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A team of British engineers have fired up the rocket that they hope will propel their car to speeds in excess of 1,000mph, smashing the land speed record. Rocket scientist Daniel Jubb sets the scene

It's 5am in the Mojave Desert and all is eerily quiet and still. The team has been up for hours to beat the sun before stifling heat makes working outside unbearable.

Our new 18-inch-diameter hybrid rocket is sitting on a test stand, looking alien in the clear dawn light. We've been building and testing 6-inchers for the past 12 months, progressing from monopropellant (a rocket using a single liquid propellant) to hybrids (a rocket using a liquid oxidiser and a solid fuel) as we learn how to control the power output. Now everyone is curious to see how a bigger version will perform.

The small rockets were comparatively easy to handle, but we still had a few blow up. Scaling up to 18 inches is a challenge because the design does not scale directly. If my calculations are correct, five minutes from now we'll be witnessing a spectacular jet of flame shooting 50 feet out of the back end of the rocket, accompanied by an extraordinarily angry burst of noise…

Either that, or one hell of an explosion…

These hybrid rockets are custom built for the Bloodhound Project to design and build a 1000mph car, Britain's latest attempt at the world land speed record. This project really pushes technology to new levels as we improve design and efficiency.

But this isn't just petrol heads and science geeks playing boy racer in the desert. We aim to truly inspire the next generation of Britain's kids to engage in maths, science and technology in the classroom.

As a 25-year-old rocket scientist, I can relate to why kids are excited about science. My enthusiasm for rocketry began at a young age. My grandfather and I began building model rockets when I was 10. After hundreds of launches we decided that to reach really high altitudes (in 1996 our objective was to get to 20,000 feet) we needed to stop using the model rocket kits and start building our own rocket motors.

In order to do this we had to gather knowledge from every available source, not only on the technical aspects but also on the legal aspects of manufacture, storage and transport of explosives and the financial aspects of running a company.

The rocket I'm working on now uses 105lb of high test peroxide (HTP) per second to burn the solid fuel packed into the combustion chamber. We will use about 1 tonne for each run of the Bloohound SSC (SuperSonic Car). To power the HTP pump, we have an 800 horsepower V12 race engine. The pump forces the HTP into a catalyst pack at the top of the combustion chamber, where the HTP is decomposed into superheated steam and oxygen.

The oxygen is used to burn the solid fuel – a synthetic rubber hydroxyl-terminated polybutadiene (HTPB), which is also used in aircraft tyres.

We want to propel Bloodhound SSC from zero to 1000mph in just 40 seconds. That's six miles to reach target velocity. Because of the way hybrid rockets work, it is difficult to throttle them without a substantial reduction in efficiency. You need to load them with enough fuel to burn for a specific amount of time.

So to get the car rolling, we're using a jet engine from a Eurofighter Typhoon. Once it hits 300mph, we'll fire up the rocket for 20 seconds to carry the car through the sound barrier and past mach 1.4. The car will only start to slow when the rocket fuel burns out and the jet has been switched off.

To break the world land speed record we're required to take two runs through a measured mile within a one-hour time limit, and in order to do this we need a 12-mile track. We have to physically stop the car at mile 12 when the rocket propellants have been expended. We pick it up, turn it around, run a full systems check and re-fuel, all in blistering 40C heat. Managing all this is almost akin to landing the space shuttle, refuelling and re-launching it on another mission, i

Tags: Bloodhound SSC, Physics, Chemistry, Science, Engineering, Motoring, Research and development, Technology, UK news, World news, guardian.co.uk, Blogposts

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Bloodhound engineers test-fire rocket for supersonic car was originally published by Technology: Motoring | guardian.co.uk. Read the full story by clicking here.