89-639: The Sikorsky H-5 (initially designated R-5 and also known as S-48 , S-51 and by company designation VS-327 ) is a helicopter built by Sikorsky Aircraft Corporation . It was used by the United States Air Force , and its predecessor, the United States Army Air Forces , as well as the United States Navy and United States Coast Guard (with the designations HO2S and HO3S ). It was also used by
178-616: A runway . In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production . Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter , not to be confused with the single-blade monocopter ) has become the most common helicopter configuration. However, twin-rotor helicopters (bicopters), in either tandem or transverse rotors configurations, are sometimes in use due to their greater payload capacity than
267-444: A collective input is made, all the blades change equally, and the result is the helicopter increasing or decreasing in altitude. A swashplate controls the collective and cyclic pitch of the main blades. The swashplate moves up and down, along the main shaft, to change the pitch of both blades. This causes the helicopter to push air downward or upward, depending on the angle of attack . The swashplate can also change its angle to move
356-417: A constant altitude. The pedals serve the same function in both a helicopter and a fixed-wing aircraft, to maintain balanced flight. This is done by applying a pedal input in whichever direction is necessary to center the ball in the turn and bank indicator . Due to the operating characteristics of the helicopter—its ability to take off and land vertically, and to hover for extended periods of time, as well as
445-592: A few more flights and achieved a height of nearly 2.0 metres (6.5 ft), but it proved to be unstable and was abandoned. USS Leyte (CV-32) USS Leyte (CV/CVA/CVS-32, AVT-10) was one of 24 Essex -class aircraft carriers built during and shortly after World War II for the United States Navy . The ship was the third US Navy ship to bear the name. Leyte was commissioned in April 1946, too late to serve in World War II. She spent most of her career in
534-463: A gift by their father, would inspire the Wright brothers to pursue the dream of flight. In 1861, the word "helicopter" was coined by Gustave de Ponton d'Amécourt , a French inventor who demonstrated a small steam-powered model. While celebrated as an innovative use of a new metal, aluminum, the model never lifted off the ground. D'Amecourt's linguistic contribution would survive to eventually describe
623-405: A helicopter determines the size, function and capability of that helicopter design. The earliest helicopter engines were simple mechanical devices, such as rubber bands or spindles, which relegated the size of helicopters to toys and small models. For a half century before the first airplane flight, steam engines were used to forward the development of the understanding of helicopter aerodynamics, but
712-510: A helicopter powered by a gasoline engine with box kites attached to a mast by cables for a rotor, but it never flew. In 1906, two French brothers, Jacques and Louis Breguet , began experimenting with airfoils for helicopters. In 1907, those experiments resulted in the Gyroplane No.1 , possibly as the earliest known example of a quadcopter. Although there is some uncertainty about the date, sometime between 14 August and 29 September 1907,
801-416: A helicopter. This is because a helicopter generates its own gusty air while in a hover, which acts against the fuselage and flight control surfaces. The result is constant control inputs and corrections by the pilot to keep the helicopter where it is required to be. Despite the complexity of the task, the control inputs in a hover are simple. The cyclic is used to eliminate drift in the horizontal plane, that
890-683: A new, longer fuselage for two persons in tandem, though it retained the R-4's tailwheel-type landing gear . Larger than the R-4 or the later R-6 , the R-5 was fitted with a more powerful Wasp Junior 450-hp radial engine, and quickly proved itself the most successful of the three types. The first XR-5 of four ordered made its initial flight on 18 August 1943. In March 1944, the Army Air Forces ordered 26 YR-5A s for service testing, and in February 1945,
979-708: A number of Air Force pilots for a month, cross-training for carrier-based operations. Notable pilots participating in those exercises included Kenneth O. Chilstrom and George I. Ruddell . The deployment of Leyte to the Mediterranean in mid-1950 included a demonstration of airpower over Beirut , Lebanon , on 14 August, supporting the Middle East against communist pressure. Leyte returned to Norfolk on 24 August, and after two weeks of preparation, departed on 6 September to join Task Force 77 (TF 77) in
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#17327913511981068-477: A process of rebracketing , the word is often (erroneously, from an etymological point of view) perceived by English speakers as consisting of heli- and -copter , leading to words like helipad and quadcopter . English language nicknames for "helicopter" include "chopper", "copter", "heli", and "whirlybird". In the United States military, the common slang is "helo" pronounced /ˈhiː.loʊ/. A helicopter
1157-667: A redesigned tricycle landing gear configuration; this first flew on 16 February 1946. With room for three passengers plus pilot, the S-51 was initially intended to appeal to civilian as well as military operators, and was the first helicopter to be sold to a commercial user. Eleven S-51s were ordered by the USAF and designated the R-5F , while 92 went to the Navy as the HO3S-1 , commonly referred to as
1246-494: A rotor. The spinning creates lift, and the toy flies when released. The 4th-century AD Daoist book Baopuzi by Ge Hong ( 抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft. Designs similar to the Chinese helicopter toy appeared in some Renaissance paintings and other works. In the 18th and early 19th centuries Western scientists developed flying machines based on
1335-441: A single main rotor, but torque created by its aerodynamic drag must be countered by an opposed torque. The design that Igor Sikorsky settled on for his VS-300 was a smaller tail rotor. The tail rotor pushes or pulls against the tail to counter the torque effect, and this has become the most common configuration for helicopter design, usually at the end of a tail boom . Some helicopters use other anti-torque controls instead of
1424-417: A state called translational lift which provides extra lift without increasing power. This state, most typically, occurs when the airspeed reaches approximately 16–24 knots (30–44 km/h; 18–28 mph), and may be necessary for a helicopter to obtain flight. In forward flight a helicopter's flight controls behave more like those of a fixed-wing aircraft. Applying forward pressure on the cyclic will cause
1513-614: A temporary license, the S-51 gained full Civil Aeronautics Authority (CAA) certification for commercial operation on April 17, 1947. In the United Kingdom, the first scheduled daily helicopter service started in June 1950 between Liverpool and Cardiff using S-51s operated by British European Airways (BEA). Data from: Aerofiles : Sikorsky Data from United States Military Aircraft since 1909 General characteristics Performance Helicopter A helicopter
1602-503: A total of 88 HO3S-1 (S-51) helicopters. Thirty-nine additional specialized rescue helicopters were built, as the H-5G , in 1948, while 16 were fitted with pontoons as the H-5H amphibian in 1949. Several H-5Hs were converted in 1949 to a unique medical-evacuation role, with casualty stretchers loaded sideways through blister-hatches on the side of the fuselage. The back stretcher station
1691-560: A very slow 25 knots (46 km/h; 29 mph). The H-5/HO3S-1 gained its greatest fame during the Korean War when it was called upon repeatedly to rescue United Nations pilots shot down behind enemy lines and to evacuate wounded personnel from frontline areas. It was eventually replaced in most roles by the H-19 Chickasaw . In 1957, the last H-5 and HO3S-1 helicopters were retired from active U.S. military service. The S-51
1780-429: Is a cylindrical metal shaft that extends upwards from the transmission. At the top of the mast is the attachment point for the rotor blades called the hub. Main rotor systems are classified according to how the rotor blades are attached and move relative to the hub. There are three basic types: hingeless, fully articulated, and teetering; although some modern rotor systems use a combination of these. Most helicopters have
1869-460: Is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors . This allows the helicopter to take off and land vertically , to hover , and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of short take-off and landing ( STOL ) or short take-off and vertical landing ( STOVL ) aircraft cannot perform without
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#17327913511981958-452: Is a type of rotorcraft in which lift and thrust are supplied by one or more horizontally-spinning rotors. By contrast the autogyro (or gyroplane) and gyrodyne have a free-spinning rotor for all or part of the flight envelope, relying on a separate thrust system to propel the craft forwards, so that the airflow sets the rotor spinning to provide lift. The compound helicopter also has a separate thrust system, but continues to supply power to
2047-452: Is called an aerial crane . Aerial cranes are used to place heavy equipment, like radio transmission towers and large air conditioning units, on the tops of tall buildings, or when an item must be raised up in a remote area, such as a radio tower raised on the top of a hill or mountain. Helicopters are used as aerial cranes in the logging industry to lift trees out of terrain where vehicles cannot travel and where environmental concerns prohibit
2136-489: Is equipped to stabilize and provide limited medical treatment to a patient while in flight. The use of helicopters as air ambulances is often referred to as " MEDEVAC ", and patients are referred to as being "airlifted", or "medevaced". This use was pioneered in the Korean War , when time to reach a medical facility was reduced to three hours from the eight hours needed in World War II , and further reduced to two hours by
2225-678: Is the Sud-Ouest Djinn , and an example of the hot tip jet helicopter is the YH-32 Hornet . Some radio-controlled helicopters and smaller, helicopter-type unmanned aerial vehicles , use electric motors or motorcycle engines. Radio-controlled helicopters may also have piston engines that use fuels other than gasoline, such as nitromethane . Some turbine engines commonly used in helicopters can also use biodiesel instead of jet fuel. There are also human-powered helicopters . A helicopter has four flight control inputs. These are
2314-411: Is to control forward and back, right and left. The collective is used to maintain altitude. The pedals are used to control nose direction or heading . It is the interaction of these controls that makes hovering so difficult, since an adjustment in any one control requires an adjustment of the other two, creating a cycle of constant correction. As a helicopter moves from hover to forward flight it enters
2403-489: The Atlantic , Caribbean , and Mediterranean , but also saw service in the Korean War , in which she earned two battle stars . She was reclassified in the early 1950s as an attack carrier (CVA), then as an Antisubmarine Aircraft Carrier (CVS), and finally (after inactivation) as an aircraft transport (AVT). Unlike most of her sister ships , Leyte received no major modernizations, and thus throughout her career retained
2492-572: The Bell 205 and the Erickson S-64 Aircrane helitanker. Helicopters are used as air ambulances for emergency medical assistance in situations when an ambulance cannot easily or quickly reach the scene, or cannot transport the patient to a medical facility in time. Helicopters are also used when patients need to be transported between medical facilities and air transportation is the most practical method. An air ambulance helicopter
2581-588: The Bell 206 with 3,400. Most were in North America with 34.3% then in Europe with 28.0% followed by Asia-Pacific with 18.6%, Latin America with 11.6%, Africa with 5.3% and Middle East with 1.7%. The earliest references for vertical flight came from China. Since around 400 BC, Chinese children have played with bamboo flying toys (or Chinese top). This bamboo-copter is spun by rolling a stick attached to
2670-527: The Cornu helicopter which used two 6.1-metre (20 ft) counter-rotating rotors driven by a 24 hp (18 kW) Antoinette engine. On 13 November 1907, it lifted its inventor to 0.3 metres (1 ft) and remained aloft for 20 seconds. Even though this flight did not surpass the flight of the Gyroplane No. 1, it was reported to be the first truly free flight with a pilot. Cornu's helicopter completed
2759-663: The Far East to support United Nations Forces in Korea . Leyte arrived at the Sasebo base for U.S. Fleet Activities in Sasebo , Japan , on 8 October 1950 and made final preparations for combat operations. From 9 October – 19 January 1951, the ship and her aircraft spent 92 days at sea and flew 3,933 sorties against North Korean forces. Her pilots accumulated 11,000 hours in the air while inflicting massive damage upon enemy positions, supplies, transportation, and communications. Among
Sikorsky H-5 - Misplaced Pages Continue
2848-491: The South Boston Naval Annex and still under conversion to an antisubmarine carrier, Leyte suffered an explosion in her port catapult machinery room. Within minutes, naval base and city fire trucks were on the scene. After a hard and gallant fight, the fire was extinguished at 19:57. As a result of the fire, 37 men (including five civilians) died and 28 were injured. It remains the largest loss of life on
2937-746: The United States Post Office Department . The civilian version, under the designation S-51, was the first helicopter to be operated commercially, commencing in 1946. In December 1946, an agreement was signed between the British company Westland Aircraft and Sikorsky to produce a British version of the H-5, to be manufactured under license in Britain as the Westland-Sikorsky WS-51 Dragonfly . By
3026-499: The Vietnam War . In naval service a prime function of rescue helicopters is to promptly retrieve downed aircrew involved in crashes occurring upon launch or recovery aboard aircraft carriers. In past years this function was performed by destroyers escorting the carrier, but since then helicopters have proved vastly more effective. Police departments and other law enforcement agencies use helicopters to pursue suspects and patrol
3115-621: The 'Horse'. In Britain, Westland Aircraft began production in 1946 of the Westland-Sikorsky S-51 Dragonfly for the Royal Navy and the Royal Air Force, all of which were powered by a 500 hp Alvis Leonides engine. This gave an improved top speed of 103 mph and a service ceiling of 14,000 ft. In total, 133 Westland-Sikorsky Dragonfly helicopters were built. A considerably modified version
3204-558: The Bambi bucket, are usually filled by submerging the bucket into lakes, rivers, reservoirs, or portable tanks. Tanks fitted onto helicopters are filled from a hose while the helicopter is on the ground or water is siphoned from lakes or reservoirs through a hanging snorkel as the helicopter hovers over the water source. Helitack helicopters are also used to deliver firefighters, who rappel down to inaccessible areas, and to resupply firefighters. Common firefighting helicopters include variants of
3293-721: The Boston waterfront. On 26 February 1955, Hans Anton Michelberger, a fireman apprentice from Old Bridge, New Jersey , was swept overboard and lost at sea; his body was not recovered. The builder's plaque from Leyte is in the collection of the Naval History and Heritage Command . A historical marker honoring Leyte is located in Charlestown, Boston , near the USS Constitution . The inscription reads, in part: "In memory of our shipmates and civilians lost in
3382-762: The Chinese top in a model consisting of contrarotating turkey flight feathers as rotor blades, and in 1784, demonstrated it to the French Academy of Sciences . Sir George Cayley , influenced by a childhood fascination with the Chinese flying top, developed a model of feathers, similar to that of Launoy and Bienvenu, but powered by rubber bands. By the end of the century, he had progressed to using sheets of tin for rotor blades and springs for power. His writings on his experiments and models would become influential on future aviation pioneers. Alphonse Pénaud would later develop coaxial rotor model helicopter toys in 1870, also powered by rubber bands. One of these toys, given as
3471-478: The Chinese toy. It was not until the early 1480s, when Italian polymath Leonardo da Vinci created a design for a machine that could be described as an " aerial screw ", that any recorded advancement was made towards vertical flight. His notes suggested that he built small flying models, but there were no indications for any provision to stop the rotor from making the craft rotate. As scientific knowledge increased and became more accepted, people continued to pursue
3560-453: The Gyroplane No. 1 lifted its pilot into the air about 0.6 metres (2 ft) for a minute. The Gyroplane No. 1 proved to be extremely unsteady and required a man at each corner of the airframe to hold it steady. For this reason, the flights of the Gyroplane No. 1 are considered to be the first manned flight of a helicopter, but not a free or untethered flight. That same year, fellow French inventor Paul Cornu designed and built
3649-534: The Marine Corps had equipped HMX-1, its first regular Marine Helicopter Transport Squadron, with six HO3S-1 aircraft. With a passenger load of only three lightly dressed persons, the HO3S-1s were primarily operated in the utility role by the marines; for the transport role, an additional nine tandem-rotor Piasecki-built HRP-1 helicopters were later added to the squadron. Eventually, the U.S. Navy would acquire
Sikorsky H-5 - Misplaced Pages Continue
3738-571: The Martian atmosphere is 100 times thinner than Earth's, its two blades spin at close to 3,000 revolutions a minute, approximately 10 times faster than that of a terrestrial helicopter. In 2017, 926 civil helicopters were shipped for $ 3.68 billion, led by Airbus Helicopters with $ 1.87 billion for 369 rotorcraft, Leonardo Helicopters with $ 806 million for 102 (first three-quarters only), Bell Helicopter with $ 696 million for 132, then Robinson Helicopter with $ 161 million for 305. By October 2018,
3827-478: The Mediterranean on 29 August 1952. Reclassified CVA-32 on 1 October, she returned to Boston on 16 February 1953 for deactivation. On 8 August, however, she was ordered to be retained in the active fleet, and, redesignated CVS-32 on the same day, work was begun converting her to an ASW carrier . Conversion completed on 4 January 1954, Leyte departed Boston for Quonset Point , Rhode Island , as flagship of Carrier Division 18 (CarDiv 18). She remained there for
3916-567: The United States Army Air Forces system, a series starting with R-1 and proceeding up to about R-16. In 1947 with the start of the United States Air Force, there was a new system, and many aircraft, but not all, were redesignated. The R-5 became the H-5. The United States Army broke off with its own designation system in the 1950s, resulting in new designations for its helicopter projects. In 1962 under
4005-550: The aircraft's handling properties under low airspeed conditions—it has proved advantageous to conduct tasks that were previously not possible with other aircraft, or were time- or work-intensive to accomplish on the ground. Today, helicopter uses include transportation of people and cargo, military uses, construction, firefighting, search and rescue , tourism , medical transport, law enforcement, agriculture, news and media , and aerial observation , among others. A helicopter used to carry loads connected to long cables or slings
4094-466: The aviation industry; and the turboshaft engine for helicopter use, pioneered in December 1951 by the aforementioned Kaman K-225, finally gave helicopters an engine with a large amount of power and a low weight penalty. Turboshafts are also more reliable than piston engines, especially when producing the sustained high levels of power required by a helicopter. The turboshaft engine was able to be scaled to
4183-435: The blades angle forwards or backwards, or left and right, to make the helicopter move in those directions. The anti-torque pedals are located in the same position as the rudder pedals in a fixed-wing aircraft, and serve a similar purpose, namely to control the direction in which the nose of the aircraft is pointed. Application of the pedal in a given direction changes the pitch of the tail rotor blades, increasing or reducing
4272-677: The building of roads. These operations are referred to as longline because of the long, single sling line used to carry the load. In military service helicopters are often useful for delivery of outsized slung loads that would not fit inside ordinary cargo aircraft: artillery pieces, large machinery (field radars, communications gear, electrical generators), or pallets of bulk cargo. In military operations these payloads are often delivered to remote locations made inaccessible by mountainous or riverine terrain, or naval vessels at sea. In electronic news gathering , helicopters have provided aerial views of some major news stories, and have been doing so, from
4361-953: The carrier was equipped with its first helicopter detachment of HO3S-1 utility helicopters, and participated in a fleet exercise, Operation Frigid , in the North Atlantic. In the years preceding the Korean War, the Leyte participated in numerous other fleet exercises in the Atlantic and Caribbean, trained naval reservists, and deployed four times to the Mediterranean : April–June 1947, July–November 1947, September 1949 – January 1950, and May–August 1950. Beginning in September 1948, while in Guantanamo Bay , Leyte hosted
4450-483: The classic appearance of a World War II Essex -class ship. She was decommissioned in 1959 and sold for scrap in 1970. Leyte was one of the "long-hull" Essex -class ships. She was laid down as Crown Point on 21 February 1944 at the Newport News Shipbuilding & Dry Dock Co., Newport News, Virginia , and renamed Leyte on 8 May 1945 to commemorate the recent Battle of Leyte Gulf . She
4539-406: The cockpit from overhead. The control is called the cyclic because it changes cyclic pitch of the main blades. The result is to tilt the rotor disk in a particular direction, resulting in the helicopter moving in that direction. If the pilot pushes the cyclic forward, the rotor disk tilts forward, and the rotor produces a thrust in the forward direction. If the pilot pushes the cyclic to the side,
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#17327913511984628-470: The cyclic, the collective, the anti-torque pedals, and the throttle. The cyclic control is usually located between the pilot's legs and is commonly called the cyclic stick or just cyclic . On most helicopters, the cyclic is similar to a joystick. However, the Robinson R22 and Robinson R44 have a unique teetering bar cyclic control system and a few helicopters have a cyclic control that descends into
4717-536: The early 21st century, as well as recently weaponized utilities such as artillery spotting , aerial bombing and suicide attacks . The English word helicopter is adapted from the French word hélicoptère , coined by Gustave Ponton d'Amécourt in 1861, which originates from the Greek helix ( ἕλιξ ), genitive helikos (ἕλῐκος), "helix, spiral, whirl, convolution" and pteron ( πτερόν ) "wing". In
4806-439: The event was taken by Max Skladanowsky , but it remains lost . In 1885, Thomas Edison was given US$ 1,000 (equivalent to $ 34,000 today) by James Gordon Bennett, Jr. , to conduct experiments towards developing flight. Edison built a helicopter and used the paper for a stock ticker to create guncotton , with which he attempted to power an internal combustion engine. The helicopter was damaged by explosions and one of his workers
4895-572: The first African-American to complete the Navy's basic flight training program, Ensign Jesse L. Brown , who was assigned to Fighter Squadron 32 (VF-32) aboard Leyte , was killed in action while supporting ground troops at the Battle of Chosin Reservoir . Brown's wingman, Thomas J. Hudner Jr. , was awarded the Medal of Honor for attempting to save Brown's life. At 15:15 on 16 October 1953, while at
4984-506: The first YR-5A was delivered. This order was followed by a production contract for 100 R-5s, outfitted with racks for two litters (stretchers), but only 34 were actually delivered. Of these, fourteen were the R-5A , basically identical with the YR-5A. The remaining twenty were built as the three-place R-5D , which had a widened cabin with a two-place rear bench seat and a small nosewheel added to
5073-486: The first half of the 20th century was that the amount of power produced by an engine was not able to overcome the engine's weight in vertical flight. This was overcome in early successful helicopters by using the smallest engines available. When the compact, flat engine was developed, the helicopter industry found a lighter-weight powerplant easily adapted to small helicopters, although radial engines continued to be used for larger helicopters. Turbine engines revolutionized
5162-461: The first helicopter to fly in the Antarctic. Having proved its capabilities, the initial naval HO3S-1 order was followed by subsequent purchases of an additional 42 aircraft in 1948. The Navy equipped several warship classes with HO3S-1 utility helos, including aircraft carriers , seaplane tenders, icebreakers , Des Moines -class cruisers , and Iowa -class battleships . By February 1948,
5251-459: The high operating cost of helicopters cost-effective in ensuring that oil platforms continue to operate. Various companies specialize in this type of operation. NASA developed Ingenuity , a 1.8 kg (4.0 lb) helicopter used to survey Mars (along with a rover). It began service in February 2021 and was retired due to sustained rotor blade damage in January 2024 after 73 sorties. As
5340-480: The idea of vertical flight. In July 1754, Russian Mikhail Lomonosov had developed a small coaxial modeled after the Chinese top but powered by a wound-up spring device and demonstrated it to the Russian Academy of Sciences . It was powered by a spring, and was suggested as a method to lift meteorological instruments. In 1783, Christian de Launoy , and his mechanic , Bienvenu, used a coaxial version of
5429-504: The in-service and stored helicopter fleet of 38,570 with civil or government operators was led Robinson Helicopter with 24.7% followed by Airbus Helicopters with 24.4%, then Bell with 20.5 and Leonardo with 8.4%, Russian Helicopters with 7.7%, Sikorsky Aircraft with 7.2%, MD Helicopters with 3.4% and other with 2.2%. The most widespread model is the piston Robinson R44 with 5,600, then the H125/ AS350 with 3,600 units, followed by
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#17327913511985518-662: The lack of an airstrip would make transport via fixed-wing aircraft impossible. The use of transport helicopters to deliver troops as an attack force on an objective is referred to as " air assault ". Unmanned aerial systems (UAS) helicopter systems of varying sizes are developed by companies for military reconnaissance and surveillance duties. Naval forces also use helicopters equipped with dipping sonar for anti-submarine warfare , since they can operate from small ships. Oil companies charter helicopters to move workers and parts quickly to remote drilling sites located at sea or in remote locations. The speed advantage over boats makes
5607-505: The landing gear, and could be optionally fitted with a rescue hoist and an auxiliary external fuel tank. Five of the service-test YR-5As were later converted into dual-control YR-5E s. The United States Navy evaluated three R-5As as the HO2S-1 . Sikorsky soon developed a modified version of the R-5, the S-51 , featuring a greater rotor diameter, greater carrying capacity and gross weight, and
5696-581: The late 1960s. Helicopters have also been used in films, both in front and behind the camera. The largest single non-combat helicopter operation in history was the disaster management operation following the 1986 Chernobyl nuclear disaster . Hundreds of pilots were involved in airdrop and observation missions, making dozens of sorties a day for several months. " Helitack " is the use of helicopters to combat wildland fires . The helicopters are used for aerial firefighting (water bombing) and may be fitted with tanks or carry helibuckets . Helibuckets, such as
5785-555: The limited power did not allow for manned flight. The introduction of the internal combustion engine at the end of the 19th century became the watershed for helicopter development as engines began to be developed and produced that were powerful enough to allow for helicopters able to lift humans. Early helicopter designs utilized custom-built engines or rotary engines designed for airplanes, but these were soon replaced by more powerful automobile engines and radial engines . The single, most-limiting factor of helicopter development during
5874-485: The monorotor design, and coaxial-rotor , tiltrotor and compound helicopters are also all flying today. Four-rotor helicopters ( quadcopters ) were pioneered as early as 1907 in France, and along with other types of multicopters , have been developed mainly for specialized applications such as commercial unmanned aerial vehicles (drones) due to the rapid expansion of drone racing and aerial photography markets in
5963-601: The nearby park, the Parco Forlanini. Emmanuel Dieuaide's steam-powered design featured counter-rotating rotors powered through a hose from a boiler on the ground. In 1887 Parisian inventor, Gustave Trouvé , built and flew a tethered electric model helicopter. In July 1901, the maiden flight of Hermann Ganswindt 's helicopter took place in Berlin-Schöneberg; this was probably the first heavier-than-air motor-driven flight carrying humans. A movie covering
6052-525: The new tri-service system (see 1962 United States Tri-Service aircraft designation system ), many navy and army aircraft were given the low numbers. Under the 1962 system, the low H numbers were given to new aircraft. For example, H-5 was given to the OH-5 , a prototype design which never entered Army service. During its service life, the H-5/HO3S-1 was used for utility, rescue, and mercy missions throughout
6141-812: The next five years conducting ASW tactical operations along the eastern seaboard and in the Caribbean. Leyte departed Quonset Point in January 1959 for the New York Navy Yard where she commenced preinactivation overhaul. She was redesignated AVT-10 and decommissioned both on 15 May 1959, and was assigned to the Philadelphia group of the Atlantic Reserve Fleet , where she remained until sold for scrap in September 1970 and completed in Chesapeake, Virginia . On 4 December 1950,
6230-464: The nose to pitch down, with a resultant increase in airspeed and loss of altitude. Aft cyclic will cause the nose to pitch up, slowing the helicopter and causing it to climb. Increasing collective (power) while maintaining a constant airspeed will induce a climb while decreasing collective will cause a descent. Coordinating these two inputs, down collective plus aft cyclic or up collective plus forward cyclic, will result in airspeed changes while maintaining
6319-429: The pilot. With three passengers, both weights were normally placed in the baggage compartment. However, in conditions of high ambient temperatures, which reduced lift due to the lowered air density, all weights were jettisoned. If the weights could not be recovered later, pilots on future missions were forced to utilize rocks or other improvised weights next to the pilot after offloading three passengers, or else travel at
6408-411: The power normally required to be diverted for the tail rotor to be applied fully to the main rotors, increasing the aircraft's power efficiency and lifting capacity. There are several common configurations that use the counter-rotating effect to benefit the rotorcraft: Tip jet designs let the rotor push itself through the air and avoid generating torque. The number, size and type of engine(s) used on
6497-436: The rotor disk tilts to that side and produces thrust in that direction, causing the helicopter to hover sideways. The collective pitch control or collective is located on the left side of the pilot's seat with a settable friction control to prevent inadvertent movement. The collective changes the pitch angle of all the main rotor blades collectively (i.e. all at the same time) and independently of their position. Therefore, if
6586-406: The rotor in cruise, which allows its rotation to be slowed down , thus increasing the maximum speed of the aircraft. The Lockheed AH-56A Cheyenne diverted up to 90% of its engine power to a pusher propeller during forward flight. There are three basic flight conditions for a helicopter: hover, forward flight and the transition between the two. Hovering is the most challenging part of flying
6675-422: The rotor throughout normal flight. The rotor system, or more simply rotor , is the rotating part of a helicopter that generates lift . A rotor system may be mounted horizontally, as main rotors are, providing lift vertically, or it may be mounted vertically, such as a tail rotor, to provide horizontal thrust to counteract torque from the main rotors. The rotor consists of a mast, hub and rotor blades. The mast
6764-418: The size of the helicopter being designed, so that all but the lightest of helicopter models are powered by turbine engines today. Special jet engines developed to drive the rotor from the rotor tips are referred to as tip jets . Tip jets powered by a remote compressor are referred to as cold tip jets, while those powered by combustion exhaust are referred to as hot tip jets. An example of a cold jet helicopter
6853-483: The skies. Since helicopters can achieve a unique aerial view, they are often used in conjunction with police on the ground to report on suspects' locations and movements. They are often mounted with lighting and heat-sensing equipment for night pursuits. Military forces use attack helicopters to conduct aerial attacks on ground targets. Such helicopters are mounted with missile launchers and miniguns . Transport helicopters are used to ferry troops and supplies where
6942-623: The squadrons based on Leyte were the VF-32 Swordsmen , flying the F4U Corsair . Leyte returned to Norfolk for overhaul on 25 February 1951. After fleet training exercises in the Caribbean terminated on 21 August, the carrier departed for her fifth tour of duty with the United States Sixth Fleet on 3 September. She returned to Norfolk on 21 December for operations out of Hampton Roads , and again steamed for
7031-479: The tail rotor, such as the ducted fan (called Fenestron or FANTAIL ) and NOTAR . NOTAR provides anti-torque similar to the way a wing develops lift through the use of the Coandă effect on the tail boom. The use of two or more horizontal rotors turning in opposite directions is another configuration used to counteract the effects of torque on the aircraft without relying on an anti-torque tail rotor. This allows
7120-448: The throttle is to maintain enough engine power to keep the rotor RPM within allowable limits so that the rotor produces enough lift for flight. In single-engine helicopters, the throttle control is a motorcycle-style twist grip mounted on the collective control, while dual-engine helicopters have a power lever for each engine. A compound helicopter has an additional system for thrust and, typically, small stub fixed wings . This offloads
7209-417: The thrust produced by the tail rotor and causing the nose to yaw in the direction of the applied pedal. The pedals mechanically change the pitch of the tail rotor altering the amount of thrust produced. Helicopter rotors are designed to operate in a narrow range of RPM . The throttle controls the power produced by the engine, which is connected to the rotor by a fixed ratio transmission. The purpose of
7298-428: The time production ceased in 1951, more than 300 examples of all types of the H-5 had been built. The H-5 was originally built by Sikorsky as its model S-48 , designated as the R-5 by the United States Army Air Forces. It was designed to provide a helicopter having greater useful load, endurance, speed, and service ceiling than the Sikorsky R-4 . The R-5 differed from the R-4 by having an increased rotor diameter and
7387-572: The vertical flight he had envisioned. Steam power was popular with other inventors as well. In 1877, the Italian engineer, inventor and aeronautical pioneer Enrico Forlanini developed an unmanned helicopter powered by a steam engine . It rose to a height of 13 meters (43 feet), where it remained for 20 seconds, after a vertical take-off from a park in Milan . Milan has dedicated its city airport to Enrico Forlanini, also named Linate Airport , as well as
7476-531: The world, including flights during Operation Highjump in the Antarctic. While the extra power of the H-5 made it significantly more useful than its R-4 and R-6 cousins, the H-5/HO3S-1 suffered, like most early small tandem-seat single-rotor machines, from center of gravity problems. As a matter of routine, the helicopter was equipped with two iron-bar weights – each in a canvas case – one of 25 lb (11 kg) & one of 50 lb (23 kg). Flying with no passengers, both weights were placed forward alongside
7565-557: Was also developed by Westland as the Westland Widgeon , but the type was never adopted for service. The U.S. Navy ordered four S-51s "off-the-shelf" from Sikorsky in late 1946 for use in the Antarctic and Operation Highjump , placing them into naval inventory as the HO3S-1. Carried aboard the seaplane tender USS Pine Island , on Christmas Day 1946 an HO3S-1 of VX-3 piloted by Lieutenant Commander Walter M. Sessums became
7654-486: Was badly burned. Edison reported that it would take a motor with a ratio of three to four pounds per horsepower produced to be successful, based on his experiments. Ján Bahýľ , a Slovak inventor, adapted the internal combustion engine to power his helicopter model that reached a height of 0.5 meters (1.6 feet) in 1901. On 5 May 1905, his helicopter reached 4 meters (13 feet) in altitude and flew for over 1,500 meters (4,900 feet). In 1908, Edison patented his own design for
7743-511: Was launched on 23 August, sponsored by Alice Dillon Mead, wife of U.S. Senator James M. Mead , and commissioned on 11 April 1946, with Captain Henry F. MacComsey in command. Leyte joined battleship Wisconsin on a good will cruise along the western seaboard of South America in the fall of 1946 before returning to the Caribbean on 18 November to resume shakedown operations. In 1948,
7832-494: Was located just forward of the tail boom and the main stretcher station was located behind the crew cabin. The forward stretcher station could accommodate two casualties, who were accessible to the medic in flight, while the back stretcher station handled only one, not accessible to the medic during the flight. Very little information is known about the operational use of this modification by the USAF, this being abandoned shortly after tests in 1950. The R-5 had been designated under
7921-563: Was the first helicopter ever to be delivered to a commercial operator; on July 29, 1946, the first of three aircraft was handed over to the president of Helicopter Air Transport (HAT) at Sikorsky's plant in Bridgeport, Connecticut . HAT paid a discounted price of $ 48,500 per aircraft and operated them from Camden Central Airport , Camden, in New Jersey, carrying passengers, freight and mail to other local airports. Initially operating on
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