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Back to the Future, Part Two!
Originally
Published, November 2004
On November
16th, 2004, Jansen’s Aircraft Systems Controls (JASC), proudly
participated in a major milestone for the aerospace community as
the Hyper-X Research Vehicle (X-
43A) streaked out over the Pacific Ocean at nearly 10 times the
speed of sound. After getting a ride from a B-52 to 40,000 feet,
the Pegasus booster rocket accelerated the 12-foot-long unmanned
X-43A supersonic combustion scramjet vehicle from Mach 0.6 to a
speed close to Mach 10. At an altitude of 110,000 feet, the test
vehicle traveled at a speed of nearly 7,000 mph (approximately Mach
9.8).
This accomplishment
is truly a milestone for the aeronautics community - and the world.
It is the second time that an airframe-integrated scramjet (supersonic
combustion ramjet) engine was demonstrated in free flight. The initial
successful flight, in which JASC also participated, occurred on March
27th, 2004, where the test vehicle flew at a speed of Mach 7 at an
altitude of 95,000 feet.
JASC designed
and developed the electromechanically-actuated, electronically-controlled
ignitor and fuel control valves for the scramjet engine. After the
vehicle was jettisoned from the booster and achieved stable flight
at nearly Mach 9.8, the vehicle’s engine cowl door opened,
allowing air into the engine. The JASC silane ignitor valve was
then actuated, followed by the JASC hydrogen fuel valve to sustain
and regulate combustion in a process analogous to lighting and keeping
a match lit in a hurricane!
The two successful
flights were the culmination of over 40 years of effort to demonstrate
successful air-breathing hypersonic flight. This is proclaimed to
be “the Holy Grail of Flight” by veterans in the aerospace
engine community. Both of these X-43A flights superceded the previous
record holding air-breathing engine flight of Mach 3+ by the SR-71
Blackbird, and eclipses the X-15 record of Mach 6.7 which used a
rocket powered engine.
In addition
to the X-43A fuel control effort, JASC is pioneering the development
of high temperature, hydraulically actuated control valves that
will allow hydrocarbon fuels to be used in scramjet combustors.
The ultimate benefit lies in allowing for low cost, repetitive,
high-speed flights for both military and commercial purposes.
JASC
founder and president, Harv Jansen, is a true aerospace industry
pioneer. He was involved as an engineer on the development of the
SR-71’s J-58 engine and the world’s first liquid hydrogen/liquid
oxygen rocket engine designated the RL-10. The J-58 engine was as
innovative as the SR-71 airframe. To this day, the J-58 remains
a state of the art engine in aircraft propulsion. It was the first
and only dual-cycle aircraft engine, transitioning from a conventional
turbine engine to a ramjet engine at ~Mach 2. It was the first engine
to use fueldraulic controls, and the first to use metal seals on
tubing joints. Many materials and fluid advancements in use today
were spawned from the J-58 engine development program.
More Information:
Dryden
Flight Research and Langley
Research Center.
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