NASA's B-52B aircraft over the Dryden Flight Research Center after the successful launch of the second X-43A hypersonic research vehicle.

NASA's B-52B launch aircraft at sunset with the second X-43A hypersonic research vehicle attached to a modified Pegasus rocket under its right wing.

The second X-43A hypersonic research vehicle, mounted under the right wing of the B-52B launch aircraft, viewed from the B-52 cockpit. The crew is working on closing out the research vehicle, preparing it for flight.

An artist's rendering of the air-breathing, hypersonic X-43B, the third and largest of NASA's Hyper-X series flight demonstrators, which could fly later this decade. Revolutionizing the way we gain access to space is NASA's primary goal for the Hypersonic Investment Area, managed for NASA by the Advanced Space Transportation Program at the Marshall Space Flight Center in Huntsville, Alabama. The Hypersonic Investment area, which includes leading-edge partners in industry and academia, will support future generation reusable vehicles and improved access to space. These technology demonstrators, intended for flight testing by decade's end, are expected to yield a new generation of vehicles that routinely fly about 100,000 feet above Earth's surface and reach sustained speeds in excess of Mach 5 (3,750 mph), the point at which "supersonic" flight becomes "hypersonic" flight. The flight demonstrators, the Hyper-X series, will be powered by air-breathing rocket or turbine-based engines, and ram/scramjets. Air-breathing engines, known as combined-cycle systems, achieve their efficiency gains over rocket systems by getting their oxygen for combustion from the atmosphere, as opposed to a rocket that must carry its oxygen. Once a hypersonic vehicle has accelerated to more than twice the speed of sound, the turbine or rockets are turned off, and the engine relies solely on oxygen in the atmosphere to burn fuel. When the vehicle has accelerated to more than 10 to 15 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's series of hypersonic flight demonstrators includes three air-breathing vehicles: the X-43A, X-43B and X-43C.

An inert AIM-54 Phoenix missile nestled under the fuselage of NASA Dryden's F-15B aircraft is being studied as a possible test vehicle to obtain hypersonic data.

All-Body Hypersonic Vehicle: Experimental Shadowgraph

Artwork Artist conception of a hypersonic futuristic space vehicle re-entry

Jonathan Lopez works on a hypersonic Fiber Optic Sensing System at NASA’s Armstrong Flight Research Center in Edwards, California, on Feb. 13, 2025. The system measures strain and temperature, critical safety data for hypersonic vehicles that travel five time the speed of sound.

Jonathan Lopez and Allen Parker confer on the hypersonic Fiber Optic Sensor System at NASA’s Armstrong Flight Research Center in Edwards, California, on February 13, 2025. The system measures strain and temperature, critical safety data for hypersonic vehicles that travel five time the speed of sound.

The second X-43A hypersonic research aircraft, attached to a modified Pegasus booster rocket and followed by a chase F-18, was taken to launch altitude by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. In a combined research effort involving Dryden, Langley, and several industry partners, NASA demonstrated the value of its X-43A hypersonic research aircraft, as it became the first air-breathing, unpiloted, scramjet-powered plane to fly freely by itself. The March 27 flight, originating from NASA's Dryden Flight Research Center, began with the Agency's B-52B launch aircraft carrying the X-43A out to the test range over the Pacific Ocean off the California coast. The X-43A was boosted up to its test altitude of about 95,000 feet, where it separated from its modified Pegasus booster and flew freely under its own power. Two very significant aviation milestones occurred during this test flight: first, controlled accelerating flight at Mach 7 under scramjet power, and second, the successful stage separation at high dynamic pressure of two non-axisymmetric vehicles. To top it all off, the flight resulted in the setting of a new aeronautical speed record. The X-43A reached a speed of over Mach 7, or about 5,000 miles per hour faster than any known aircraft powered by an air-breathing engine has ever flown.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket accelerate after launch from NASA's B-52B launch aircraft over the Pacific Ocean on March 27, 2004. The mission originated from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif. Minutes later the X-43A separated from the Pegasus booster and accelerated to its intended speed of Mach 7. In a combined research effort involving Dryden, Langley, and several industry partners, NASA demonstrated the value of its X-43A hypersonic research aircraft, as it became the first air-breathing, unpiloted, scramjet-powered plane to fly freely by itself. The March 27 flight, originating from NASA's Dryden Flight Research Center, began with the Agency's B-52B launch aircraft carrying the X-43A out to the test range over the Pacific Ocean off the California coast. The X-43A was boosted up to its test altitude of about 95,000 feet, where it separated from its modified Pegasus booster and flew freely under its own power. Two very significant aviation milestones occurred during this test flight: first, controlled accelerating flight at Mach 7 under scramjet power, and second, the successful stage separation at high dynamic pressure of two non-axisymmetric vehicles. To top it all off, the flight resulted in the setting of a new aeronautical speed record. The X-43A reached a speed of over Mach 7, or about 5,000 miles per hour faster than any known aircraft powered by an air-breathing engine has ever flown.

Sim Ops 2002 R&D report images; SHARP (Slender Hypersonic Aerodynamic Research Probe) CTV Crew Transfer Vehicle) CGI image created by V Hawke & C Tang (Eloret Corp)

The second of three X-43A hypersonic research aircraft, shown here in its protective shipping jig, arrived at NASA's Dryden Flight Research Center, Edwards, California, on January 31, 2001. The arrival of the second X-43A from its manufacturer, MicroCraft, Inc., of Tullahoma, Tenn., followed by only a few days the mating of the first X-43A and its specially-designed adapter to the first stage of a modified Pegasus® booster rocket. The booster, built by Orbital Sciences Corp., Dulles, Va., will accelerate the 12-foot-long, unpiloted research aircraft to a predetermined altitude and speed after the X-43A/booster "stack" is air-launched from NASA's venerable NB-52 mothership. The X-43A will then separate from the rocket and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it impacts into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10 (seven and 10 times the speed of sound respectively) with the first tentatively scheduled for early summer, 2001. The X-43A is powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine, and will use the underbody of the aircraft to form critical elements of the engine. The forebody shape helps compress the intake airflow, while the aft section acts as a nozzle to direct thrust. The X-43A flights will be the first actual flight tests of an aircraft powered by an air-breathing scramjet engine.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

The third X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, California, on November 16, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 10.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket left the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on March 27, 2004. About an hour later the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 7.

Technicians prepare a Pegasus rocket booster for flight tests with the X-43A "Hypersonic Experimental Vehicle," or "Hyper-X." The X-43A, which will be attached to the Pegasus booster and drop launched from NASA's B-52 mothership, was developed to research dual-mode ramjet/scramjet propulsion system at speeds from Mach 7 up to Mach 10 (7 to 10 times the speed of sound, which varies with temperature and altitude).

A close-up view of the front end of a Pegasus rocket booster being prepared by technicians at the Dryden Flight Research Center for flight tests with the X-43A "Hypersonic Experimental Vehicle," or "Hyper-X." The X-43A, which will be attached to the Pegasus booster and drop launched from NASA's B-52 mothership, was developed to research dual-mode ramjet/scramjet propulsion system at speeds from Mach 7 up to Mach 10 (7 to 10 times the speed of sound, which varies with temperature and altitude).

Allen Parker, Mark Hagiwara, Paul Bean, Patrick Chan, Jonathan Lopez (seated), and Frank Pena comprise the Fiber Optic Sensing System team at NASA’s Armstrong Flight Research Center, in Edwards, California. The systems on the table measure strain and temperature, critical safety data for hypersonic vehicles that travel five time the speed of sound.

NASA's Hyper-x Program Manager, Vince Rausch talks about the upcoming launch of the X43A vehicle over the Pacific Ocean later this month from his office at NASA Langley Research Center in Hampton, VA. Hyper X is a high risk, high payoff program. The flight of the X43 A will demonstrated in flight for the first time, air breathing hypersonic propulsion technology. (Photo by Jeff Caplan)

The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden.

The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden.

The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden.

The NASA X-43A hypersonic research vehicle and its Pegasus booster rocket, mounted beneath the wing of their B-52 mothership, had a successful first captive-carry flight on April 28, 2001, Basically a dress rehearsal for a subsequent free flight, the captive-carry flight kept the X-43A-and-Pegasus combination attached to the B-52's wing pylon throughout the almost two-hour mission from NASA's Dryden Flight Research Center, Edwards, Calif., over the Pacific Missile Test Range, and back to Dryden.

The X-43A hypersonic research aircraft and its modified Pegasus® booster rocket are nestled under the wing of NASA's NB-52B carrier aircraft during pre-flight systems testing at the Dryden Flight Research Center, Edwards, Calif. The combined systems test was one of the last major milestones in the Hyper-X research program before the first X-43A flight. The X-43A flights will be the first actual flight tests of an aircraft powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine capable of operating at hypersonic speeds (above Mach 5, or five times the speed of sound). The 12-foot, unpiloted research vehicle was developed and built by MicroCraft Inc., Tullahoma, Tenn., under NASA contract. The booster was built by Orbital Sciences Corp., Dulles, Va. After being air-launched from NASA's venerable NB-52 mothership, the booster will accelerate the X-43A to test speed and altitude. The X-43A will then separate from the rocket and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it descends into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10.

As part of a combined systems test conducted by NASA Dryden Flight Research Center, NASA's NB-52B carrier aircraft rolls down a taxiway at Edwards Air Force Base with the X-43A hypersonic research aircraft and its modified Pegasus® booster rocket attached to a pylon under its right wing. The taxi test was one of the last major milestones in the Hyper-X research program before the first X-43A flight. The X-43A flights will be the first actual flight tests of an aircraft powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine capable of operating at hypersonic speeds (above Mach 5, or five times the speed of sound). The 12-foot, unpiloted research vehicle was developed and built by MicroCraft Inc., Tullahoma, Tenn., under NASA contract. The booster was built by Orbital Sciences Corp., Dulles, Va. After being air-launched from NASA's venerable NB-52 mothership, the booster will accelerate the X-43A to test speed and altitude. The X-43A will then separate from the rocket and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it descends into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10.

NASA's NB-52B carrier aircraft rolls down a taxiway at Edwards Air Force Base with the X-43A hypersonic research aircraft and its modified Pegasus® booster rocket slung from a pylon under its right wing. Part of a combined systems test conducted by NASA's Dryden Flight Research Center at Edwards, the taxi test was one of the last major milestones in the Hyper-X research program before the first X-43A flight. The X-43A flights will be the first actual flight tests of an aircraft powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine capable of operating at hypersonic speeds (above Mach 5, or five times the speed of sound). The 12-foot, unpiloted research vehicle was developed and built by MicroCraft Inc., Tullahoma, Tenn., under NASA contract. The booster was built by Orbital Sciences Corp., Dulles, Va.,After being air-launched from NASA's venerable NB-52 mothership, the booster will accelerate the X-43A to test speed and altitude. The X-43A will then separate from the rocket and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it descends into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10, with the first tentatively scheduled for late spring to early summer, 2001.

The first of three X-43A hypersonic research aircraft and its modified Pegasus® booster rocket recently underwent combined systems testing while mounted to NASA's NB-52B carrier aircraft at the Dryden Flight Research Center, Edwards, Calif. The combined systems test was one of the last major milestones in the Hyper-X research program before the first X-43A flight. The X-43A flights will be the first actual flight tests of an aircraft powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine capable of operating at hypersonic speeds (above Mach 5, or five times the speed of sound). The 12-foot, unpiloted research vehicle was developed and built by MicroCraft Inc., Tullahoma, Tenn., under NASA contract. The booster was built by Orbital Sciences Corp., Dulles, Va.,After being air-launched from NASA's venerable NB-52 mothership, the booster will accelerate the X-43A to test speed and altitude. The X-43A will then separate from the rocket and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it descends into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10.

Against the midnight blue of a high-altitude sky, Orbital Sciences’ Pegasus winged rocket booster ignites after being dropped from NASA’s B-52 mothership on a July 1991 flight. A NASA chase plane for the flight is also visible above the rocket and below the B-52.

Technicians secure the Space Test Program-Houston 6 (STP-H6) inside a transport truck at the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is being moved out of the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is being moved out of the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is inside the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. It is being prepared for its move to the SpaceX facility where it will be will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is inside the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. It is being prepared for its move to the SpaceX facility where it will be will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is moved to a transport truck at the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is secured inside a truck at the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is inside the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. It is being prepared for its move to the SpaceX facility where it will be will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is being loaded into a transport truck at the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is inside the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. It is being prepared for its move to the SpaceX facility where it will be will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is being prepared for its move from the Space Station Processing Facility high bay at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

The Space Test Program-Houston 6 (STP-H6) payload is moved out of the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida on March 19, 2019. The payload will be moved to the SpaceX facility where it will be stowed in the trunk of the Dragon spacecraft for delivery to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

The first X-43A hypersonic research aircraft and its modified Pegasus booster rocket were carried aloft by NASA's NB-52B carrier aircraft from Dryden Flight Research Center at Edwards Air Force Base, Calif., on June 2, 2001 for the first of three high-speed free flight attempts. About an hour and 15 minutes later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. Before this could be achieved, the combined Pegasus and X-43A "stack" lost control about eight seconds after ignition of the Pegasus rocket motor. The mission was terminated and explosive charges ensured the Pegasus and X-43A fell into the Pacific Ocean in a cleared Navy range area. A NASA investigation board is being assembled to determine the cause of the incident. Work continues on two other X-43A vehicles, the first of which could fly by late 2001. Central to the X-43A program is its integration of an air-breathing "scramjet" engine that could enable a variety of high-speed aerospace craft, and promote cost-effective access to space. The 12-foot, unpiloted research vehicle was developed and built for NASA by MicroCraft Inc., Tullahoma, Tenn. The booster was built by Orbital Sciences Corp. at Chandler, Ariz.

The first X-43A hypersonic research aircraft and its modified Pegasus booster rocket were carried aloft by NASA's NB-52B carrier aircraft from Dryden Flight Research Center at Edwards Air Force Base, Calif., on June 2, 2001 for the first of three high-speed free flight attempts. About an hour and 15 minutes later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. Before this could be achieved, the combined Pegasus and X-43A "stack" lost control about eight seconds after ignition of the Pegasus rocket motor. The mission was terminated and explosive charges ensured the Pegasus and X-43A fell into the Pacific Ocean in a cleared Navy range area. A NASA investigation board is being assembled to determine the cause of the incident. Work continues on two other X-43A vehicles, the first of which could fly by late 2001. Central to the X-43A program is its integration of an air-breathing "scramjet" engine that could enable a variety of high-speed aerospace craft, and promote cost-effective access to space. The 12-foot, unpiloted research vehicle was developed and built for NASA by MicroCraft Inc., Tullahoma, Tenn. The booster was built by Orbital Sciences Corp. at Chandler, Ariz.

The first X-43A hypersonic research aircraft and its modified Pegasus booster rocket were carried aloft by NASA's NB-52B carrier aircraft from Dryden Flight Research Center at Edwards Air Force Base, Calif., on June 2, 2001 for the first of three high-speed free flight attempts. About an hour and 15 minutes later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. Before this could be achieved, the combined Pegasus and X-43A "stack" lost control about eight seconds after ignition of the Pegasus rocket motor. The mission was terminated and explosive charges ensured the Pegasus and X-43A fell into the Pacific Ocean in a cleared Navy range area. A NASA investigation board is being assembled to determine the cause of the incident. Work continues on two other X-43A vehicles, the first of which could fly by late 2001. Central to the X-43A program is its integration of an air-breathing "scramjet" engine that could enable a variety of high-speed aerospace craft, and promote cost-effective access to space. The 12-foot, unpiloted research vehicle was developed and built for NASA by MicroCraft Inc., Tullahoma, Tenn. The booster was built by Orbital Sciences Corp. at Chandler, Ariz.

The first X-43A hypersonic research aircraft and its modified Pegasus booster rocket were carried aloft by NASA's NB-52B carrier aircraft from Dryden Flight Research Center at Edwards Air Force Base, Calif., on June 2, 2001 for the first of three high-speed free flight attempts. About an hour and 15 minutes later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 7. Before this could be achieved, the combined Pegasus and X-43A "stack" lost control about eight seconds after ignition of the Pegasus rocket motor. The mission was terminated and explosive charges ensured the Pegasus and X-43A fell into the Pacific Ocean in a cleared Navy range area. A NASA investigation board is being assembled to determine the cause of the incident. Work continues on two other X-43A vehicles, the first of which could fly by late 2001. Central to the X-43A program is its integration of an air-breathing "scramjet" engine that could enable a variety of high-speed aerospace craft, and promote cost-effective access to space. The 12-foot, unpiloted research vehicle was developed and built for NASA by MicroCraft Inc., Tullahoma, Tenn. The booster was built by Orbital Sciences Corp. at Chandler, Ariz.

The first of three X-43A hypersonic research aircraft and its modified Pegasus® booster rocket recently underwent combined systems testing while mounted to NASA's NB-52B carrier aircraft at the Dryden Flight Research Center, Edwards, California. The combined systems test was one of the last major milestones in the Hyper-X research program before the first X-43A flight. One of the major goals of the Hyper-X program is flight validation of airframe-integrated, air-breathing propulsion system, which so far have only been tested in ground facilities, such as wind tunnels. The X-43A flights will be the first actual flight tests of an aircraft powered by a revolutionary supersonic-combustion ramjet ("scramjet") engine capable of operating at hypersonic speeds above Mach 5 (five times the speed of sound). The X-43A design uses the underbody of the aircraft to form critical elements of the engine. The forebody shape helps compress the intake airflow, while the aft section acts as a nozzle to direct thrust. The 12-foot, unpiloted research vehicle was developed and built by MicroCraft Inc., Tullahoma, Tenn., under NASA contract. The booster, built by Orbital Sciences Corp., Dulles, Va., will accelerate the X-43A after the X-43A/booster "stack" is air-launched from NASA's venerable NB-52 mothership. The X-43A will separate from the rocket at a predetermined altitude and speed and fly a pre-programmed trajectory, conducting aerodynamic and propulsion experiments until it descends into the Pacific Ocean. Three research flights are planned, two at Mach 7 and one at Mach 10.

Anthony piazza, a researcher at NASA’s Armstrong Flight Research center in Edwards, California, works with high-temperature strain sensors. This test article is a bending load bar, which enables high-temperature optical strain sensor research up to 1,800 degrees Fahrenheit.

The X-37 advanced technology demonstrator flaperon unit was one of the first ever thermal and mechanical qualification tests of a carbon-carbon control surface designed for space flight. The test also featured extensive use of high-temperature fiber optic strain sensors. Peak temperatures reached 2,500 degrees Fahrenheit.

Anthony piazza, a researcher at NASA’s Armstrong Flight Research center in Edwards, California, works with high-temperature strain sensors. This test article is a bending load bar, which enables high-temperature optical strain sensor research up to 1,800 degrees Fahrenheit.

The Pegasus rocket that powered NASA's X-43A scramjet to almost Mach 10 test conditions leaves a bright arc in the Pacific sky during the boost phase.

NASA X-43A Monitor Station Operator Brad Neal performs final checks and pre-flight preparations aboard the B-52 for the third X-43A research vehicle Mach 10 flight on November 16, 2004. Takeoff of the B-52B mothership carrying the X-43A took place at 1 p.m., PST, with launch of the booster rocket/X-43A approximately an hour later.

Orbital Sciences Corp. technicians remove protective shrouds from the modified Pegasus booster before takeoff on the X-43A's Mach 9.6 record scramjet flight.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket accelerate after launch from NASA's B-52B launch aircraft over the Pacific Ocean on March 27, 2004. The mission originated from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif. Minutes later the X-43A separated from the Pegasus booster and accelerated to its intended speed of Mach 7.

NASA's B-52B mothership, escorted by two F-18s, makes a final flyover after its last research mission that launched the X-43A on its record Mach 9.6 flight.

The Hyper III was a full-scale lifting-body remotely piloted research vehicle (RPRV) built at what was then the NASA Flight Research Center located at Edwards Air Force Base in Southern California.

The third X-43A hypersonic research aircraft and its modified Pegasus booster rocket drop away from NASA's B-52B launch aircraft over the Pacific Ocean on November 16, 2004. The mission originated from the NASA Dryden Flight Research Center at Edwards Air Force Base, California. Moments later the Pegasus booster ignited to accelerate the X-43A to its intended speed of Mach 10.

NASA avionics technicians Randy Wagner and Terry Bishop make final adjustments on the scramjet-powered X-43A before its record Mach 9.6 flight.

Employees atop NASA Dryden's main building celebrate the return flyby of the B-52B aircraft after it launched the second X-43A aircraft on its successful flight.

The small size of the X-43A scramjet is evident in this nose-on view while mounted to its modified Pegasus booster under the wing of NASA's B-52B mothership.

The third X-43A hypersonic research aircraft and its modified Pegasus booster rocket accelerate after launch from NASA's B-52B launch aircraft over the Pacific Ocean on November 16, 2004. The mission originated from the NASA Dryden Flight Research Center at Edwards Air Force Base, California. Minutes later the X-43A separated from the Pegasus booster and accelerated to its intended speed of Mach 10.

With the X-43A and its booster rocket tucked under its right wing, NASA's venerable B-52B mothership climbs out after takeoff on its final research mission.

The Hyper-X X-43A project team in front of NASA's B-52B launch aircraft with the Pegasus booster and X-43A vehicle attached.

NASA engineers monitor mission progress from a Dryden control room prior to launch of the X-43A scramjet and its booster from NASA's B-52B mothership.

The third X-43A hypersonic research aircraft, attached to a modified Pegasus booster rocket, was taken to launch altitude by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, California, on November 16, 2004. About an hour later the Pegasus booster was released from the B-52 to accelerate the X-43A to its intended speed of Mach 10.

The second X-43A hypersonic research aircraft and its modified Pegasus booster rocket drop away from NASA's B-52B launch aircraft over the Pacific Ocean on March 27, 2004. The mission originated from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif. Moments later the Pegasus booster ignited to accelerate the X-43A to its intended speed of Mach 7.

NASA personnel in a control room during the successful second flight of the X-43A aircraft. front row, left to right: Randy Voland, LaRC Propulsion; Craig Christy, Boeing Systems; Dave Reubush, NASA Hyper-X Deputy Program Manager; and Vince Rausch, NASA Hyper-X Program Manager. back row, left to right: Bill Talley, DCI/consultant; Pat Stoliker, DFRC Director (Acting) of Research Engineering; John Martin, LaRC G&C; and Dave Bose, AMA/Controls.

NASA’s Orbiting Carbon Observatory-3 (OCO-3) and Space Test Program-Houston 6 (STP-H6) are in view installed in the truck of SpaceX’s Dragon spacecraft inside the SpaceX facility at NASA’s Kennedy Space Center in Florida on March 23, 2019. OCO-3 and STP-H6 will be delivered to the International Space Station on SpaceX’s 17th Commercial Resupply Services mission (CRS-17) for NASA. STP-H6 is an x-ray communication investigation that will be used to perform a space-based demonstration of a new technology for generating beams of modulated x-rays. This technology may be useful for providing efficient communication to deep space probes, or communicating with hypersonic vehicles where plasma sheaths prevent traditional radio communications. OCO-3 will be robotically installed on the exterior of the space station’s Japanese Experiment Module Exposed Facility Unit, where it will measure and map carbon dioxide from space to provide further understanding of the relationship between carbon and climate. CRS-17 is scheduled to launch from Space Launch Complex 40 on Cape Canaveral Air Force Station in late April.

This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

Attached to the same B-52B mothership that once launched X-15 research aircraft in the 1960s, NASA's third X-43A performed a captive carry evaluation flight from Edwards Air Force Base, California on September 27, 2004. The X-43 remained mated to the B-52 throughout this mission, intended to check its readiness for launch scheduled later in the fall.

Attached to the same B-52B mothership that once launched X-15 research aircraft in the 1960s, NASA's third X-43A performed a captive carry evaluation flight from Edwards Air Force Base, California on September 27, 2004. The X-43 remained mated to the B-52 throughout this mission, intended to check its readiness for launch scheduled later in the fall.

The Hyper III was a low-cost test vehicle for an advanced lifting-body shape. Like the earlier M2-F1, it was a "homebuilt" research aircraft, i.e., built at the Flight Research Center (FRC), later redesignated the Dryden Flight Research Center. It had a steel-tube frame covered with Dacron, a fiberglass nose, sheet aluminum fins, and a wing from an HP-11 sailplane. Construction was by volunteers at the FRC. Although the Hyper III was to be flown remotely in its initial tests, it was fitted with a cockpit for a pilot. On the Hyper III's only flight, it was towed aloft attached to a Navy SH-3 helicopter by a 400-foot cable. NASA research pilot Bruce Peterson flew the SH-3. After he released the Hyper III from the cable, NASA research pilot Milt Thompson flew the vehicle by radio control until the final approach when Dick Fischer took over control using a model-airplane radio-control box. The Hyper III flared, then landed and slid to a stop on Rogers Dry Lakebed.