October 26, 2008
Pat Malone
Say hello to the
Bloodhound SSC, a 42ft-long vehicle (you can hardly call it a car) in which
Wing Commander Andy Green, a former RAF pilot, will attempt to break his own
land-speed record. It is 11 years since Green became the first driver to travel
faster than the speed of sound, hitting 763mph in the Thrust SSC (supersonic
car). The Bloodhound is set to beat that by more than 200mph, reaching 1.4
times the speed of sound. Blink and you’ll miss it. Really. In the sixth of a
second it takes you to blink, it will travel nearly the length of a football
pitch. This monstrous contraption is blessed with the power of 1,200 family
cars. The fuel pump alone has 800 horsepower. First, though, Green and
Richard Noble, the team leader, need £10m in sponsorship to develop and build
the car. Noble, who also headed up the Thrust SSC team in 1997, has already got
endorsement from Lord Drayson, the science minister, and the gift of the
Typhoon engine from the Ministry of Defence, for whom Green works. If all goes according to
plan (and that’s a big if), construction will be completed by the end of next
year, leading to the 1,000mph record attempt in 2011. It will put the
land-speed record firmly – possibly for the foreseeable future – in the hands
of the British, with a supersonic speed that’s actually faster than the 994mph
low-altitude speed record for an aircraft. ·
Bloodhound car could reach 1,000mph ·
Pictures: Bloodhound SSC supercar That
kind of velocity has to be built up in stages. First the Typhoon engine
launches the car. At 300mph, the Falcon solid-fuel rocket engine (designed and
built in Britain) will kick in, with its peroxide fuel being slammed into it at
a pressure of 1,200psi by the V12 racing engine. With nine tonnes of thrust
coming from the jet engine and another 12 tonnes from the rocket, the car will
accelerate within seconds beyond the muzzle velocity of a .357 Magnum. Enormous
forces will build up on the bodywork, which will have to withstand greater
pressure than a military submarine – more than 12 tonnes per square metre. Aerodynamic forces will
alternately make it want to fly and dive into the ground. Computer-controlled
“winglets” (see graphic), on either side of the nose, will hopefully prevent
this. The wheels turn at 10,500rpm, their rims subjected to g-forces equal to
50,000 times the force of gravity. Each component of the car
will have to be precision-made. The wheels will be machined from titanium, but
who can machine a block of titanium that big? It’s never been done. Within five
miles, the Bloodhound SSC will smash through 1,000mph before beginning a savage
deceleration that will subject the driver to a sustained pressure of minus 3g.
The mathematicians and aerodynamicists – including the fabled (in engineering
circles) Ron Ayers, who developed the Bloodhound missile in the 1950s, after
which the project is named – believe it is possible. But at such superhuman
speeds, if something goes horribly wrong, the only difference between 700mph
and 1,000mph is how thinly you’re spread across the ground. Fortunately, having
already set one land-speed record, Green, 46, has proved he can drive at insane
speeds, making counterintuitive steering corrections, reading all the dials
while checking instruments and talking on the radio at the same time. He remains sanguine about
the dangers: “It’s all about risk minimisation and risk management,” he says,
demonstrating the sort of calm logic that earned him a first-class degree in
mathematics from Oxford. “It would be wrong to say I’m not nervous about it,
but I’m sure there is a very high probability that the goal can be achieved.” The speed of sound varies
according to altitude, but at sea level it is about 761mph. As the car
approaches that speed, shockwaves will build up in front of the nose cone and
as it goes past the sound barrier it will burst through a wall of air pressure,
creating an eardrum-shattering sonic boom. “The critical thing is to
keep the car on the ground and going in the right direction,” says Green. “It’s
not a case of saying ‘blimey, this is fast’. If anything, it’s another sensation.
It’s like the slow-speed feeling you get just before a car crash – only it
lasts for about two minutes.”

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