The Bell UH-1 Iroquois military helicopter, first introduced in 1959, is the first production member of the prolific Huey family of helicopters, and was itself developed in over twenty variants, which are listed below.
66-488: The first Bell helicopter to use a turbine engine was a modified Model 47 (designated XH-13F ), which had its initial flight in October 1954. The U.S. Army began a competition for a new helicopter for general utility and medical/casualty evacuation in 1955. In June 1955, Bell Helicopter was awarded a contract to develop the next generation turbine-powered utility helicopter for the U.S. Army. The resulting Bell Model 204
132-565: A CGS unit of acceleration . The gallon currently has one definition in the imperial system, and two definitions (liquid and dry ) in the US customary system. Historically, there were many definitions and redefinitions. There were a number of systems of liquid measurements in the United Kingdom prior to the 19th century. The British imperial gallon (frequently called simply "gallon") is defined as exactly 4.54609 dm (4.54609 litres). It
198-801: A Bell 47J with an unclad, tubular tail boom, and powered by a Turbomeca Astazou II turboshaft engine Meridionali/Agusta EMA 124 Italian prototype with redesigned forward fuselage. Not produced. Kawasaki KH-4 Japanese production version with redesigned, lengthened cabin, and redesigned control system Carson Super C-4 El Tomcat Mk.II Bell 47G-2 modified extensively for agricultural spraying by Continental Copters Inc. First flew in April 1959, followed by further improved versions. Data from International Directory of Civil Aircraft General characteristics Performance Related development Aircraft of comparable role, configuration, and era Related lists US gallon The gallon
264-411: A US fluid ounce is 1 / 16 of a US pint, or 1 / 128 of a US gallon. Thus, the imperial gallon, quart, pint, cup and gill are approximately 20% larger than their US counterparts, meaning these are not interchangeable, but the imperial fluid ounce is only approximately 4% smaller than the US fluid ounce, meaning these are often used interchangeably. Historically,
330-422: A US gallon. In order to overcome the effects of expansion and contraction with temperature when using a gallon to specify a quantity of material for purposes of trade, it is common to define the temperature at which the material will occupy the specified volume. For example, the volume of petroleum products and alcoholic beverages are both referenced to 60 °F (15.6 °C) in government regulations. Since
396-664: A common bottle size for liquor in the US was the " fifth ", i.e. one-fifth of a US gallon (or one-sixth of an imperial gallon). While spirit sales in the US were switched to metric measures in 1976, a 750 mL bottle is still sometimes known as a "fifth". The term derives most immediately from galun , galon in Old Norman French , but the usage was common in several languages, for example jale in Old French and gęllet (bowl) in Old English. This suggests
462-522: A common origin in Romance Latin , but the ultimate source of the word is unknown. The gallon originated as the base of systems for measuring wine and beer in England. The sizes of gallon used in these two systems were different from each other: the first was based on the wine gallon (equal in size to the US gallon), and the second one either the ale gallon or the larger imperial gallon. By
528-472: A few and found that the type would suit their uses as a utility helicopter. On 16 May 1968, the US Navy ordered eight aircraft under the designation UH-1L. Bell 47 The Bell 47 is a single-rotor single-engine light helicopter manufactured by Bell Helicopter . It was based on the third Bell 30 prototype, which was the company's first helicopter designed by Arthur M. Young . The 47 became
594-555: A fully enclosed cabin and tail boom. Early models varied in appearance, with open cockpits or sheet metal cabins, fabric covered or open structures, some with four-wheel landing gear. Later model D and Korean War H-13D and E types settled on a more utilitarian style. The most common model, the 47G introduced in 1953, can be recognized by the full "soap bubble" canopy , exposed welded-tube tail boom, saddle fuel tanks and skid landing gear. The later three-seat 47H had an enclosed cabin with full cowling and monocoque tail boom. It
660-679: A gunship and troop transport. Many were upgraded to the Lycoming T53-L-13 engine which produced 1,400 shp (1,000 kW), making these "Echos" similar to the Army "Mike" models. At least 126 UH-1Es survived their Vietnam service and were still in use more than a decade later. There was a Marine Corps training version of the UH-1E, which was based on the UH-1C variant and was designated TH-1E . Twenty were delivered in 1965. Bell Helicopters
726-595: A longer cabin that could accommodate seven passengers. This version was redesignated UH-1B in 1962. Later production UH-1Bs were equipped with Lycoming T53-L-9 and L-11 engines of 1,100 shp (820 kW). Gross weight was 8,500 lb (3,900 kg) and the standard empty weight was 4,513 lb (2,047 kg). Army testing of the "B" model started in November 1960 with first production aircraft arriving in March 1961. A total of 1010 "Bravo" models were delivered to
SECTION 10
#1732779774155792-452: A new tailboom for the "C" which incorporated a wider chord fin on a longer boom and larger synchronized elevators. The "C" 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. Fuel was increased to 242 US gallons and gross weight to 9,500 lb (4,300 kg), giving a nominal useful load of 4,673 lb (2,120 kg). Development on
858-621: A number of Bell 47s during the Apollo program , used by astronauts as trainers for the lunar lander . Apollo 17 commander Eugene Cernan had a nearly disastrous crash into the Indian River in Florida in 1971, before his flight to the Moon. The 47 has also served as the helicopter of choice for basic helicopter flight instruction in many countries. Agusta A.115 1971 Italian prototype of
924-579: A rescue hoist located at the right side of the cabin. The last UH-1F was retired from the USAF in the early 1980s when it was replaced by the air rescue version of the UH-1H which itself was replaced by the air rescue versions of the UH-1N in the mid 1990s. 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
990-406: A rotor brake to stop the rotor quickly on shutdown for shipboard use 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
1056-556: A small "hinged panel" with an optional window, providing access to the cabin. The doors and hinged panels were quickly removable and the Huey could be flown in that configuration. The first YUH-1D prototype flew in August 1960. Seven YUH-1Ds were delivered and tested at Edwards AFB starting in March 1961. The YUH-1D was initially equipped with a 44 ft (13 m) main rotor and a Lycoming T53-L-9 engine. Testing revealed that more power
1122-472: A success, especially in the gunship role, but lacked the cabin space to be an effective troop transport. The US Army wanted a version that could carry a crew of four (two pilots and two door gunners) and also deliver an infantry section of eight to ten soldiers. Bell's solution was to stretch the UH-1B fuselage by 41 inches (105 cm) and use the extra space to fit two sideways-facing seats on either side of
1188-476: A view soon adopted by the Army; they found the pre-production aircraft so much better in service than previous piston-powered helicopters that they soon ordered more. The HU-1A (later redesignated the UH-1A) was the first turbine-equipped U.S. helicopter to go into production, and production models first entered service with the 101st Airborne Division at Fort Campbell, Kentucky , the 82nd Airborne Division and
1254-469: Is a unit of volume in British imperial units and United States customary units . Three different versions are in current use: There are two pints in a quart and four quarts in a gallon. Different sizes of pints account for the different sizes of the imperial and US gallons. The IEEE standard symbol for both US (liquid) and imperial gallon is gal , not to be confused with the gal (symbol: Gal),
1320-412: Is legally defined as 231 cubic inches , which is exactly 3.785411784 litres. A US liquid gallon can contain about 3.785 kilograms or 8.34 pounds of water at 3.98 °C (39.16 °F), and is about 16.7% less than the imperial gallon. There are four quarts in a gallon, two pints in a quart and 16 US fluid ounces in a US pint , which makes the US fluid ounce equal to 1 / 128 of
1386-662: Is used as the primary fuel economy unit in the United Kingdom and as a supplementary unit in Canada on official documentation. Other than the United States, petrol is sold by the US gallon in 13 other countries, and one US territory: The latest country to cease using the gallon is El Salvador in June 2021. Both the US gallon and imperial gallon are used in the Turks and Caicos Islands (due to an increase in tax duties which
SECTION 20
#17327797741551452-418: Is used in some Commonwealth countries, and until 1976 was defined as the volume of water at 62 °F (16.67 °C) whose mass is 10 pounds (4.5359237 kg). There are four imperial quarts in a gallon, two imperial pints in a quart, and there are 20 imperial fluid ounces in an imperial pint, yielding 160 fluid ounces in an imperial gallon. The US liquid gallon (frequently called simply "gallon")
1518-546: The 57th Medical Detachment . Although they were intended for evaluation only, the Army quickly pressed them into operational service and Hueys with the 57th Medical Detachment arrived in South Vietnam in March 1962. The helicopter was originally designated the HU-1A, which is where it received its nickname - "Huey." The official U.S. Army designation Iroquois (Army helicopters are traditionally given Native American names)
1584-567: The European Union the gallon was removed from the list of legally defined primary units of measure catalogue in the EU directive 80/181/EEC for trading and official purposes, effective from 31 December 1994. Under the directive the gallon could still be used, but only as a supplementary or secondary unit. As a result of the EU directive Ireland and the United Kingdom passed legislation to replace
1650-468: The Lycoming T53-L-11 of 1,100 shp (820 kW). Because Bell was switching Army production to the UH-1C the UH-1E production line was converted to commonality with the "C". This meant the later "Echo" Hueys were completed with the "Charlie" style tailboom including the larger fin, the 540 rotor system and a gross weight of 8,500 lb (3,900 kg). The Marines used the UH-1E as both
1716-771: The Lycoming T53-L-13 powerplant of 1,400 shp (1,000 kW). Deliveries of the “Kilo” Huey started in May 1970 and by November of that year three had been sent to Vietnam to serve with US Navy squadron HA(L)-3 and, later with the HA(L)-4 Red Wolves and the HA(L)-5 Blue Hawks . A total of 27 HH-1Ks were produced. With deliveries of the UH-1E underway to the US Marines the US Navy tested
1782-602: The US Army , and during the Korean War , it served a variety of roles, including reconnaissance and scouting, search and rescue, and medevac. The "Telecopter" was a Bell 47 rented by television station KTLA in Los Angeles , California . It was outfitted with a television camera and it made the world ' s first flight by a television news helicopter on July 3, 1958, with its inventor, John D. Silva, aboard. When
1848-637: The West German armed forces. The HH-1D was a base rescue/fire-fighting version for the US Army that had a 50-gallon water and foam spray system that could be discharged via an extendable 16-foot (4.9 m) boom. Upgrading the UH-1D to the Lycoming T53-L-13 engine, plus relocating the pitot tube from the nose to the roof resulted in a new model, the UH-1H, which was to become the most produced variant of
1914-459: The dry measure is one-eighth of a US Winchester bushel of 2,150.42 cubic inches, it is equal to exactly 268.8025 cubic inches, which is 4.404 883 770 86 L . The US dry gallon is not used in commerce, and is also not listed in the relevant statute, which jumps from the dry pint to the bushel. As of 2021, the imperial gallon continues to be used as the standard petrol unit on 10 Caribbean island groups , consisting of: All 12 of
1980-535: The kilogram -litre relationship , the imperial gallon was based on the volume of 10 pounds of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury (100 kilopascals ; 15 pounds per square inch ) and at a temperature of 62 °F (17 °C). In 1963, this definition was refined as the space occupied by 10 pounds of distilled water of density 0.998 859 g/mL weighed in air of density 0.001 217 g/mL against weights of density 8.136 g/mL (the original "brass"
2046-483: The "C" model had commenced in 1960, with production starting in June 1966. A total of 766 "C" models were completed, including five for the Royal Australian Navy and five for Norway. The balance went to the US Army. Many UH-1Cs were later re-engined with the 1,400 shp (1,000 kW) Lycoming T53-L-13 powerplant. With this engine they were redesignated UH-1M . The earlier "short-body" Hueys were
Bell UH-1 Iroquois variants - Misplaced Pages Continue
2112-496: The "Delta" model were on 9 August 1963 when the 11th Air Assault Division (Test) at Fort Benning Georgia received two. This unit was renamed the 1st Cavalry Division and deployed to Vietnam with its "Delta" Hueys. A total of 2,008 UH-1Ds were delivered to the US Army between 1962 and 1966. The model was widely exported and served with the armed forces of Australia and South Vietnam among others. A grand total of 2,561 UH-1Ds were built, including 352 constructed by Dornier for
2178-692: The Autonomous Aerial Cargo Utility System (AACUS) program. The Bell Huey II is a re-manufactured, modified and re-engined military UH-1H, including an Allison T53-L-703 turboshaft engine of 1,800 shp (1,343 kW), a vibration-reduction system, infrared countermeasures and a night-vision-goggle (NVG) compatible cockpit. Currently offered by Bell. Some UH-1Hs built by Fuji in Japan for the Japan Ground Self-Defense Force were improved and given
2244-473: The Caribbean islands use miles per hour for speed limits signage, and drive on the left side of the road . The United Arab Emirates ceased selling petrol by the imperial gallon in 2010 and switched to the litre, with Guyana following suit in 2013. In 2014, Myanmar switched from the imperial gallon to the litre. Antigua and Barbuda has proposed switching to selling petrol by litres since 2015. In
2310-612: The Huey family. In 1962 the US Marines held a competition to choose a new assault support helicopter to replace the Cessna O-1 and Kaman OH-43D helicopter. The winner was the UH-1B which was already then in service with the US Army. The UH-1B was developed into a special model, designated UH-1E, to meet Marine Corps requirements. The major changes included the use of all-aluminum construction for corrosion resistance (earlier UH-1s had some magnesium components), special avionics that were compatible with Marine Corps ground frequencies,
2376-543: The T58 engine backwards compared to the HH-3. The Huey's engine is behind the transmission, whereas the HH-3's engines are in front of 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. The UH-1F was introduced into the USAF inventory on 20 February 1964. The USAF took delivery of 119 with production ending in 1967. Many of
2442-601: The UH-1H for the civil market. The aircraft incorporated minor changes for safety, such as dual sliding door locks and a baggage compartment in the tailboom. It was marketed by Bell as the Model 205A and later the improved 205A-1. The "Hotel" model Huey was also the basis for a number of sub-variants: A UAV version of UH-1H is being developed by Aurora Flight Sciences using the Tactical Autonomous Aerial Logistics System platform for
2508-512: The US Army. First deployment was in November 1963 when eleven were sent to Vietnam to join the "Alpha" models already in use by UTTCO. One NUH-1B was produced for test purposes. Bell certified a civil version of the UH-1B incorporating some minor safety improvements, such as improved door locks. The aircraft was marketed as the Bell 204B . Later on as the "long cabin" Hueys supplanted the Bravo in
2574-468: The US), which in turn are further divided into two gills . Thus, both gallons are equal to four quarts, eight pints, sixteen cups, or thirty-two gills. The imperial gill is further divided into five fluid ounces, whereas the US gill is divided into four fluid ounces, meaning an imperial fluid ounce is 1 / 20 of an imperial pint, or 1 / 160 of an imperial gallon, while
2640-596: The USAF. The first TH-1F was flown in January 1967 and deliveries ran from April to July of that year with 27 completed. Examples of this variant were operated by the USAF Instrument Flight Center. The UH-1H was an improved UH-1D, with the Lycoming T53-L-13 engine of 1,400 shp (1,000 kW) installed, plus the pitot tube relocated from the nose to the roof, to reduce ground damage to it. "Hotel" models were created by upgrading "Deltas" with
2706-713: The United Kingdom. Bell 47s were produced in Japan by a Bell and Kawasaki venture; this led to the Kawasaki KH-4 variant, a four-seat version of the Model 47 with a cabin similar to the Bell 47J. It differed from the "J" in having a standard uncovered tail boom and fuel tanks like the G series. It was sold throughout Asia, and some were used in Australia. In February 2010, the Bell 47 type certificates were transferred to Scott's Helicopter Services . The sister company that
Bell UH-1 Iroquois variants - Misplaced Pages Continue
2772-485: The aircraft served in southeast Asia with the 20th Special Operations Squadron and some were converted to the armed UH-1P configuration. In Italy, Agusta produced a similar model by re-engining the 204B with the 1,225 hp (914 kW) Rolls-Royce Gnome (license-built T58) turboshaft, but later models used T58s. The AB204B was exported to the military of the Netherlands, Sweden, Austria, and Switzerland. It had
2838-420: The bushel 8 in × ( 9 + 1 / 4 in) × π ≈ 2150.42017 cubic inches . The bushel was later defined to be 2150.42 cubic inches exactly, thus making its gallon exactly 268.8025 in ( 4.404 883 770 86 L ); in previous centuries, there had been a corn gallon of between 271 and 272 cubic inches. The wine , fluid , or liquid gallon has been the standard US gallon since
2904-466: The deficiencies of the UH-1B when it was used in the armed role. The UH-1C was widely referred to as the "Huey Hog" in US Army service. The "Charlie" model was fitted with the 1,100 shp (820 kW) T53-L-9 or L-11 engine to provide the power needed to lift the weapons systems in use or under development at the time. It incorporated the new Bell 540 rotor system with 27-inch (690 mm) chord blades. The increased power lead Bell's engineers to design
2970-511: The earlier definition with π approximated to 22 / 7 . π r 2 h ≈ 22 7 × ( 7 i n 2 ) 2 × 6 i n = 231 i n 3 . {\displaystyle \pi r^{2}h\approx {\frac {22}{7}}\times \left({\frac {7~\mathrm {in} }{2}}\right)^{2}\times 6~\mathrm {in} =231~\mathrm {in} ^{3}.} Although
3036-415: The early 19th century . The wine gallon, which some sources relate to the volume occupied by eight medieval merchant pounds of wine, was at one time defined as the volume of a cylinder 6 inches deep and 7 inches in diameter, i.e. 6 in × ( 3 + 1 / 2 in) × π ≈ 230.907 06 cubic inches . It was redefined during the reign of Queen Anne in 1706 as 231 cubic inches exactly,
3102-401: The end of the 18th century, there were three definitions of the gallon in common use: The corn or dry gallon is used (along with the dry quart and pint) in the United States for grain and other dry commodities. It is one-eighth of the (Winchester) bushel, originally defined as a cylindrical measure of 18 + 1 / 2 inches in diameter and 8 inches in depth, which made
3168-654: The fall of 1962. These aircraft were used as armed escorts to the existing H-21 Shawnees and H-34 Choctaws troop carriers. In use the UH-1A proved under-powered with their Lycoming T53-L-1 powerplants of just 860 shp and indicated the need for improved follow-on models of the Huey. The HU-1B was an improved model that was equipped with the Lycoming T53-L-5 engine of 960 shp (720 kW), revised main rotor blades of 44-foot (13 m) diameter and 21-inch (530 mm) chord, 13 inch higher rotor mast and
3234-455: The first helicopter certified for civilian use on 8 March 1946. The first civilian delivery was made on 31 December 1946 to Helicopter Air Transport . More than 5,600 Bell 47s were produced, including those under license by Agusta in Italy, Kawasaki Heavy Industries in Japan, and Westland Aircraft in the United Kingdom. The Bell 47J Ranger is a modified version with
3300-601: The first one delivered on 6 March 1968. These were evaluated by the Canadian Forces and found unsuitable for Canadian tactical use, which resulted in the Canadian government sponsoring the development of the twin-engined version of the "Hotel", the UH-1N Twin Huey . The ten CUH-1Hs were re-equipped for search and rescue use, redesignated CH-118 and served until 1995. Bell developed a certified version of
3366-519: The gallon with the litre as a primary unit of measure in trade and in the conduct of public business, effective from 31 December 1993, and 30 September 1995 respectively. Though the gallon has ceased to be a primary unit of trade, it can still be legally used in both the UK and Ireland as a supplementary unit. However, barrels and large containers of beer, oil and other fluids are commonly measured in multiples of an imperial gallon. Miles per imperial gallon
SECTION 50
#17327797741553432-523: The local designation of UH-1J, although this was not used in the US designation series. It has an upgraded engine and a UH-1N nose. Japan's UH-1H and UH-1Js will be replaced by a military version of the Bell 412 . Bell was awarded a contract by the US Navy in December 1968 for a new search and rescue helicopter. The aircraft was designated the HH-1K and was basically a UH-1E with different avionics and
3498-539: The more powerful engine. The first YUH-1H flew in 1966 with deliveries of production models starting in September 1967. The "Hotel" model Huey was produced in larger numbers than any other model, with 4,850 delivered to the US Army alone. The "Hotel" model was widely exported and was also built under license in Germany , Italy , Japan , and Taiwan . Ten were sold to Canada for use under the designation CUH-1H with
3564-582: The television station reported it was receiving no video, Silva exited the helicopter ' s cockpit to climb onto its landing skid while it hovered at 1,500 feet (457 m) so he could investigate the microwave transmitter bolted to its side, where he discovered a vacuum tube had failed due to vibration and hot weather. After Silva fixed the problem overnight, the Telecopter made the world's first successful television news flight on July 4, 1958. The National Aeronautics and Space Administration (NASA) had
3630-434: The transmission. This brought the total seating capacity to 15, including crew seats. The new Huey was designated UH-1D by the US Army and as the Model 205 by Bell. The enlarged cabin could also accommodate six stretchers, double that of the earlier models, making the "Delta" a good 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
3696-477: The transport role, the UH-1B became increasingly used in a "gunship" role equipped with machine guns and rockets. However, it had insufficient power to maintain full capability when used with the heaviest armament subsystems, leading to the UH-1C. The UH-1C was specifically developed as a gunship version until the "interim" attack helicopter, the Bell AH-1G Huey Cobra was available and to correct
3762-399: The types. This engine was capable of 1,250 hp (932 kW) compared to the UH-1B's 1,100 hp (820 kW) T53-L11. In response Bell proposed an upgraded version of the UH-1B with the T58 engine installed. The resulting UH-1F had the shorter cabin of the "Bravo" Huey, but with the longer tail boom, rotor and transmission of the UH-1D. Due to the Huey's configuration, Bell installed
3828-482: The wine gallon had been used for centuries for import duty purposes, there was no legal standard of it in the Exchequer , while a smaller gallon (224 cu in) was actually in use, requiring this statute; the 231 cubic inch gallon remains the US definition today. In 1824, Britain adopted a close approximation to the ale gallon known as the imperial gallon , and abolished all other gallons in favour of it. Inspired by
3894-491: Was almost never used in practice. Fourteen of the original order of UH-1As were designated as TH-1A which were used for crew training and a single aircraft was redesignated XH-1A for grenade launcher testing in 1960. The first UH-1As to arrive in Vietnam after the 57th Medical Detachment were with a new test unit, the US Army's Utility Tactical Transport Company (UTTCO). UTTCO had 20 "Alpha" Hueys and deployed to Vietnam in
3960-492: Was an attempt to market a "luxury" version of the basic 47G. Relatively few were produced. Engines were Franklin or Lycoming vertically mounted piston engines of 175 to 305 HP (130 to 227 kW ). Seating varied from two (early 47s and the later G-5A) to four (the J and KH-4). In April 2011 there were 1068 registered with the Federal Aviation Administration in the United States and 15 in
4026-504: Was designated XH-40 by the U.S. military and first flew on 22 October 1956. Two more prototypes were built in 1957, and six YH-40 pre-production helicopters were delivered in 1958. The YH-40's cabin was lengthened by 12 in (30 cm), and had more ground clearance compared to the XH-40. Bell believed the YH-40 was ideal for troop transport and cargo carrying as well as the medevac role,
SECTION 60
#17327797741554092-749: Was disguised by levying the same duty on the US gallon (3.79 L) as was previously levied on the Imperial gallon (4.55 L)) and the Bahamas . In some parts of the Middle East, such as the United Arab Emirates and Bahrain , 18.9-litre water cooler bottles are marketed as five-gallon bottles. Both the US liquid and imperial gallon are divided into four quarts ( quart er gallons), which in turn are divided into two pints , which in turn are divided into two cups (not in customary use outside
4158-421: Was formed, Scott's - Bell 47 , is in the process of starting production of a turboshaft powered version of the Bell 47, the 47GT-6, using a Rolls-Royce RR300 engine and with composite rotor blades, with deliveries planned from 2016. The Bell 47 entered US military service in late 1946, and operated in a variety of versions and under different designations for three decades. It was designated H-13 Sioux by
4224-407: Was refined as the densities of brass alloys vary depending on metallurgical composition), which was calculated as 4.546 091 879 L to ten significant figures. The precise definition of exactly 4.546 09 cubic decimetres (also 4.546 09 L , ≈ 277.419 433 in ) came after the litre was redefined in 1964. This was adopted shortly afterwards in Canada, and adopted in 1976 in
4290-503: Was required and so the rotor was lengthened to 48 ft (15 m) with a chord of 21 inches (530 mm) and the engine was upgraded to the Lycoming T53-L-11 engine of 1,100 shp (820 kW). A longer tailboom was designed to accommodate the longer rotor blades. Gross weight was 9,500 lb (4,300 kg). Later production "Deltas" had the Lycoming T53-L-13 powerplant of 1,400 shp (1,000 kW) installed and redesignated as "Hotel" models. The first Army unit deliveries of
4356-537: Was the winner of a 1963 United States Air Force competition for a support helicopter for use on its missile bases. Bell had proposed the UH-1B for the competition but the USAF asked Bell to develop a special version of the "Bravo" in using the General Electric T58 turboshaft as a powerplant. The USAF already had a large inventory of these engines for its fleet of Sikorsky HH-3 Jolly Green Giant rescue helicopters and wanted to have commonality between
#154845