Feeds

Ordinary-fuel scramjet prototype suffers test failure

'HyFly' crashes, fails to burn

Application security programs and practises

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. ®

Build a business case: developing custom apps

More from The Register

next story
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
BEST BATTERY EVER: All lithium, all the time, plus a dash of carbon nano-stuff
We have found the Holy Grail (of batteries) - boffins
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Forty-five years ago: FOOTPRINTS FOUND ON MOON
NASA won't be back any time soon, sadly
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.