Feeds

X-51 hypersonic scramjet test: Flameout at Mach 5?

Boffins still 'ecstatic' after 3-minute strato-streak

Intelligent flash storage arrays

US government aerospace agencies have achieved the world's first hypersonic scramjet flight using hydrocarbon fuel. The test did not go perfectly, but further flights will follow; organisers said they were "ecstatic" with progress thus far.

Concept graphic of the Waverider in flight, during rocket boost. Credit: AFNS

Shockwave riding supersonic-combustion-ramjet hypersonic hotness.

The X-51A "Waverider" craft was dropped from a modified B-52 bomber test mothership 50,000 feet above Point Mugu sea firing range off the California coast at about 6pm last night UK time (10am local). Four seconds later a rocket booster taken from a tactical missile fired, accelerating the Waverider to Mach 4.5 before being jettisoned. The airframe doesn't work like a normal aeroplane: it actually surfs on the sonic shockwaves trailing back from its nose, hence its name.

The hypersonic X-51A ignited, burning a mixture of ethylene and JP-7 jet fuel, and once well alight switched over to all-jetfuel operation. Normal turbojets can't operate at hypersonic speeds; the Waverider is a ramjet, whose intake air is simply scooped in at the front due to its speed rather than being crammed in by compressor blades.

But normal ramjets have to slow that air down to subsonic speed inside themselves so as to avoid blowing out the flame in their combustion chamber. This limits them to a top speed of perhaps Mach 3.5. The Waverider, though, is a scramjet - a supersonic combustion ramjet - which lets the air blow through it supersonically. It is thought by its designers to be capable of burning for 300 seconds to reach Mach 6.

The X-51A didn't fulfil that potential yesterday, however. Having lit up it burned for around 200 seconds, reaching approximately Mach 5 and climbing to 70,000 feet. According to a statement issued by Boeing (whose Phantom Works plant built the Waverider):

Something then occurred that caused the vehicle to lose acceleration. At that point, the X-51A was terminated as planned.

It's possible to speculate that the flame in the Waverider's SJY61 scramjet, built by Pratt & Whitney Rocketdyne, simply blew out. Project officials are still happy with the test, and seem confident that they will be able to achieve the designed speed before running out of test craft - there are three more.

"We are ecstatic to have accomplished most of our test points on the X-51A's very first hypersonic mission," said Charlie Brink, X-51A honcho at the US Air Force Research Laboratory.

"No test is perfect," he added. "But anyone will tell you that we learn just as much, if not more, when we encounter a glitch."

Security for virtualized datacentres

More from The Register

next story
Boffins who stare at goats: I do believe they’re SHRINKING
Alpine chamois being squashed by global warming
What's that STINK? Rosetta probe shoves nose under comet's tail
Rotten eggs, horse dung and almonds – yuck
Comet Siding Spring revealed as flying molehill
Hiding from this space pimple isn't going to do humanity's reputation any good
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
Kip Thorne explains how he created the black hole for Interstellar
Movie special effects project spawns academic papers on gravitational lensing
LONG ARM of the SAUR: Brachially gifted dino bone conundrum solved
Deinocheirus mirificus was a bit of a knuckle dragger
prev story

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.