Feeds

Mixed bag of motors lifts India's budget Mars shot

Solid rocket boosters and hypergolic cocktails

Top three mobile application threats

India's budget* Mars Orbiter Mission (MOM) last week thundered heavenwards from Sriharikota spaceport atop a Polar Satellite Launch Vehicle (PSLV), en route to a rendezvous with the Red Planet in September 2014.

PSLV-C25 blasts off. Pic: ISRO

PSLV-C25 blasts off. Pic: ISRO

Weighing in at 500kg, plus 850kg of fuel, the MOM spacecraft was well within the 1,800kg lifting capability of the PSLV-XL ("extended") variant tasked with getting it Marswards.

The PSLV is an interesting beast, boasting a mix of solid rocket and hypergolic engine tech.

PSLV-C25 on the launchpad. Pic: ISRO

PSLV-C25 on the launchpad. Pic: ISRO

Its principal first-stage thruster boasts a mighty 139 tonnes of hydroxyl-terminated polybutadiene (HTPB) bound propellant. Strapped around this core are six solid rocket boosters (SRBs), four of which fire at launch and two which fire around 30 seconds into the flight.

Such engines are a popular choice among the rocketry big-hitters. The European Space Agency's (ESA) Ariane 5 uses two SRBs to provide an extra kick up the backside. They burn ammonium perchlorate composite propellant (APCP) - aluminium powder and oxidising ammonium perchlorate held in HTPB.

The PSLV's second-stage booster is, by contrast, a locally built Vikas engine burning approximately 40 tonnes of unsymmetrical dimethylhydrazine (UDMH) and nitrogen tetroxide (N2O4).

The Vikas Engine. Pic: MTAR Technologies

The Vikas Engine. Pic: MTAR Technologies

Many nations are now ditching hypergolic cocktail burners in favour of engines using less volatile fuels.** Russia's long-serving Proton, for example, uses no less than 10 N2O4/UDMH motors - six in the first stage, three in the second and one in the third.

However, its planned replacement, the Angara 5 rocket, will rely on a kerosene/LOX-powered "Universal Rocket Module" first stage.

Similarly, China is eyeing kerosene/LOX for future versions of its Long March, which currently rise heavenwards thanks to N2O4 and UDMH.

Back at the PSLV, meanwhile, once the Vikas has done its job, seven tonnes of solid propellant power the third stage. After that, it's back to a hypergolic blend for the fourth stage, as two engines slurping monomethylhydrazine (MMH) and nitrogen oxides finally send the payload on its way.

The PSLV's exotic rocket motor mix has propelled it close to the top of the reliability league table. To date, it has executed "24 continuously successful flights", a performance described by the Indian Space Research Organisation as "superb". ®

Bootnotes

*£45m ($74m) - small change in Mars mission terms.

**For more on rocket motor propellants, see "Rocket boffinry in pictures: Gulp the Devil's venom and light a match".

3 Big data security analytics techniques

More from The Register

next story
Red-faced LOHAN team 'fesses up in blown SPEARS fuse fiasco
Standing in the corner, big pointy 'D' hats
KILLER SPONGES menacing California coastline
Surfers are safe, crustaceans less so
Opportunity selfie: Martian winds have given the spunky ol' rover a spring cleaning
Power levels up 70 per cent as the rover keeps on truckin'
KILLER ROBOTS, DNA TAMPERING and PEEPING CYBORGS: the future looks bright!
Americans optimistic about technology despite being afraid of EVERYTHING
Discovery time for 200m WONDER MATERIALS shaved from 4 MILLENNIA... to 4 years
Alloy, Alloy: Boffins in speed-classification breakthrough
Liftoff! SpaceX Falcon 9 lifts Dragon on third resupply mission to ISS
SpaceX snaps smartly into one-second launch window
Elon Musk's LEAKY THRUSTER gas stalls Space Station supply run
Helium seeps from Falcon 9 first stage, delays new legs for NASA robonaut
prev story

Whitepapers

Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.