Feeds

Ordinary-fuel scramjet prototype suffers test failure

'HyFly' crashes, fails to burn

Providing a secure and efficient Helpdesk

An innovative hypersonics programme has suffered a failure, with a prototype scramjet missile failing to perform properly and crashing into the Pacific after less than a minute in the air.

HyFly dual-combustion ramjet in windtunnel tests

It works well here...

Aviation Week reports that a "HyFly" test airframe was launched from an F-15 fighter above a weapons range on the California coast on January 16. The magazine quotes a Pentagon spokesman as saying that the test was "unsuccessful... The scramjet engine did not operate as expected and after approximately 58 seconds of flight, the vehicle impacted the ocean."

The HyFly ("Hypersonic Flight Demonstration") is an especially cool kind of hypersonic jet, as it is intended to run on relatively ordinary JP-10 hydrocarbon fuel rather than on hydrogen like most planned scramjets. This is good, because hydrogen is difficult to store and extremely bulky compared to denser, more normal fuel.

As an example, the proposed A2 hydrogen hypersonic airliner is bigger than an Airbus A380 superjumbo, yet it can carry barely a third as many passengers because it is mainly a vast cylindrical hydrogen tank.

Scramjets normally use hydrogen because it burns especially quickly and easily, which offers a decent chance of maintaining combustion even when air is flowing through the engine supersonically - hence the name, supersonic combustion ramjet. Normal ramjets slow the air down to subsonic speed, but the resulting drag limits them to the Mach 3-4 range.

The HyFly uses a technology called dual combustion ramjet, or DCR, in which there are separate intakes shaped so as to produce both subsonic and supersonic flows into the engine. The heavy hydrocarbon fuel burns first in a subsonic flow, breaking down into lighter products which can then - hopefully - finish combusting in a supersonic-flow part of the engine.

HyFly mounted on a launch aircraft

...not so well here.

The DCR compromise was conceived at the Johns Hopkins University Applied Physics Laboratory. It is now being taken forward jointly by the US Office of Naval Research and DARPA - the American warboffinry bureau with deep pockets and a revolving door to the mad scientists' asylum.

DARPA had hoped that DCR might let a smart missile running on JP-10 get up to Mach 6 cruise speed and fly 400 nautical miles to its target. However, the recent test failure follows a "partial success" last December, in which HyFly reached only Mach 3.5 - failing to beat ordinary ramjet performance. The two failures could put a question mark over the whole DCR concept.

Still, a half-scale prototype job did briefly reach Mach 5.5 in 2005, and there have been successful windtunnel tests at Mach 6+.

Aviation Week reports that this "was believed to be the last attempt in the DARPA-led effort to evaluate the weapon's rocket-boosted ramjet-scramjet propulsion system". Other reports had it that DCR was a likely candidate to propel DARPA's upcoming "Blackswift" reusable hypersonic plane - but this might now be in doubt. ®

Internet Security Threat Report 2014

More from The Register

next story
MARS NEEDS WOMEN, claims NASA pseudo 'naut: They eat less
'Some might find this idea offensive' boffin admits
LOHAN crash lands on CNN
Overflies Die Welt en route to lively US news vid
Experts brand LOHAN's squeaky-clean box
Phytosanitary treatment renders Vulture 2 crate fit for export
No sail: NASA spikes Sunjammer
'Solar sail' demonstrator project binned
Carry On Cosmonaut: Willful Child is a poor taste Star Trek parody
Cringeworthy, crude and crass jokes abound in Steven Erikson’s sci-fi debut
Origins of SEXUAL INTERCOURSE fished out of SCOTTISH LAKE
Fossil find proves it first happened 385 million years ago
Human spacecraft dodge COMET CHUNKS pelting off Mars
Odyssey orbiter yet to report, though - comet's trailing trash poses new threat
You can crunch it all you like, but the answer is NOT always in the data
Hear that, 'data journalists'? Our analytics prof holds forth
prev story

Whitepapers

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.
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.
Three 1TB solid state scorchers up for grabs
Big SSDs can be expensive but think big and think free because you could be the lucky winner of one of three 1TB Samsung SSD 840 EVO drives that we’re giving away worth over £300 apiece.
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.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.