Feeds

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

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

Internet Security Threat Report 2014

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."

Remote control for virtualized desktops

More from The Register

next story
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
Designing and building an open ITOA architecture
Learn about a new IT data taxonomy defined by the four data sources of IT visibility: wire, machine, agent, and synthetic data sets.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
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.