Pratt & Whitney Rocketdyne Says Recent Ground Tests
Simulated Mach 5 Conditions
Pratt & Whitney Rocketdyne says it is a step closer to
flight testing the world's first hypersonic hydrocarbon-fueled and
-cooled scramjet engine. The X-51A Scramjet Engine
Demonstrator-WaveRider (SED-WR) successfully demonstrated key
flight clearance objectives in recent ground tests simulating Mach
5 flight conditions.
The X-51A SED-WR program is a collaborative effort of Pratt
& Whitney Rocketdyne, the US Air Force Research Laboratory, the
Defense Advanced Research Projects Agency (DARPA), NASA and The
Boeing Company to demonstrate extended-duration hypersonic flight
capability. Ground tests are being conducted at NASA Langley
Research Center's 8-foot High Temperature Tunnel in Hampton,
VA.
"The exceptional operation of the SJX61-2 flight clearance
engine and subsystems allows us to move forward to flight with
confidence," said Curtis Berger, hypersonics programs director,
Pratt & Whitney Rocketdyne. "Engine performance has met or
exceeded our predictions throughout the test series."
"We're extremely pleased with SJX61-2 test results to date,"
said Charlie Brink, X-51 program manager, Air Force Research
Laboratory. "This engine test is the culmination of several years
of hard work to mature the X-51's flight propulsion system and from
what we've seen so far -- the system is pretty much ready to go. We
have a few items that we're fine-tuning to optimize for flight but,
for the most part, the engine is operating just the way we want it
to."
The X-51 Flight Test Program plans to demonstrate the operation
of a scramjet engine within the Mach 4.5 to 6.0-plus range during
four flight tests beginning in 2009. The program will set the
foundation for several hypersonic applications, including access to
space, reconnaissance-strike and global reach.
The SJX61-2 duplicates the flight configuration propulsion
design, including a Full Authority Digital Engine Control (FADEC),
flight fuel pump and ethylene start system to orchestrate the
closed-loop thermal management and combustion systems that use JP-7
fuel.
Ground tests of the SJX61-2 and predecessor engine SJX61-1 have
verified thermal and structural capability of the propulsion system
in addition to validating the engine's start system, performance
and operability across the X-51 flight envelope.
The SJX61-2 is built on Pratt & Whitney Rocketdyne's
hypersonic propulsion development work during the Hydrocarbon
Scramjet Engine Technology (HySET) Program, under funding from the
US Air Force Research Laboratory. The engine's control system
shares technology derived from Pratt & Whitney's extensive
experience in military engine electronic controls and the company's
F119 turbofan powering the US Air Force's F-22 Raptor.