Boeing Expertise Fuels X-43A Hypersonic Research Flights
The flight of NASA’s X-43A at
seven times the speed of sound got a lift from Boeing research
expertise with hypersonic vehicles and spacecraft.
On Saturday, a NASA Dryden Flight Research Center B-52 aircraft flown from
Edwards Air Force Base, Calif., carried the X-43A off the California coast,
where it was launched just before 2 p.m. PST over the Pacific Ocean mounted on
a booster rocket.
The booster took the X-43A up to its test altitude of about 95,000 ft.,
where the X-43A separated and flew freely for several minutes. During the free
flight, the scramjet engine operated for about 10 seconds and the X-43A
successfully achieved its test speed of Mach 7.
“This successful flight is an important step toward validating the use of
advanced air-breathing propulsion technology for achieving more rapid global
travel and routine, affordable access to space,” said Bob Krieger, president
of Phantom Works, Boeing’s advanced R&D unit. “Applied to civil, military and
space systems, this technology has the potential to open new frontiers in
aerospace.”
Boeing Phantom Works is teamed with prime contractor ATK GASL to develop
and build the X-43A or Hyper-X for NASA. Boeing designed the vehicle, the
airframe thermal protection systems and flight control and navigation systems.
ATK GASL was responsible for vehicle fabrication, assembly, systems
integration and testing in addition to providing the scramjet engine. The
booster is a modified Pegasus rocket built by Orbital Sciences Corp.
The 12.3-foot-long X-43A is powered by a scramjet, or supersonic
combustion ramjet engine. As air-breathing engines, scramjets have
significantly fewer moving parts than traditional turbojet engines, and do not
require oxidizer to be carried onboard for combustion like conventional rocket
engines do. Scramjets allow for the design of smaller, simpler, more
affordable reusable vehicles for potential space, military and civil
applications.
Hypersonic flight, defined as flying at least five times the speed of
sound, remains a mostly unexplored region. At those speeds, metals can melt or
vaporize almost instantly, and aerodynamic control must be extremely precise.
Additionally, strong shockwaves are created that can cause exceptionally high
temperatures and forces on various parts of the airframe.
To meet these challenges, the X-43A employs a tile-based thermal
protection system, carbon-carbon composites, and high temperature-resistant
metals; a control system designed to deal with the rapid changes in forces and
motions expected at Mach 7; and a special control technique to sense and
prevent disruption of the supersonic airflow through the inlet, which would
dramatically reduce engine thrust.
Boeing has explored the challenges of hypersonic flight since the 1950s,
beginning with the X-15 to the space shuttle to the X-43A.
Phantom Works is currently teamed with Pratt & Whitney on the Scramjet
Engine Demonstrator – WaveRider program for the Air Force. Additional Phantom
Works projects include the FALCON Hypersonic Cruise Vehicle program for DARPA
and the HyFly hypersonic missile demonstrator program for DARPA and the Navy.
“Many challenges remain to be overcome, particularly in developing
efficient and high-performing engines for sustained hypersonic flight,” said
Tom Harsha, Boeing Phantom Works X-43A program manager. “But we’ll learn
important lessons from the X-43A about the technology we’ll need to make
hypersonic flight practical.”
NASA’s Langley Research Center in Hampton, Va., and Dryden Flight Research
Center near Edwards, Calif., jointly conduct the Hyper-X program.
Boeing Phantom Works is the advanced research and development unit and a
catalyst of innovation for The Boeing Company. It provides advanced solutions
and innovative, breakthrough technologies that reduce cycle time and cost
while improving the quality and performance of aerospace products and
services.
