Feeds

NASA working on boomless supersonic jets

And contrived acronyms

Build a business case: developing custom apps

NASA has announced the completion of a series of flight tests aimed at reducing the "sonic boom" effect, one of the major downsides of supersonic aircraft.

Two custom-modified F-15 fighter jets were used in the test programme, referred to by NASA as Lift and Nozzle Change Effects on Tail Shock (LaNCETS*). Flying faster than sound, the lead F-15 used its custom-fitted canards (small winglets ahead of the main wings) to modify how much lift was generated by the main wing; it also changed its engine nozzle configuration.

NASA's two F-15 test craft. Note the canards added to the left-hand jet.

NASA's pimped-out Eagle test birds.

These changes altered the conical shockwaves trailing behind the plane, measured by the second F-15 using nose-mounted sensors to probe the wake of the jet just ahead. It is this shock front, trailing behind a supersonic aircraft, which produces the loud "sonic boom" when it hits the ground. The boom produced by Concorde was sufficient that the mighty Mach-2 airliner was largely restricted to subsonic speeds when over land, and meant that the London-New York route was the only one it could routinely serve.

Nobody is really planning another supersonic airliner right now: but some US makers think there would be a market for supersonic business jets, able to whisk billionaires and CEOs from continent to continent faster than today's plutocraft. But they wouldn't be much use if they couldn't go supersonic over land.

Hence the desire for boomless (or anyway, less boomy) supersonic flight. NASA has been working on fundamental research for a while, aiming to help the US aviation industry crack the technical issues. One recent effort, for instance, saw Gulfstream "Quiet Spike" nose poles fitted to NASA jets, to see if the shock cone from the spike might mask or mitigate the noise from the rest of the aircraft.

The just-completed LaNCETS effort uses a different approach, looking to find out just how different lift loads and engine nozzle shapes affected the shape and intensity of the shock cones behind a plane. The chase F-15 used differential-GPS augmented satnav kit to measure its position with respect to the lead craft exactly, allowing the sensor readings to be precisely mapped into a 3D database.

The test results "will be made available to interested university and industry partners in order to further their research objectives", according to NASA. ®

*Pah. We'd have gone with Supersonic Flight Acoustics Testing Centred on Advanced Transportation for the Superwealthy (SuperFATCATS for short).

Secure remote control for conventional and virtual desktops

More from The Register

next story
Boffins attempt to prove the UNIVERSE IS JUST A HOLOGRAM
Is this the real life? Is this just fantasy?
Our LOHAN spaceplane ballocket Kickstarter climbs through £8000
Through 25 per cent but more is needed: Get your UNIQUE rewards!
China building SUPERSONIC SUBMARINE that travels in a BUBBLE
Shanghai to San Fran in two hours would be a trick, though
LOHAN tunes into ultra long range radio
And verily, Vultures shall speak status unto distant receivers
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
Galileo, Galileo! Galileo, Galileo! Galileo fit to go. Magnifico
I'm just a poor boy, nobody loves me. But at least I can find my way with ESA GPS by 2017
Astronomers scramble for obs on new comet
Amateur gets fifth confirmed discovery
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
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.
Backing up distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.