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33-501: The 11 t (24,000 lb) MTOW , pressurised aircraft should seat 19 to 22 passengers, reach up to 330 kn (610 km/h) over a range of 500 nmi (930 km). Initial requirements targeted lower costs than conventional rotorcraft . The engines stay in a fixed position while the proprotors swivels independently, powered by a split gearbox. During 1998, the European helicopter manufacturer AgustaWestland partnered with

66-423: A 17% drag reduction, a 7% to 20% noise reduction, and a 250 nmi (460 km) radius flown in 1 hour 45 minutes, hover included. By 2021, AgustaWestland intends to achieve comparable manufacturing and operating costs to those of conventional helicopters . The wings will be made out of epoxy carbon fiber , their 12 m (39 ft) wingspan is broadly similar to that of the preceding AW609 tiltrotor, while

99-617: A decrease in lift on the wing due to an altered airfoil shape, and the increase in weight from the ice load will usually result having to fly at a greater angle of attack to compensate for lost lift to maintain altitude. This increases fuel consumption and further reduces speed, making a stall more likely to occur, causing the aircraft to lose altitude. Ice accumulates on helicopter rotor blades and aircraft propellers causing weight and aerodynamic imbalances that are amplified due to their rotation. Anti-ice systems installed on jet engines or turboprops help prevent airflow problems and avert

132-532: A percussive force initiated by actuators inside the structure which induce a shock wave in the surface to be cleared. Hybrid systems have also been developed that combine the EMEDS with heating elements, where a heater prevents ice accumulation on the leading edge of the airfoil and the EMED system removes accumulations aft of the heated portion of the airfoil. Passive systems employ icephobic surfaces. Icephobicity

165-471: A substantial loss of climb performance with particularly critical consequences if an engine were to fail. This latter concern has resulted in bleed air systems being uncommon in small turbine aircraft, although they have been successfully implemented on some small aircraft such as the Cessna CitationJet . Electro-thermal systems use heating coils (much like a low output stove element) buried in

198-589: Is "bled" off one or more engines' compressor sections into tubes routed through wings, tail surfaces, and engine inlets. Spent air is exhausted through holes in the wings' undersides. A disadvantage of these systems is that supplying an adequate amount of bleed air can negatively affect engine performance. Higher-than-normal power settings are often required during cruise or descent, particularly with one or more inoperative engines. More significantly, use of bleed air affects engine temperature limits and often necessitates reduced power settings during climb, which may cause

231-775: Is considered a permanent modification. Alternatively, holders of an Air Operator Certificate (AOC) may vary the Maximum Declared Take-Off Weight (MDTOW) for their aircraft. They can subscribe to a scheme, and then vary the weight for each aircraft without further charge. An aircraft can have its MTOW increased by reinforcement due to additional or stronger materials. For example, the Airbus A330 242 tonnes MTOW variant / A330neo uses Scandium–aluminium (scalmalloy) to avoid an empty weight increase. In many circumstances an aircraft may not be permitted to take off at its MTOW. In these circumstances

264-509: Is the lowest of the: Ice protection In aeronautics , ice protection systems keep atmospheric moisture from accumulating on aircraft surfaces, such as wings, propellers , rotor blades , engine intakes , and environmental control intakes. Ice buildup can change the shape of airfoils and flight control surfaces , degrading control and handling characteristics as well as performance. An anti-icing, de-icing , or ice protection system either prevents formation of ice , or enables

297-575: The Saab 340 and Embraer EMB 120 Brasilia . Pneumatic de-Icing boots are sometimes found on other types, especially older aircraft. These are rarely used on modern jet aircraft. It was invented by B.F. Goodrich in 1923. Sometimes called a weeping wing, running wet, or evaporative system, these systems use a deicing fluid—typically based on ethylene glycol or isopropyl alcohol to prevent ice forming and to break up accumulated ice on critical surfaces of an aircraft. One or two electrically-driven pumps send

330-463: The chord is roughly doubled to 1.9 m (6 ft 3 in). Each wing has two control surfaces : flaperons for lift and control, and another lowered during vertical take offs , to reduce the exposed wing area to the propeller flow. While compact, the wing's structure features a highly integrated wingbox of composite construction, permitting the large movable surfaces over half the wing chord. The NGCTR's proprotors and wingtips are movable while

363-461: The maximum structural takeoff weight or maximum structural takeoff mass , is the maximum weight at which the pilot is allowed to attempt to take off , due to structural or other limits. The analogous term for rockets is gross lift-off mass , or GLOW . MTOW is usually specified in units of kilograms or pounds. MTOW is the heaviest weight at which the aircraft has been shown to meet all the airworthiness requirements applicable to it. It refers to

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396-781: The American aerospace company Bell Helicopters to develop a production tiltrotor based on the earlier experimental Bell XV-15 . The resulting AgustaWestland AW609 is the first civilian tiltrotor. In 2000, AgustaWestland began studies for the Next-Generation Civil Tiltrotor (NGCTR), twice the size of the AW609. In August 2014, the European Union launched its CleanSky 2 research initiative, to award contracts advancing aerospace technology. AgustaWestland received $ 328 million through this programme towards

429-522: The NGCTR, then in the detailed design study phase, while 60% of the funding was passed on to partners in the project, along with the Airbus RACER compound helicopter. By October 2014, the maiden flight was targeted for 2020. New prop-rotor designs, new wing geometries, optimized engine configurations, lean manufacturing, low carbon footprint and other applicable technologies were evaluated. By 2017,

462-401: The aircraft structure is capable of withstanding all the loads likely to be imposed on it during the takeoff, and occasionally by the maximum flight weight . It is possible to have an aircraft certified with a reduced MTOW, lower than the structural maximum, to take advantage of lower MTOW-based fees, such as insurance premiums, landing fees and air traffic control fees are MTOW based. This

495-430: The aircraft to shed the ice before it becomes dangerous. Aircraft icing increases weight and drag, decreases lift, and can decrease thrust. Ice reduces engine power by blocking air intakes. When ice builds up by freezing upon impact or freezing as runoff, it changes the aerodynamics of the surface by modifying the shape and the smoothness of the surface which increases drag, and decreases wing lift or propeller thrust. Both

528-429: The airframe structure to generate heat when a current is applied. The heat can be generated continuously, or intermittently. The Boeing 787 Dreamliner uses electro-thermal ice protection. In this case the heating coils are embedded within the composite wing structure. Boeing claims the system uses half the energy of engine fed bleed-air systems, and reduces drag and noise. Etched foil heating coils can be bonded to

561-437: The electric heater to provide sufficient heat to prevent the formation of ice on the windscreen. However, windscreen electric heaters may only be used in flight, as they can overheat the windscreen. They can also cause compass deviation errors by as much as 40°. One proposal used carbon nanotubes formed into thin filaments which are spun into a 10 micron-thick film. The film is a poor electrical conductor, due to gaps between

594-535: The engines are static, unlike earlier tiltrotors, for better aerodynamic efficiency. Power is delivered from the engines to the swiveling proprotor assemblies through a split gearbox. Each composite rotorblades include a heat-generating layer for ice protection . Data from Flightglobal General characteristics Related development Related lists MTOW The maximum takeoff weight ( MTOW ) or maximum gross takeoff weight ( MGTOW ) or maximum takeoff mass ( MTOM ) of an aircraft , also known as

627-502: The first flight had been pushed back to 2023. During September 2017, an Italian Aerospace Research Centre -led consortium was selected to design and produce the NGCTR's wing. In 2018, Leonardo defined the rotorcraft's structural requirements with a preliminary design review released on 26 November, before a critical design review in 2019, the prototype's wing assembly in 2020. The preliminary design review started in December 2018 and

660-410: The fluid to proportioning units that divide the flow between areas to be protected. A second pump is used for redundancy, especially for aircraft certified for flight into known icing conditions , with additional mechanical pumps for the windshield. Fluid is forced through holes in panels on the leading edges of the wings, horizontal stabilizers, fairings, struts, engine inlets, and from a slinger-ring on

693-424: The inside of metal aircraft skins to lower power use compared to embedded circuits as they operate at higher power densities. For general aviation , ThermaWing uses a flexible, electrically conductive, graphite foil attached to a wing's leading edge. Electric heaters heat the foil which melts ice. Small wires or other conductive materials can be embedded in the windscreen to heat the windscreen. Pilots can turn on

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726-399: The long direction of the boot. It is typically placed on the leading edge of an aircraft's wings and stabilizers. The chambers are rapidly inflated and deflated, either simultaneously, or in a pattern of specific chambers only. The rapid change in shape of the boot is designed to break the adhesive force between the ice and the rubber, and allow the ice to be carried away by the air flowing past

759-418: The maximum permissible aircraft weight at the start of the takeoff run. MTOW of an aircraft is fixed and does not vary with altitude, air temperature, or the length of the runway to be used for takeoff or landing. Maximum permissible takeoff weight or "regulated takeoff weight", varies according to flap setting, altitude, air temperature, length of runway and other factors. It is different from one takeoff to

792-437: The maximum weight permitted for takeoff will be determined taking account of the following: The maximum weight at which a takeoff may be attempted, taking into account the above factors, is called the maximum permissible takeoff weight, maximum allowed takeoff weight or regulated takeoff weight. The Field Limited Weight is the lowest of the: The Runway Limited Weight is the lowest of the: The Regulated Take-Off Weight

825-434: The minuscule holes; this made the systems popular in older business jets . Disadvantages are greater maintenance requirements than pneumatic boots, the weight of potentially unneeded fluid aboard the aircraft, the finite supply of fluid when it is needed, and the unpredictable need to refill the fluid, which complicates en route stops. Bleed air systems are used by most large aircraft with jet engines or turboprops. Hot air

858-494: The nanotubes. Instead, current causes a rapid rise in temperature, heating up twice as fast as nichrome , the heating element of choice for in-flight de-icing, while using half the energy at one ten-thousandth the weight. Sufficient material to cover the wings of a 747 weighs 80 g (2.8 oz) and costs roughly 1% of nichrome. Aerogel heaters have also been suggested, which could be left on continuously at low power. Electro-mechanical Expulsion Deicing Systems (EMEDS) use

891-483: The next, but can never be higher than the MTOW. Certification standards applicable to the airworthiness of an aircraft contain many requirements. Some of these requirements can only be met by specifying a maximum weight for the aircraft, and demonstrating that the aircraft can meet the requirement at all weights up to, and including, the specified maximum. This limit is typically driven by structural requirements – to ensure

924-576: The propeller and the windshield sprayer. These panels have 1 ⁄ 400 inch (0.064 mm) diameter holes drilled in them, with 800 holes per square inch (120/cm ). The system is self cleaning, and the fluid helps clean the aircraft, before it is blown away by the slipstream. The system was initially used during World War II by the British , having been developed by Tecalemit-Kilfrost-Sheepbridge Stokes (TKS) . Advantages of fluid systems are mechanical simplicity and minimal airflow disruption from

957-408: The risk of serious internal engine damage from ingested ice. These concerns are most acute with turboprops, which more often have sharp turns in the intake path where ice tends to accumulate. The pneumatic boot is usually made of layers of rubber or other elastomers , with one or more air chambers between the layers. If multiple chambers are used, they are typically shaped as stripes aligned with

990-412: The wing. However, the ice must fall away cleanly from the trailing sections of the surface, or it could re-freeze behind the protected area. Re-freezing of ice in this manner was a contributing factor to the crash of American Eagle Flight 4184 . Older pneumatic boots were thought to be subject to ice bridging. Slush could be pushed out of reach of the inflatable sections of the boot before hardening. This

1023-595: Was planned for 2024. The preliminary design concept, aimed at the deepwater drilling energy market, was of a pressurized aircraft with an 11 t (24,000 lb) MTOW to seat 19 to 22 passengers, reach up to 330 kn (610 km/h) over a range of 500 nmi (930 km) and up to a ceiling of 25,000 ft (7,600 m). The initial requirements targeted direct operating costs that were 30% below those of conventional rotorcraft, while recurring costs were 50% below. The CleanSky 2 performance objectives for 2020, compared to contemporary aircraft from 2000, were

Leonardo Next-Generation Civil Tiltrotor - Misplaced Pages Continue

1056-446: Was resolved by speeding up the inflation/deflation cycle, and by alternating the timing of adjacent cells. Testing and case studies performed in the 1990s have demonstrated that ice bridging is not a significant concern with modern boot designs. Pneumatic boots are appropriate for low and medium speed aircraft, without leading edge lift devices such as slats , so this system is most commonly found on smaller turboprop aircraft such as

1089-680: Was scheduled to be completed by the first quarter of 2019, while the critical design review was pushed back to 2020 and prototype construction was then planned between 2021 and 2022. In early 2019, Leonardo selected the General Electric CT7 turboshaft to power the NGCTR demonstrator. The wing was tested in a windtunnel for a second phase in early 2021. By May 2021, major components of the demonstrator were under production by Leonardo and its partners ahead of final assembly. Certification must comply with EASA CS-25 for large airplanes and CS-29 for large rotorcraft. By 2023, first flight

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