You might think that Lewis Hamilton is the fastest Briton on four wheels, but spare a thought for Andy Green, whose rare but spectacular car adventures make the Formula 1 champion look like a snail.
Andy Green was an RAF pilot, flying Tornado F3 fighter jets. That wasn’t enough excitement for him, though, so he took up ’the best weekend job ever’ – someone who was looking for someone to drive a supersonic car and break the Land Speed Record!
In October 1997, Andy Green drove the Thrust SuperSonic Car to 763mph, breaking the Land Speed Record while hurtling past the speed of sound. No one else on Earth has come close to matching that epic achievement. Most supersonic vehicles normally fly high up in the atmosphere, or in space.
There’s a plan now to build an even faster car – one capable of a staggering 1,ooo mph – that’s faster than a bullet shooting out of a hand gun.
lt’s not just a question of taking the old Thrust SSC and pushing down a little harder on the accelerator pedal. For a fighter jet operating at high altitude, where the air is comparatively thin, supersonic speeds are easy to achieve. Down on the ground, in the densest regions of the atmosphere, jet engines have a severe limit on how fast they can go. Thrust SSC had twin jet engines; look at the front of the car and you see the two huge air Intakes. There comes a point, beyond the speed that Thrust could achieve, where the Intakes create too much air resistance and the car can’t go any faster.
The new car, Bloodhound sse, has an even sleeker design than Thrust. A single jet engine with a quite small air Intake pushes Bloodhound to a modest 30o mph, but thats just for starters. As Green flicks a switch and braces hlmselffor a savage burst of acceleration, a rocket engine flares into action and the car shoots forward even faster on a trail of flame. And it takes yet another hefty power plant, a 12-cyllnder racing car engine attached to a pump, to push ..,.. a whopping one ton of fuel through the rocket engine in just 20 seconds, as Bloodhound surges towards its maximum speed.
Bloodhound’s rocket engine has a solid-fuelled core made from hydroxy-terminated polybutadlene. That sounds complicated, like you’d need an advanced degree in chemistry just to pronounce it. But be ready for a surprise as to how cheap and easy HTPB is to make. It’s basically powdered tyre rubber. Hydrogen peroxide serves at very fullest strength as the oxidiser. Nothing can burn unless the oxidiser is flowing through the solid core. Bloodhound’s rocket booster can be switched off instantly if the warning lights come on.
Everyone knows that ‘rocket science’ is a mind-stretcher, but Green reckons Bloodhound is even more of a challenge to design and build. ‘If you think about it, we have an aerodynamically designed car, running on wheels, with a jet engine to get us on the move and a rocket to push us beyond that point. That’s at least three or four different technologies In one vehicle.’
Story courtesy from IET’s Flipside
Catch up with some other great technology facts in with ‘Techno Mum’ – every day in The Club with Luke at 5.30pm.
Techno Mum is supported by the Institution of Engineering and Technology – advancing and sharing technology
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