High Speed Civil Transport | |
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General information | |
Project for | Supersonic transport |
Issued by | NASA |
History | |
Outcome | Study only |
The High Speed Civil Transport (HSCT) was the focus of the NASA High-Speed Research (HSR) program, which intended to develop the technology needed to design and build a supersonic transport that would be environmentally acceptable and economically feasible. The aircraft was to be a future supersonic passenger aircraft, baselined to cruise at Mach 2.4, or more than twice the speed of sound. The project started in 1990 and ended in 1999. [1]
It was meant to cross the Atlantic or the Pacific Ocean in half the time of a non-supersonic aircraft. It was also intended to be fuel efficient, carry 300 passengers, and allow customers to buy tickets at a price only slightly higher than those of subsonic aircraft. The goal was to provide sufficient technology for an industry-led product launch decision in 2002, and if a product was launched, a maiden flight within 20 years. [2]
The program was based on the successes and failures of the British/French Concorde and the Russian Tupolev Tu-144, as well as a previous NASA Supersonic Transport (SST) program from the early 1970s (for the latter, see Lockheed L-2000 and Boeing 2707.) While the Concorde and Tu-144 programs both yielded production aircraft, neither was produced in sufficient numbers to pay for their development costs.
In 1989, NASA and industry partners began investigating the feasibility of radically higher-speed passenger aircraft. By 1990 the design converged to a Mach 2.4, 300-passenger capable aircraft, and the High-Speed Research program was started. [3] The project was split into two phases which examined a variety of areas for development. The first phase "focused on the development of technology concepts for environmental compatibility". The second phase aimed to demonstrate the environmental technologies and other high-risk technologies for economic viability. [4]
Phase 1 focused on several environmental concerns: NOx emissions which can deplete the ozone layer, community noise, sonic boom noise, and high-altitude radiation. [1] Tests relevant to each concern were carried out. A U-2 spy plane, renamed to the ER-2, was used to measure high-altitude emissions from a Concorde jet and to measure the radiation environment at high altitudes. New engine nozzle technologies were tested to reduce takeoff and landing noise. Sonic boom mitigation technologies were tested using an SR-71 Blackbird, [5] but were considered to be economically unviable; instead, HSCT would be limited to subsonic speeds over land. [6]
Phase 2 demonstrated several key technologies' economic viability. Two F-16XLs were used to test supersonic laminar flow control and to validate advanced CFD design methods. [7] Instead of using the droop nose like that on the Concorde, an "external vision" system would have replaced the cockpit windows entirely with computer-generated graphics made available to the pilots on cockpit displays. Finally, a variety of materials were designed and tested against the very high temperature of Mach 2.4 flight, with titanium and a unique variety of carbon fiber being leading candidates for different areas of the craft. [8] [1] [9]
Though the project was largely successful, it was canceled in 1999 due to budget constraints, [10] as well as Boeing withdrawing interest (i.e. funding) from the project. [11]
Concorde is a retired Anglo-French supersonic airliner jointly developed and manufactured by Sud Aviation and the British Aircraft Corporation (BAC). Studies started in 1954, and France and the UK signed a treaty establishing the development project on 29 November 1962, as the programme cost was estimated at £70 million . Construction of the six prototypes began in February 1965, and the first flight took off from Toulouse on 2 March 1969. The market was predicted for 350 aircraft, and the manufacturers received up to 100 option orders from many major airlines. On 9 October 1975, it received its French Certificate of Airworthiness, and from the UK CAA on 5 December.
Supersonic speed is the speed of an object that exceeds the speed of sound (Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately 343.2 m/s. Speeds greater than five times the speed of sound (Mach 5) are often referred to as hypersonic. Flights during which only some parts of the air surrounding an object, such as the ends of rotor blades, reach supersonic speeds are called transonic. This occurs typically somewhere between Mach 0.8 and Mach 1.2.
The Boeing 2707 was an American supersonic passenger airliner project during the 1960s. After winning a competition for a government-funded contract to build an American supersonic airliner, Boeing began development at its facilities in Seattle, Washington. The design emerged as a large aircraft with seating for 250 to 300 passengers and cruise speeds of approximately Mach 3. It was intended to be much larger and faster than competing supersonic transport (SST) designs such as Concorde.
A sonic boom is a sound associated with shock waves created when an object travels through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding similar to an explosion or a thunderclap to the human ear.
A supersonic transport (SST) or a supersonic airliner is a civilian supersonic aircraft designed to transport passengers at speeds greater than the speed of sound. To date, the only SSTs to see regular service have been Concorde and the Tupolev Tu-144. The last passenger flight of the Tu-144 was in June 1978 and it was last flown in 1999 by NASA. Concorde's last commercial flight was in October 2003, with a November 26, 2003 ferry flight being its last airborne operation. Following the permanent cessation of flying by Concorde, there are no remaining SSTs in commercial service. Several companies have each proposed a supersonic business jet, which may bring supersonic transport back again.
The Lockheed L-2000 was Lockheed Corporation's entry in a government-funded competition to build the United States' first supersonic airliner in the 1960s. The L-2000 lost the contract to the Boeing 2707, but that competing design was ultimately canceled for political, environmental and economic reasons.
Supercruise is sustained supersonic flight of a supersonic aircraft without using afterburner. Many supersonic military aircraft are not capable of supercruise and can maintain Mach 1+ flight only in short bursts with afterburners. Aircraft such as the SR-71 Blackbird are designed to cruise at supersonic speed with afterburners enabled.
The Boeing Sonic Cruiser was a concept jet airliner with a delta wing–canard configuration. It was distinguished from conventional airliners by its delta wing and high-subsonic cruising speed of up to Mach 0.98. Boeing first proposed it in 2001, but airlines generally preferred lower operating costs over higher speed. Boeing ended the Sonic Cruiser project in December 2002 and shifted to the slower but more fuel-efficient 7E7 airliner.
The General Dynamics F-16XL is a derivative of the F-16 Fighting Falcon with a cranked-arrow delta wing. It entered the United States Air Force's (USAF) Enhanced Tactical Fighter (ETF) competition in 1981 but lost to the F-15E Strike Eagle. The two prototypes were shelved until being turned over to NASA for additional aeronautical research in 1988. Both aircraft were fully retired in 2009 and stored at Edwards Air Force Base.
A supersonic aircraft is an aircraft capable of supersonic flight, that is, flying faster than the speed of sound. Supersonic aircraft were developed in the second half of the twentieth century. Supersonic aircraft have been used for research and military purposes, but only two supersonic aircraft, the Tupolev Tu-144 and the Concorde, ever entered service for civil use as airliners. Fighter jets are the most common example of supersonic aircraft.
A supersonic business jet (SSBJ) is a business jet travelling above the speed of sound: a supersonic aircraft. Some manufacturers are designing or have been designing SSBJs, but none are currently available. Usually intended to transport about ten passengers, proposed SSBJs would be about the same size as subsonic business jets.
Quiet Spike was a collaborative program between Gulfstream Aerospace and NASA's Dryden Flight Research Center to investigate the suppression of sonic booms. The patent was published with the United States Patent and Trademark Office in 2004 and is owned by Gulfstream Aerospace.
The Avion de Transport Supersonique Futur (ATSF) also known as Alliance, was a concept design for supersonic transport that was being worked on by both British Aerospace and Aérospatiale. The aircraft was to be based on the experience learned from the supersonic Concorde, and was to fly at a top speed of roughly Mach 2. Preliminary designs were produced, with some wind-tunnel testing of small-scale models, but development apparently stalled in the early 2000s.
The Next Generation Supersonic Transport is a supersonic transport (SST) being developed by the Japanese Space Agency JAXA. By comparison to the Concorde this new design will carry three times as many passengers and fly roughly at the same speed 1,522.4 mph (2,450.1 km/h). It also has twice the range. The goal is to achieve a ticket price comparable to that of commercial business class. JAXA had expected to launch the plane by 2015. An 11.5-meter prototype was tested on October 10, 2005.
The Gulfstream X-54 is a proposed research and demonstration aircraft, under development in the United States by Gulfstream Aerospace for NASA, that is planned for use in sonic boom and supersonic transport research.
The Anti-Concorde Project, founded by environmental activist Richard Wiggs, challenged the idea of supersonic passenger transport, and curtailed Concorde's commercial prospects. When Concorde entered service in 1976, of the 74 options held at the time of the first flight, only those for the state airlines of Britain (BOAC) and France were taken up, so that only 20 were built, although flights were also flown for Braniff International and Singapore Airlines. It triggered research into the factors affecting the creation of sonic booms, which led to the Shaped Sonic Boom Demonstration which achieved their goal of reducing the intensity of sonic booms, and echoed public concern about aircraft noise that resulted in more restrictive noise limits for aircraft and airport operations, as well as changes in both operating procedures and aircraft design to further reduce noise levels.
The Zero Emission Hyper Sonic Transport or ZEHST is a planned hypersonic passenger jet airliner project by the multinational aerospace conglomerate EADS and the Japanese national space agency JAXA.
The SonicStar was a proposed high-supersonic aircraft business jet designed by SonicStar SAS led by Bernard Rousset and motorized by HyperMach.
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