Scramjet programs
In 1986 United States president Ronald Reagan announced the National Aerospace Plane (NASP) program, intended to develop two X-30 aircraft capable of single stage to orbit (SSTO), as well as horizontal takeoff and landing from conventional runways.
As the program proceeded it became clear that Mach 17 was probably the limit, whilst the weight penalty and complexity of the skin heat exchanger and other propulsion systems was going to be substantial.
The program was established by the secretary of defence in 1985, and was funded to the end of FY1994, when the decision was made that the 15 billion dollars required to build the two X-30 test craft were excessive.
At a test facility at Arnold Air Force Base in the U.S. state of Tennessee, the General Applied Science Laboratory (GASL) fired a projectile equipped with a hydrocarbon-powered scramjet engine from a large gun.
Rather than developing and flying a large, expensive spaceplane with orbital capability, Hyper-X flew small test vehicles to demonstrate hydrogen-fueled scramjet engines.
After a free flight where the scramjet operated for about ten seconds the craft made a planned crash into the Pacific Ocean off the coast of southern California.
As for the X-43A Hyper-X, three follow-on projects are now under consideration: X-43B: A scaled-up version of the X-43A, to be powered by the Integrated Systems Test of an Air-Breathing Rocket (ISTAR) engine.
NASA's Marshall Space Propulsion Center has introduced an Integrated Systems Test of the Air-Breathing Rocket (ISTAR) program, prompting Pratt & Whitney, Aerojet, and Rocketdyne to join forces for development.
The US Air Force and Pratt and Whitney have cooperated on the Hypersonic Technology (HyTECH) scramjet engine, which has now been demonstrated in a wind-tunnel environment.
The first surrogate vehicle, SPV1, was launched aboard an unguided Terrier/Improved Orion two-stage solid rocket motor stack from Wallops Island on October 18, 2003, approximately 12 months after program initiation.
This had the exact outer mold line of the eventual shrouded scramjet payload and contained full onboard instrumentation and telemetry suites.
After making slight trajectory corrections to account for launch rail effects, higher than anticipated drag, and actual booster performance, the payload was inserted nominally above 5,200 ft/s (1,600 m/s) and 61,000 ft (19,000 m) altitude.
The results of these two flight tests are summarized in a technical paper AIAA-2005-3297, presented at the 13th International Space Planes and Hypersonics Systems and Technologies Conference (see [3])in Capua, Italy.
After a delay of two months to modify flight hardware based on ground test findings, the first powered vehicle, FFV1, was launched without incident, propelled to speeds of 5,300 ft/s (1,600 m/s) at 63,000 ft (19,000 m) altitude, roughly Mach 5.5.
Further details can be found in the technical paper AIAA-2006-8119,[2] presented at the 14th International Space Planes and Hypersonics Systems and Technologies Conference, in Canberra, Australia.
Alliant Techsystems Inc. (ATK) GASL Division led the contractor team for the FASTT project, developed and integrated the scramjet vehicle, and acted as mission managers for the three flights.
[4] The X-51 is a descendant of earlier efforts including the Advanced Rapid Response Missile Demonstrator and the liquid hydrocarbon-fuelled scramjet engine developed under the USAF's HyTech program.
[7] Another successful test was carried out in mid-March 2022 amid the Russian invasion of Ukraine but further details were kept secret to avoid escalating tensions with Russia only to be leaked by an unnamed Pentagon official in early April.
[8] Follow-on tactical range Hypersonic Attack Cruise Missile (HACM) will be built by Raytheon Technologies and will use a Northrop Grumman scramjet.
The team took a unique approach to the problem of accelerating the engine to the necessary speed by using a Terrier-Orion sounding rocket to take the aircraft up on a parabolic trajectory to an altitude of 314 km.
[5] NASA has partially explained the tremendous difference in cost between the two projects by pointing out that the American vehicle has an engine fully incorporated into an airframe with a full complement of flight control surfaces available.
)[13] The HyShot program currently consists of the following tests: Sponsorship for the HyShot Flight Program was obtained from the University of Queensland, Astrotech Space Operations, Defence Evaluation and Research Agency (DERA (now Qinetiq), UK), National Aeronautics and Space Agency (NASA, USA), Defence, Science and Technology Organisation (DSTO, Australia), Dept.
Hypersonic International Flight Research and Experimentation (HIFiRE) is a joint program of the US Department of Defense and Australian DST Group.
The "purpose of this program is to investigate fundamental hypersonic phenomena and accelerate the development of aerospace vehicle technologies deemed critical to long range precision strike"[14] by using an "affordable, accessible, prototype experimentation strategy".
The notional immediate goal of the study is to produce a hypersonic air-to-surface missile named "Promethee", which would be about 6 metres (20 ft) long and weigh 1,700 kilograms (3,700 lb).
The project includes basic research to gain a better understanding of supersonic fuel mixing and combustion, aerodynamic effects, material sciences and issues in system design.
After NASA's NASP program was cut, American scientists began to look at adopting available Russian technology as a less expensive alternative to developing hypersonic flight.
From 1994 to 1998 NASA worked with the Russian Central Institute of Aviation Motors (CIAM) to test a dual-mode scramjet engine and transfer technology and experience to the West.
According to CIAM telemetry data, the first ignition attempt of the scramjet was unsuccessful, but after 10 seconds the engine was started and the experimental system flew 77s with good performance, up until the planned SA-5 missile self-destruction (according to NASA, no net thrust was achieved).
