75-638: The Sikorsky S-92 is an American twin-engine medium-lift helicopter built by Sikorsky Aircraft for the civil and military helicopter markets. The S-92 was developed from the Sikorsky S-70 helicopter and has similar parts such as flight control and rotor systems. The H-92 Superhawk is a military version of the S-92 in the utility transport role, capable of carrying 22 troops. The H-92 can also be configured for specific missions, including search and rescue and executive transportation. The CH-148 Cyclone
150-575: A Eurocopter EC225 Super Puma contracted by Statoil , that company announced that it would not use that type again and instead use the Sikorsky S-92 to meet its needs, stipulating that operators it contracts with, such as CHC Helikopter Service , will be required to use such equipment. The S-92A is the civilian variant and is available in a number of versions. The civil transport version has an airliner-type interior that seats 19 passengers. The utility transport version has 22 side-facing seats with
225-444: 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
300-417: 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
375-465: A full cabin width rear ramp. The 733 sq ft (68.1 m) interior cabin area can also be configured to accommodate up to three airline-style LD3 cargo containers. Additional stowage space is available in the 140 sq ft (13 m) area located in the aft ramp compartment. During development it was referred to as the S-92C Helibus. The H-92 Superhawk is the military variant of
450-463: 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
525-405: 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
600-510: 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,
675-416: 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
750-740: A joint-venture with Tata Advanced Systems for S-92 manufacturing in India for export and domestic markets. A US$ 200 million manufacturing plant will be operational in Hyderabad by 2010. Initially, TASL will supply the complete cabins for the S-92 to Sikorsky. The first cabin was delivered in November 2010. The S-92 is multi-purpose helicopter powered by twin GE CT7-8A turboshaft engines and has an aluminum airframe and some composite components. The four-bladed fully articulated composite main rotor blade
825-514: A key requirement of the Nordic Standard Helicopter Program (NSHP) for shipboard stowage. The lengthening of the fuselage and shortening of the tail pylon shifted the aircraft center of gravity (CG) forward, permitting a more level attitude in flight. The longer fuselage allowed for an additional row of three seats, as well as a larger passenger door option for Search and Rescue (SAR) customers. Sikorsky incorporated
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#1732780975875900-503: A need for aircraft such as the S-92 with sufficient capability. Sikorsky Aircraft first displayed a S-92 mockup of the planned helicopter in 1992. The S-92 was to be offered for sale beginning in 1993, but due to a decline in the international market for helicopters, this was delayed. In 1995 Sikorsky formed Team S-92 with international partners and launched the helicopter program at the Paris Airshow that year. Sikorsky developed
975-477: 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
1050-494: 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
1125-441: 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
1200-417: 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
1275-429: 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
1350-624: Is a shipboard maritime helicopter variant developed for the Royal Canadian Air Force to support naval operations of the Royal Canadian Navy . The Sikorsky VH-92 is a variant under development to replace the United States Marine Corps ' Marine One U.S. Presidential transport fleet. After the 1973 oil crisis , major oil and gas companies began exploration further offshore, thus creating
1425-452: 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
1500-452: 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
1575-547: 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
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#17327809758751650-678: 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
1725-411: 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
1800-556: Is wider and has a longer radius than the Sikorsky S-70. The tapered blade tip sweeps back and angles downward to reduce noise and increase lift. Most of the rotor system components aside from the blades are titanium. The S-92 features an active vibration control system, using vibration sensors and structurally mounted force generators to increase flight comfort and lower acoustic levels to below certification requirements. A 2008 study by Norway's Flymedisinsk Institute found that
1875-572: 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
1950-588: 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
2025-520: The CH-148 Cyclone . Canada ordered 28 helicopters in November 2004. The program has been delayed multiple times. As of November 2019, nineteen CH-148 Cyclones have been built, delivered, and accepted by the government of Canada. The Canadian military declared initial operational capacity in June 2018, and expects full operational capacity by 2022. The S-92A variant, designated VH-92 will be used as
2100-527: 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
2175-499: 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
2250-558: 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
2325-762: 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
Sikorsky S-92 - Misplaced Pages Continue
2400-478: 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
2475-453: 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
2550-571: 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,
2625-640: The S-92 to compete with civil aircraft such as the Aerospatiale/Eurocopter Super Puma . The helicopter uses a new airframe with dynamic components based on the S-70/H-60 components. The S-92 took its maiden flight on December 23, 1998 at the Sikorsky Development Flight Center, West Palm Beach, Florida. In July 2000, Sikorsky announced design changes to the S-92. The fuselage of prototype #3
2700-606: The S-92's vibration levels were 42 percent above that of the Eurocopter EC225 Super Puma ; Sikorsky disputed this finding, saying that the study hadn't used their latest anti-vibration technology. In February 2011, as published on a Norwegian newspaper's website, the noise and vibration levels were reportedly subject to health concerns, allegedly causing tinnitus and heart problems. A number of safety features such as flaw tolerance, bird strike capability, and engine burst containment have been incorporated into
2775-522: The S-92. It has been demonstrated to the U.S. Air Force, Marine Corps and Coast Guard. The H-92 has more powerful GE CT7-8C engines, rated at 3,070 shp (2,290 kW) and, unlike the S-92, has fly-by-wire flight controls. The search and rescue variant provides space for seats, litters , auxiliary fuel cell and SAR emergency equipment. In July 2004, the H-92 Superhawk was selected by Canada for its Maritime Helicopter Programme (MHP) as
2850-550: 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
2925-466: 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
3000-435: 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
3075-677: 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
Sikorsky S-92 - Misplaced Pages Continue
3150-624: The changes into the following two prototypes as the production standard configuration. Some reports suggested that the modifications were actually to resolve damage from structural design flaws. The S-92 is built and customized in Sikorsky's Coatesville, Pennsylvania facility. The S-92 received Federal Aviation Administration (FAA) part 29 type certification on December 19, 2002, and received International European Aviation Safety Agency /Joint Aviation Authorities (EASA/JAA) certification on June 8, 2004. In June 2009, Sikorsky Aircraft entered into
3225-406: 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,
3300-797: 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 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
3375-470: 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
3450-675: The design. Adherence to FAA FAR part 29 has led the FAA certification board to call the S-92 the "safest helicopter in the world". The S-92 was not able to meet the Federal Aviation Regulation "run dry" specification for loss of oil pressure in the main gearbox, but was certified with an exemption due to the unlikelihood of such a situation occurring; this was a factor in the fatal crash of Cougar Helicopters Flight 91 in 2009. The S-92 received FAA certification in 2002, and International certification in June 2004. The first S-92
3525-439: 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
3600-486: 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
3675-574: 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 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,
3750-515: 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
3825-480: 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
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#17327809758753900-504: 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
3975-662: 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
4050-581: 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
4125-555: 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
4200-601: 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
4275-434: The next Marine One to fly the U.S. President. Data from Sikorsky S-92 specifications, International Directory of Civil Aircraft General characteristics Performance Related development Aircraft of comparable role, configuration, and era Related lists Helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors . This allows
4350-464: 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
4425-411: 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
4500-847: The preferred supplier status of NHIndustries NH90 for the Nordic Standard Helicopter Programme an open competition was held. Sikorsky entered the S-92 as a candidate for the Norwegian All Weather Search and Rescue Helicopter (NAWSARH) that is planned to replace the Royal Norwegian Air Force Westland Sea King Mk.43B in 2015. The other candidates for the NAWSARH contract of 10 to 12 helicopters were AgustaWestland AW101 , Bell Boeing V-22 Osprey , Eurocopter EC225 , and NHIndustries NH90 . The V-22
4575-467: The preferred supplier, will not be used due to irregularities with its bid. The UK government subsequently opted for a smaller £2.5bn contract with the Bristow Group to operate 11 S-92s (and 11 AW189s) from 10 bases. The Irish Coast Guard replaced its Sikorsky S-61N fleet with the S-92, beginning in 2012. The aircraft are operated by CHC Helicopter . In the wake of the deadly 2016 crash of
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#17327809758754650-612: The rapid expansion of drone racing and aerial photography markets in 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
4725-436: 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
4800-406: 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
4875-422: 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
4950-418: 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
5025-483: 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
5100-479: 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
5175-448: 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
5250-417: 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
5325-572: 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
5400-486: 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
5475-611: Was delivered in late 2004 to launch customer PHI, Inc . Sikorsky entered a Search and rescue variant of the H-92 in U.S. Air Force 's CSAR-X combat search and rescue competition beginning in 2006. Its competitors were the AgustaWestland EH101 and HH-47 , but by December 2012 all other manufacturers had withdrawn. Flight International magazine expects Sikorsky to bid a version of its MH-60 special operations helicopter. After Sikorsky successfully challenged in court
5550-684: Was eliminated from the competition in 2012. The S-92 was removed from the competition in July 2013 and was subsequently won by AgustaWestland with an order for 16 AW101s. The S-92 competed with the Eurocopter EC225 for the UK Search and Rescue – Helicopter (SAR-H) program. In February 2010, the S-92 was selected by the UK in a £6bn deal to replace 40 Sea King search and rescue helicopters with 25 to 30 S-92s; it subsequently announced that Soteria,
5625-401: Was lengthened by 16 in (40 cm) aft of the cockpit, the tail pylon was shortened by 41 in (1.04 m), and the horizontal stabilizer was repositioned from the left side opposite the tail rotor to the right side at the base of the tail pylon. The modifications to the tail solved a pitch stability issue discovered during flight testing, and were reported to allow the aircraft to meet
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