摘要 :
This paper presents the status of the airbreathing hypersonic airplane and space-access, vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the s...
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This paper presents the status of the airbreathing hypersonic airplane and space-access, vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for low-speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission flexibility restraints.
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摘要 :
This paper presents the status of the airbreathing hypersonic airplane and space-access, vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the s...
展开
This paper presents the status of the airbreathing hypersonic airplane and space-access, vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for low-speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission flexibility restraints.
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The General Atomics RQ-1A Predator has become an essential tool for battlefield commanders. However, its low maximum speed and poor performance in rain and icing conditions limit its usefulness. In the spring of 1999 two 10-studen...
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The General Atomics RQ-1A Predator has become an essential tool for battlefield commanders. However, its low maximum speed and poor performance in rain and icing conditions limit its usefulness. In the spring of 1999 two 10-student sections of the aircraft design class at the United States Air Force Academy studied ways to improve Predator's usefulness. They determined that small turbine engines, electro-expulsive deicing systems, and several simple aerodynamic refinements would significantly improve Predator's capabilities. These results and the methods used to generate them are described.
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摘要 :
The General Atomics RQ-1A Predator has become an essential tool for battlefield commanders. However, its low maximum speed and poor performance in rain and icing conditions limit its usefulness. In the spring of 1999 two 10-studen...
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The General Atomics RQ-1A Predator has become an essential tool for battlefield commanders. However, its low maximum speed and poor performance in rain and icing conditions limit its usefulness. In the spring of 1999 two 10-student sections of the aircraft design class at the United States Air Force Academy studied ways to improve Predator's usefulness. They determined that small turbine engines, electro-expulsive deicing systems, and several simple aerodynamic refinements would significantly improve Predator's capabilities. These results and the methods used to generate them are described.
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摘要 :
A hybrid-electric propulsion system combines the advantages of fuel-based systems and battery powered systems and offers new design freedom. To take full advantage of this technology, aircraft designers must be aware of its key di...
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A hybrid-electric propulsion system combines the advantages of fuel-based systems and battery powered systems and offers new design freedom. To take full advantage of this technology, aircraft designers must be aware of its key differences, compared to conventional, carbon-fuel based, propulsion systems. This paper gives an overview of the challenges and potential benefits associated with the design of aircraft that use hybrid-electric propulsion systems. It offers an introduction of the most popular hybrid-electric propulsion architectures and critically assess them against the conventional and fully electric propulsion configurations. The effects on operational aspects and design aspects are covered. Special consideration is given to the application of hybrid-electric propulsion technology to both unmanned and vertical take-off and landing aircraft. The authors conclude that electric propulsion technology has the potential to revolutionize aircraft design. However, new and innovative methods must be researched, to realize the full benefit of the technology.
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摘要 :
A hybrid-electric propulsion system combines the advantages of fuel-based systems and battery powered systems and offers new design freedom. To take full advantage of this technology, aircraft designers must be aware of its key di...
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A hybrid-electric propulsion system combines the advantages of fuel-based systems and battery powered systems and offers new design freedom. To take full advantage of this technology, aircraft designers must be aware of its key differences, compared to conventional, carbon-fuel based, propulsion systems. This paper gives an overview of the challenges and potential benefits associated with the design of aircraft that use hybrid-electric propulsion systems. It offers an introduction of the most popular hybrid-electric propulsion architectures and critically assess them against the conventional and fully electric propulsion configurations. The effects on operational aspects and design aspects are covered. Special consideration is given to the application of hybrid-electric propulsion technology to both unmanned and vertical take-off and landing aircraft. The authors conclude that electric propulsion technology has the potential to revolutionize aircraft design. However, new and innovative methods must be researched, to realize the full benefit of the technology.
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The first powered vertical flight was accomplished less than four years after the first powered horizontal flight was made by the Wright Brothers. But it was not until nearly 30 years later that the first practical vertical take-o...
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The first powered vertical flight was accomplished less than four years after the first powered horizontal flight was made by the Wright Brothers. But it was not until nearly 30 years later that the first practical vertical take-off and landing aircraft was flown. By World War II, the problem of achieving practical vertical flight had been solved with the introduction of the helicopter, but higher speeds were desired. Vertical and/or Short Take-Off and Landing (V/STOL) aircraft air intended to combine the vertical take-off and landing capability of the helicopter with the high forward speed of an airplane. The key problems with developing a practical vertical take-off and landing aircraft have been the same as with the early fixed-wing aircraft: high thrust to weight and adequate controllability. This paper looks at the key achievements in vertical flight throughout the 20th century.
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摘要 :
The first powered vertical flight was accomplished less than four years after the first powered horizontal flight was made by the Wright Brothers. But it was not until nearly 30 years later that the first practical vertical take-o...
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The first powered vertical flight was accomplished less than four years after the first powered horizontal flight was made by the Wright Brothers. But it was not until nearly 30 years later that the first practical vertical take-off and landing aircraft was flown. By World War II, the problem of achieving practical vertical flight had been solved with the introduction of the helicopter, but higher speeds were desired. Vertical and/or Short Take-Off and Landing (V/STOL) aircraft air intended to combine the vertical take-off and landing capability of the helicopter with the high forward speed of an airplane. The key problems with developing a practical vertical take-off and landing aircraft have been the same as with the early fixed-wing aircraft: high thrust to weight and adequate controllability. This paper looks at the key achievements in vertical flight throughout the 20th century.
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The Convair/Navy XFY-1 VTOL fighter was ahead of its time. In the early 1950s it became the first airplane to take off vertically, hover, transition to high speed level flight, transition back to hover, and land vertically. Pilot ...
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The Convair/Navy XFY-1 VTOL fighter was ahead of its time. In the early 1950s it became the first airplane to take off vertically, hover, transition to high speed level flight, transition back to hover, and land vertically. Pilot "Skeets" Coleman made a number of successful flights at Moffett Field South of San Francisco, at Brown Field near the California/Mexican border, and at San Diego's Lindbergh Field. This "first of a kind" aircraft soon adopted the name "POGO". The POGO with its stall proof delta wing had near perfect aerodynamic characteristics in hover, transition and level flight. There were no "black boxes" needed for stability augmentation. The POGO was one of the very first aircraft to use hydraulic power flight controls - a system used today on all modern fighter and transport aircraft. To accommodate both vertical and horizontal flight, the pilot's seat rotated to align the pilot with his engine controls, his control stick and rudder pedals, and to provide the best possible pilot vision. As it turned out, the pilot's over the shoulder vision for judging altitude, sink rate and roll rate during hover descent to touchdown was not the best.
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摘要 :
The Convair/Navy XFY-1 VTOL fighter was ahead of its time. In the early 1950s it became the first airplane to take off vertically, hover, transition to high speed level flight, transition back to hover, and land vertically. Pilot ...
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The Convair/Navy XFY-1 VTOL fighter was ahead of its time. In the early 1950s it became the first airplane to take off vertically, hover, transition to high speed level flight, transition back to hover, and land vertically. Pilot "Skeets" Coleman made a number of successful flights at Moffett Field South of San Francisco, at Brown Field near the California/Mexican border, and at San Diego's Lindbergh Field. This "first of a kind" aircraft soon adopted the name "POGO". The POGO with its stall proof delta wing had near perfect aerodynamic characteristics in hover, transition and level flight. There were no "black boxes" needed for stability augmentation. The POGO was one of the very first aircraft to use hydraulic power flight controls - a system used today on all modern fighter and transport aircraft. To accommodate both vertical and horizontal flight, the pilot's seat rotated to align the pilot with his engine controls, his control stick and rudder pedals, and to provide the best possible pilot vision. As it turned out, the pilot's over the shoulder vision for judging altitude, sink rate and roll rate during hover descent to touchdown was not the best.
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