, was warmly received, particularly for the performance of its single turboshaft engine over piston engine -powered counterparts. An initial production contract for 100 HU-1A s was issued in March 1960. In response to criticisms over the rotorcraft's power, Bell quickly developed multiple models furnished with more powerful engines; in comparison to

5418-563: The aftermath of the American invasion of Iraq helicopters have been used as aerial supply trucks and troop transports to prevent exposure to ambushes set by the Iraqi insurgency . Due to the cost and complexity of training and support requirements, insurgent forces rarely have access to helicopters. The major Western European helicopter manufacturers are Leonardo S.p.A. (formerly AgustaWestland ) and Eurocopter Group . In North America,

5544-611: The licensed production of those companies products, whilst building up their own ability to design and manufacture helicopters through a process of workshare and technology transfer. In India, Hindustan Aeronautics Limited is the main helicopter manufacturer for the Indian Armed Forces . In the Soviet planned economic system, the Mil and Kamov OKBs were responsible only for the design of helicopters. A re-organisation of

5670-541: The "Blue Hawks", was established at Naval Air Station Point Mugu , California on 11 June 1977 and its sister squadron, Helicopter Attack Squadron (Light) Four (HA(L)-4), known as the Red Wolves , was formed at Naval Air Station Norfolk, Virginia on 1 July 1976. The last regular Navy Huey's, HH-1's for search and rescue were retired in 2009 and replaced by H-60 Seahawks, and the last Marine Corp UH-1N were retired in 2014. The UH-1H has been used on multiple occasions by

5796-627: The 1960s, the development of the turboshaft engine and transistor technology changed the face of maritime helicopter aviation. The turboshaft engine allowed smaller helicopters, such as the Westland Wasp , to operate from smaller vessels than their reciprocating engine predecessors. The introduction of transistors allowed helicopters, such as the Sikorsky SH-3 Sea King , to be equipped with integral dunking sonar , radar and magnetic anomaly detection equipment. The result

5922-462: The 1970s. The Seawolves worked as a team with Navy river patrol operations. Four years after the disestablishment of HA(L)-3 , the Navy determined that it still had a need for gunships, establishing two new Naval Reserve Helicopter Attack (Light) Squadrons as part of the newly formed Commander, Helicopter Wing Reserve (COMHELWINGRES) in 1976. Helicopter Attack Squadron (Light) Five (HA(L)-5) , nicknamed

6048-591: The 204B with the T58 engine. Because the T58 output shaft is at the rear, and was thus mounted in front of the transmission on the HH-3, it had to have a separate offset gearbox (SDG or speed decreaser gearbox) at the rear, and shafting to couple to the UH-1 transmission. The single-engine UH-1 variants were followed by the twin-engine UH-1N Twin Huey ( Bell 212 ) and years later the UH-1Y Venom . Bell began development of

6174-527: 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 . During 1966, Bell installed the 1,400 shp (1,000 kW) Lycoming T53-L-13 engine to provide more power for the helicopter. The pitot tube was relocated from the nose to the roof of the cockpit to prevent damage during landing. Production models in this configuration were designated as

6300-899: The American Drug Enforcement Administration (DEA); initially, these were usually borrowed from the U.S. Army to support planned missions, such for Operation Snowcap , a large multi-year counter- narcotics action covering nine countries across Latin America . During the War in Afghanistan , the DEA made use of a number of UH-1s stationed in the country for the purpose of conducting counter-narcotics raids. Operated by contractors, these Hueys provide transportation, surveillance, and air support for DEA FAST teams. During July 2009, four UH-1Hs and two Mi-17s were used in

6426-689: The Army's medevac aircraft. Nevertheless, plans were mooted as early as 1992 to undertake a slow withdrawal of the aging type in favor of larger and more technologically advanced rotorcraft. The US Army began phasing out the UH-1 with the introduction of the Sikorsky UH-60 Black Hawk starting in the 1980s, although the Army UH-1 Residual Fleet had around 700 UH-1s that were to be retained until 2015, primarily in support of Army Aviation training at Fort Rucker and in selected Army National Guard units. Army support for

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6552-789: The Australian helicopter detachment which formed part of the Multinational Force and Observers peacekeeping force in the Sinai Peninsula , Egypt . During 1988, the RAAF began to re-equip with S-70A Blackhawks . In 1989 and 1990, the RAAF's UH-1H Iroquois were subsequently transferred to the 171st Aviation Squadron in Darwin, Northern Territory and the 5th Aviation Regiment based in Townsville, Queensland following

6678-465: The Bell 412, entered service in Canada but not the US. A further updated UH-1 with twin engines and four-bladed derivative, the Bell UH-1Y Venom , was also developed during the early twenty-first century for the USMC. In US Army service, the Iroquois was gradually phased out following the introduction of the Sikorsky UH-60 Black Hawk and the Eurocopter UH-72 Lakota in the early 21st century. However, hundreds were still in use more than 50 years following

6804-432: The British, Spanish, and Italian navies, the larger helicopters form the main anti-submarine strength of carrier air wings. When operating from shore bases, the helicopters are used as anti-submarine pickets to protect against hostile submarines loitering outside military ports and harbours; their endurance and payload providing advantages over smaller helicopters. Soviet maritime helicopters, operating from its cruisers, had

6930-581: The COIN commander. Patrols need not start and end in the same place (the main entrance of the local compound), nor do supply convoys need follow the same roads and highways. During the Rhodesian Bush War , the Rhodesian military developed and refined " Fireforce " tactics, using small flights of light helicopters, the helicopters would be equipped as gunships to directly attack insurgents with aerial gunfire and also as either an airborne command/observation post or troop transport. Once contact had been established against enemy guerillas paratroopers would be dropped by

7056-413: The Huey in State National Guard took place. The Washington, D.C. Army National Guard had its last flight in 2011, and Pennsylvania in 2010. The final U.S. Army UH-1 was retired in late 2016, and transferred to a State police department. In context, the Huey is still in service with Armed Forces overall, and the Air Force UH-1N were still in service as of 2024, but scheduled for replacement. In October 1965,

7182-400: The Iroquois were produced. A dedicated attack helicopter , the Bell AH-1 Cobra , was derived from the UH-1, and retained a high degree of commonality. The Bell 204 and 205 are Iroquois versions developed for the civilian market. In response to demands from some customers, a twin-engined model, the UH-1N Twin Huey , was also developed during the late 1960s; a further updated four rotor model,

7308-476: The Japanese Self-Defense Force. Military helicopter Military helicopters play an integral part in the sea, land and air operations of modern militaries. Generally manufacturers will develop airframes in different weight/size classes which can be adapted to different roles through the installation of mission specific equipment. To minimise development costs the basic airframes can be stretched and shortened, be updated with new engines and electronics and have

7434-436: The LZ. The advantage of air assault over an airborne assault is the ability of the helicopters to continually resupply the force during the operation, as well as to transport the personnel and equipment to their previous location, or a follow-on location if the mission dictates. The first reconnaissance and observation aircraft were balloons, followed by light airplanes, such as the Taylorcraft L-2 and Fieseler Fi 156 . As

7560-412: The Lycoming T53-L-11 engine producing 1,100 shp (820 kW). When Bell switched production to the UH-1C, the UH-1E production benefited 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. The United States Air Force (USAF) held

7686-464: The M60 machine gun. AS-10 and SS-11 missiles were tested in several different configurations. High-capacity rocket launchers were also tested, such as the XM3 launcher, which had 24 launching tubes. Press photos were taken with the XM5 and XM3 installed on the same aircraft, but this arrangement could not be used because it was more than the gross take-off weight of the aircraft. During the Easter Offensive of 1972 by North Vietnam, experimental models of

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7812-437: The TOW-firing XM26 were taken out of storage and sent to South Vietnam in response to the onslaught. The pilots had never fired a TOW missile before, and were given brief crash courses. Despite having little training with the units, the pilots managed to hit targets with 151 of the 162 missiles fired in combat, including a pair of tanks. The airborne TOW launchers were known as "Hawks Claws" and were based at Camp Holloway . During

7938-413: The U.S. 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 too complex to maintain easily. During November 1953, revised military requirements were submitted to the Department of the Army. Twenty companies submitted designs in their bid for

8064-714: The UH-1D and flew operationally from 1963. During its Vietnam War service, the UH-1 was used for various purposes and various terms for each task abounded. UH-1s tasked with ground attack or armed escort were outfitted with rocket launchers, grenade launchers, and machine guns. As early as 1962, UH-1s were modified locally by the companies themselves, who fabricated their own mounting systems. 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

8190-459: The UH-1N for Canada in 1968. It changed to the more powerful Pratt & Whitney Canada PT6T twin-engine set. The US also ordered the helicopter with the USAF receiving it in 1970. Canada's military, the U.S. Marine Corps, and the U.S. Navy first received the model in 1971. In 1996, the USMC launched the H-1 upgrade program via the award of a contract to Bell Helicopter for development of the improved UH-1Y and AH-1Zs variants. The UH-1Y includes

8316-526: The USAF announced that the Boeing/Leonardo MH-139 (an AW-139 variant) had won a competition to replace the UH-1N fleet. The UH-1N fleet is in service as of 2024, as production of the new type is ramped up. The US Navy acquired a number of surplus UH-1B helicopters from the U.S. Army, these rotorcraft were modified into gunships, outfitted with special gun mounts and radar altimeters. They were known as Seawolves in service with Navy Helicopter Attack (Light) (HA(L)-3). UH-1C helicopters were also acquired during

8442-414: The United States to rescue downed aircrews and injured personnel in remote areas of the China Burma India Theater , from April 1944 until the war's end. The use of helicopters for rescue during combat increased during the Korean War and the Algerian War . In the Vietnam War the USAF acquired Sikorsky S-61R (Jolly Green Giant) and Sikorsky CH-53 Sea Stallion (Super Jolly Green Giant) helicopters for

8568-449: The Vietnam theatre, over 3,300 of which were believed to be destroyed. Various other conflicts have seen combat deployments of the Iroquois, such as the Rhodesian Bush War , Falklands War , War in Afghanistan , and the 2007 Lebanon conflict . The Iroquois was originally designated HU-1 , hence the Huey nickname, which has remained in common use, despite the official redesignation to UH-1 in 1962. Various derivatives and developments of

8694-612: The West German Bundeswehr . These saw service with both the German Army and German Air Force as utility helicopters, they were also commonly used for search and rescue (SAR) missions. After being replaced by newer twin-engine Eurocopter EC145s , the last UH-1Ds in German service were withdrawn on 12 April 2021. Israel withdrew its UH-1s from service in 2002, after 33 years of operation. They were replaced by Sikorsky UH-60 Blackhawk helicopters with an initial batch of 10 delivered during 1994. While some were passed on to pro-Israeli militias in Lebanon, eleven other UH-1Ds were reportedly sold to

8820-557: The additional role of guidance of the cruisers' long range anti-shipping missiles. Maritime helicopters are navalised aircraft for operation from ships. This includes enhanced protection against salt water corrosion , protection against ingestion of water, and provision for forced ditching at sea. As helicopters came into military service, they were quickly pressed into service for search and rescue and medical evacuation . During World War II, Flettner Fl 282s were used in Germany for reconnaissance , and Sikorsky R-4s were used by

8946-462: The aircraft hovers overhead. Air assault is a military strategy that relies heavily on the use of transport helicopters. An air assault involves a customized assault force that is assembled on the pick-up zone and staged for sequential transport to a landing zone (LZ). The idea is to use the helicopters to transport and land a large number of troops and equipment in a relatively short amount of time, in order to assault and overwhelm an objective near

9072-456: The assault role in actual combat situations. The intention of China appears to be to retrofit these helicopters with locally produced electronics and armour when possible, freeing available funds to allow rapid creation of enough regiments to equip each of its Group Armies , allowing a widespread buildup of experience in helicopter operations. Attack helicopters are helicopters used in the anti-tank and close air support roles. The first of

9198-427: The attack helicopters. Late-model scout helicopters include laser designators to guide missiles fired from the attack helicopters. After finding a target, the scout helicopter can locate it and then direct the attack helicopter's missile where to fire. The attack helicopters have only to rise from cover briefly to fire their missiles before returning to a concealed location. Late-development of attack helicopters, such as

9324-482: 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. 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

9450-477: The capability of the early helicopters was as plane guard - tasked with the recovery of pilots who had ditched near an aircraft carrier . As helicopter technology matured with increased payload and endurance , anti-submarine warfare (ASW) was added to the helicopter's repertoire. Initially, helicopters operated as weapons delivery systems, attacking with air-launched torpedoes and depth charges based on information provided by its parent and other warships. In

9576-473: The cargo hook on the bottom and is located at the aircraft's center of gravity. The lift beams were changed to steel later in the UH-1H's life, due to cracking on high-time airframes. The semi-monocoque 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, and the 42-degree and 90-degree gearboxes of

9702-521: The conflict, 7,013 UH-1s served in Vietnam and of these 3,305 were destroyed. In total, 1,151 pilots were killed, along with 1,231 other crew members (these figures are not including Army of the Republic of Vietnam losses). Post Vietnam, the US Army continued to operate large numbers of Iroquois; they would see further combat during the US invasion of Grenada in 1983, the US invasion of Panama in 1989, and

9828-645: 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 with the designation XH-40 . 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 Fort Worth , Texas , with Bell's chief test pilot, Floyd Carlson, at

9954-580: The controls. Even prior to the first flight, the Army had placed an order for six YH-40 service test helicopters. During 1957, a further two prototypes were completed. In 1959, the Army awarded Bell a production contract for 182 aircraft, which was designated "HU-1A" and officially named Iroquois after the Native American nations . The helicopter quickly developed a nickname derived from its HU-1 designation, which came to be pronounced as "Huey". The reference became so popular that Bell began casting

10080-514: The counter-reconnaissance fight—to eliminate an enemy's reconnaissance assets—but they can also be used to provide limited direct fire support or close air support. Among the first practical uses of helicopters when the Sikorsky R-4 and R-5 became available to British and American forces was deployment from navy cruisers and battleships, at first supplementing and later replacing catapult-launched observation aircraft . Another niche within

10206-581: The craft was intended to end in 2004; The UH-1 was retired from active Army service in early 2005. During 2009, Army National Guard retirements of the UH-1 accelerated with the introduction of the Eurocopter UH-72 Lakota . In 2009 the Army National Guard marked 50 years of service of the Huey in the Army, and 40 with the National Guard and had a ceremonial end to its service at that time; in the coming years many final flights of

10332-461: The crew compartment may or may not be fully armoured, a compromise being to give the passengers Kevlar lined seats but to leave the compartment for the most part unarmoured. Survivability is enhanced by redundancy and the placement of components to protect each other. For example, the Blackhawk family of helicopters uses two engines and can continue to fly on only one (under certain conditions),

10458-663: The decision that all battlefield helicopters would be operated by the Australian Army. On 21 September 2007, the Australian Army retired the last of their Bell UH-1s. The last flight occurred in Brisbane on that day with the aircraft replaced by MRH-90 medium helicopters and Tiger armed reconnaissance helicopters. The Royal Australian Navy 's 723 Squadron also operated seven UH-1B from 1964 to 1989, with three of these aircraft lost in accidents during that time. 723 Squadron deployed Iroquois aircraft and personnel as part of

10584-422: The domestic manufacture of preexisting overseas designs. This allowed for a much higher rate of production, and was considerably cheaper than national sourcing and off-the-shelf acquisition. European automobile manufacturers were the first to adopt this practice, producing a number of specialized American components for their passenger cars under license. The United States not only supplied European factories with

10710-499: The door of a UH-1. It was capable of firing 2400 rounds per minute, or about 40 rounds per second. Despite this being a significant reduction from the nearly 100 rounds per second fired by a standard Vulcan cannon, the installation proved too kinetic for the UH-1. Podded versions of the M24 20 mm cannon were tested in combat over Vietnam. There was a wide variety of 7.62 mm automatic weapons tested, including different installations of

10836-479: The early years of the Vietnam War. UH-1B/C gunships were replaced by the new AH-1 Cobra attack helicopter from 1967 to late 1968. The increasing intensity and sophistication of NVA anti-aircraft defenses made continued use of UH-1 gunships 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

10962-403: The economic life of the product. Developing nations began accounting for a significant percentage of licensed production during the late twentieth century. Governments of developing nations often sought to encourage rapid industrialization, reduce dependence on foreign imports, and combat high levels of unemployment by creating and retaining local jobs. However, in many of these nations there

11088-946: The engines are separated by the transmission and placed so that if attacked from any one flank, the engine on that flank acts to protect the transmission and the engine on the other side from damage. Aviation electronics, or avionics , such as communication radios and navigation aids are common on most military helicopters. Specialized avionics, such as electronic countermeasures and identification friend or foe systems, are military specific systems that can also be installed on military helicopters. Other payload or mission systems are installed either permanently or temporarily, based on specific mission requirements; optical and IR cameras for scout helicopters, dunking sonar and search radar for anti-submarine helicopters, extra radio transceivers and computers for helicopters used as airborne command posts . Armour, fire suppression, dynamic and electronics systems enhancements are invisible to casual inspection; as

11214-775: The entire mechanical and flight systems mated to new fuselages to create new aircraft. For example, the Bell UH-1 Iroquois (known as the "Huey") has given rise to a number of derivatives through stretching and re-engining, including the Bell AH-1 . Modern helicopters have introduced modular systems which allow the same airframe to be configured for different roles, for example the Augusta Westland AW101 "Merlin" in Royal Navy service can be rapidly configured for ASW or transport missions in hours. To at

11340-402: The explicit licensing of technological information. Knock-down kits are regarded as a prerequisite to licensed production; they consist of products assembled locally from imported, pre-manufactured parts. Some licensors find it difficult to regulate the quality of their products manufactured under license. It is not always made clear to consumers where exactly a particular good originated, and

11466-504: The first military helicopters became available, their ability to both maneuver and to remain in one location made them ideal for reconnaissance. Initially observation helicopters were limited to visual observation by the aircrew, and most helicopters featured rounded, well-glazed cockpits for maximum visibility. Over time, the human eye became supplemented by optical sensor systems. Today, these include low light level television and forward looking infrared cameras. Often, these are mounted in

11592-514: The following years, the country expanded its UH-1 fleet further with assistance from the US government. Several Salvadorean UH-1M and UH-1H helicopters used were modified to carry bombs instead of rocket pods. The UH-1s enabled the military to avoid ground routes vulnerable to guerilla ambushes; the gunships were typically used to suppress hostile forces ahead of troops being inserted by UH-1 transports. The German aerospace company Dornier constructed 352 UH-1Ds under license between 1967 and 1981 for

11718-540: The helicopter industry in Russia created Russian Helicopters , a holding company to bring together Mil, Kamov, and other helicopter manufacturing and maintenance plants. Licensed production Licensed production is the production under license of technology developed elsewhere. The licensee provides the licensor of a specific product with legal production rights, technical information, process technology, and any other proprietary components that cannot be sourced by

11844-443: The intellectual property owner. Licensing agreements determine the form and scope of compensation to the intellectual property owner, which usually takes the form of a flat licensing fee or a running royalty payment derived from a share of the licensee's revenue. The licenses can be terminated by the licensor, or may expire after a set date; however, the technology and knowledge, once transferred, cannot be rescinded, so even if

11970-491: The licensee. The United States began inserting pro forma statements into licensing agreements known as "side letters" , which required the free sharing of any improvements made to American technology. Other attempts were also made to control the destination of licensed products, particularly with regards to the arms industry . For instance, France stipulated that military vehicles manufactured in South Africa under

12096-449: The licensing agreement expires they remain in the licensee's possession. Two related commercial practices are foreign subcontractor production and the proliferation of knock-down kits . Foreign subcontracting occurs when a product's original manufacturer contracts the production of its individual parts and components to a second party overseas. Such arrangements are not considered examples of licensed production because they do not involve

12222-580: The licensor. This is an especially prominent commercial practice in developing nations , which often approach licensed production as a starting point for indigenous industrial development. While licensed production in developing nations provides stimulus to the production and technical capabilities of local industry, in many cases it remains at least partly dependent on foreign support. The four most common applications of licensed production have historically been automotive engines and parts, weaponry, aircraft, and pharmaceuticals. During World War I , it

12348-455: The main rotor. Early UH-1 models featured a single Lycoming T53 turboshaft engine in versions with power ratings from 700 to 1,400 shp (522 to 1,040 kW). Later UH-1 and related models often featured twin engines and four-blade rotors. All members of the UH-1 family have similar construction. The UH-1H is the most-produced version, and is representative of all types. The main structure consists of two longitudinal main beams that run under

12474-451: The maximum size of the helicopters and the minimum size of the ships. Increasing miniaturisation of electronics, better engines and modern weapons now allow even the modern, destroyer-based, multi-role helicopter to operate nearly autonomously in the ASW, anti-shipping, transport, SAR and reconnaissance roles. Medium- and large-sized helicopters are operated from carriers and land bases. In

12600-720: The modern attack helicopters was the Vietnam era Bell AH-1 Cobra , which pioneered the now classic format of pilot and weapons officer seated in tandem in a narrow fuselage, chin mounted guns, and rockets and missiles mounted on stub wings. To enable them to find and identify their targets, some modern attack helicopters are equipped with very capable sensors such as a millimeter wave radar system. Transport helicopters are used for transporting personnel (troops) and cargo in support of military operations. In larger militaries, these helicopters are often purpose-built for military operations, but commercially available aircraft are also used. The benefit of using helicopters for these operations

12726-409: The name on the helicopter's anti-torque pedals. The official U.S. Army name was almost never used in practice. Even after September 1962, at which point the designation for all models was changed to UH-1 under a unified Department of Defense (DOD) designation system, yet the nickname persisted. While glowing in praise for the helicopter's advances over piston-engined helicopters, the Army reports from

12852-676: The necessary blueprints and licenses, but also sourced American-made tooling equipment accordingly, which allowed the automobile companies to optimize their production lines. By the 1960s it was not uncommon for an entire specialized industry—such as the manufacture of rotary aircraft in the United Kingdom —to be dependent wholly on foreign-licensed components. A number of countries began making improvements to foreign products manufactured under license, and were even able to re-export them successfully. This trend resulted in some technology suppliers imposing additional conditions on

12978-506: 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. In air cavalry troops (i.e., companies ) UH-1s were combined with infantry scouts , OH-6 and OH-58 aero-scout helicopters, and AH-1 attack helicopters to form several color-coded teams (viz., blue, white, red, purple, and pink) to perform various reconnaissance , security, and economy of force missions in fulfilling

13104-479: The original technology supplier did not need to manufacture the product itself—it merely patented a specific design, then sold the actual production rights to multiple clients. This resulted in different companies separately manufacturing identical products licensed from the same licensee. For many licensee companies, licensed production by other firms provides a continuous outlet for their proprietary technology, increasing their return on investment and prolonging

13230-400: 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, 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

13356-469: The prototype's Lycoming YT53-L-1 (LTC1B-1) engine, producing 700 shp (520 kW), by 1966, the Lycoming T53-L-13 , capable of 1,400 shp (1,000 kW), was being installed on some models. A stretched version of the Iroquois, first flown during August 1961, was also produced in response to Army demands for a version that could accommodate more troops. Further modifications would include

13482-621: The remainder were captured by the British military. Three captured aircraft survive as museum pieces in England and Falklands. The Royal Australian Air Force employed the UH-1H until 1989. Iroquois helicopters of No. 9 Squadron RAAF were deployed to South Vietnam in mid 1966 in support of the 1st Australian Task Force . In this role they were armed with single M60 doorguns. In 1969 four of No. 9 Squadron's helicopters were converted to gunships (known as 'Bushrangers'), armed with two fixed forward firing M134 7.62 mm minigun (one each side) and

13608-614: The risks inherent in the development of new products by taking advantage of the proven reputation of products which had already achieved success in foreign markets. The economic life of many products, namely in the automotive and defense sectors, have been prolonged by overseas licensed production long after they were considered obsolete in their countries of origin. Developing nations such as Pakistan and Singapore which built important segments of their industry on licensed production have now themselves become licensors of technology and products to less developed states. Licensed production

13734-431: The rotors still turning, and to quickly return to the front lines. In counter-insurgency (COIN) warfare, the government force establishes its presence in permanent or temporary military bases from which to mount patrols and convoys. The government forces seek to deter the insurgent forces from operating, and to capture or kill those that do. The operation of forces from fixed bases linked by a fixed network of roads becomes

13860-402: The same engine. A new rotor system was developed for the UH-1C to allow higher air speeds and reduce the incidence of retreating blade stall during diving engagements. The improved rotor resulted in better maneuverability and a slight speed increase. The increased power and a larger diameter rotor required Bell's engineers to design a new tail boom for the UH-1C. The longer tail boom incorporated

13986-448: The same or similar design, and branded in ways to make them indistinguishable from the original. When copied and reproduced without a license, certain items are sometimes recopied in a similar manner by a third party. The manufacturers responsible may also grant legitimately registered sub-licenses for their unlicensed products, profiting at the expense of the real intellectual property owner. The quality of unlicensed goods varies greatly;

14112-550: The same time retain flexibility and limit costs, it is possible to fit an airframe for but not with a system, for example in the US Army's Boeing AH-64D Apache variants are all fitted to be able to take the Longbow radar system, but not enough sets have been bought to equip the whole force. The systems can be fitted to only those airframes that need it, or when finances allow the purchase of enough units. Most military helicopters are armoured to some extent; however, all equipment

14238-601: The service tests of the YH-40 found it to be underpowered with the production T53-L-1A powerplant producing a maximum continuous 770 shaft horsepower (570 kilowatts ). The Army indicated the need for improved follow-on models even as the first UH-1As were being delivered. In response, Bell proposed the UH-1B, equipped with the Lycoming T53-L-5 engine producing 960 shp (720 kW) and a longer cabin that could accommodate either seven passengers or four stretchers and

14364-626: The so-called Secret War . USAF UH-1s were often equipped with automatic grenade launchers in place of the door guns. The XM-94 grenade launcher had been tested on Army rotorcraft prior to its use by the USAF. The unit was capable of firing 400 grenades per minute, up to 1,500 yards effective range. Into the twenty-first century, the USAF operates the UH-1N for support of intercontinental ballistic missile (ICBM) sites, including transport of security personnel and distinguished visitors. On 24 September 2018,

14490-504: The tail rotor. The main rotor transmission consists of a 90 degree bevel gear assembly with a reduction ratio of 2.14:1, followed by a 2-stage planetary gearset with a ratio of 9.53:1 (two stages of 3.087:1 each). This is in addition to the output gearbox of the T53 engine with a reduction ratio of 3.19:1. This combined reduction results in 324 rpm at the main rotor. The two-bladed, semi-rigid rotor design, with pre-coned and underslung blades,

14616-491: The three primary manufacturers are Boeing ( Boeing Vertol and McDonnell Douglas ), Bell Helicopter and Sikorsky Aircraft . In Japan, the three main manufacturers of helicopters are the aviation arms of the Japanese conglomerates Mitsubishi , Kawasaki and Fuji Heavy Industries . These companies initially followed a business model based on forming strategic partnerships with foreign, usually American, companies with

14742-435: The traditional cavalry battlefield role. The Army tested a great variety of experimental weapons on the UH-1; nearly anything that could be carried. The Army desired weapons with large calibers and high rates of fire, which led to the testing of a 20 mm cannon on a large mount bolted to the cabin floor. The size of the weapon allowed very little room for movement. The Army further tested a full-size Vulcan cannon firing out

14868-436: 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. While the five main fuel tanks are self-sealing , the UH-1H was not equipped with factory armor, although armored pilot seats were available. Internal seating

14994-641: The troop transport and medevac roles. UH-1s also flew hunter-killer teams with observation helicopters, namely the Bell OH-58A Kiowa and the Hughes OH-6 Cayuse ( Loach ). Towards the end of the conflict, 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 . USAF Lieutenant James P. Fleming piloted

15120-664: The type's introduction. In excess of 16,000 Iroquois have been built since 1960. With new orders from Japan and the Czech Republic, the UH-1 remains in production. Several export customers, such as Canada, Germany, Taiwan, Japan, and Italy, opted to produced the type under license . Operators have been located across the world, including the Americas, Europe, Asia, Africa, the Middle East, and the Pacific region. In 1952,

15246-593: The unit was redesignated the 20th Special Operations Squadron. The 20th SOS's UH-1s were known as the Green Hornets , stemming from their color, a primarily green two-tone camouflage (green and tan) was carried, and radio call-sign "Hornet". The main role of these helicopters were to insert and extract reconnaissance teams, provide cover for such operations, conduct psychological warfare, and other support roles for covert operations especially in Laos and Cambodia during

15372-515: The use of all-aluminum construction, the adoption of a rotor brake, and alternative powerplants. The Iroquois was first used in combat operations during the Vietnam War , the first examples being deployed in March 1962. It was used for various purposes, including conducting general support, air assault , cargo transport, aeromedical evacuation , search and rescue , electronic warfare, and ground attack missions. Armed Iroquois gunships carried

15498-543: Was an aircraft able to more quickly respond to submarine threats to the fleet without waiting for directions from fleet vessels. Today, maritime helicopters such as the Sikorksy SH-60 Seahawk and the Westland Lynx are designed to be operated from frigates , destroyers and similar size vessels. The desire to carry and operate two helicopters from frigate- and destroyer-sized vessels has affected

15624-423: Was initially equipped with a 44-foot (13 m) main rotor and a Lycoming T53-L-9 engine with 1,100 shp (820 kW). The rotor was lengthened to 48 feet (15 m) with a chord of 21 in (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 lb (4,309 kg). The Army ordered production of

15750-564: Was more common for licensing agreements to take place between companies in the same country; for example, Opel was granted a license to produce BMW -designed aircraft engines for the German war effort. During the 1920s, European economists began advocating licensed production of foreign goods as the cure for "industrial particularism" —it allowed countries to bypass the costly research and development stage of acquiring products with which their own industries were unfamiliar, and refocus on

15876-492: Was not a strong tradition of technology-based industrial development, and local firms were seldom active participants in creating indigenous technology through research and development. Since their research capacity was typically too limited to meet their goals, adopting licensing agreements for foreign technology was an especially attractive option. Manufacturing licensed products generated employment and empowered local industry while reducing dependence on imports. It also avoided

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