Bloodhound 1000 mph land-speed record project

Prasaja.web.id - "Faster than a speeding bullet," is what screenwriter Jay Morton used to say about Superman and, almost 80 years on, wing commander Andy Green could well surpass Clark Kent's alter ego if plans for the Bloodhound land-speed record car bear fruit.

Last week, the team announced its intention to commence record-breaking attempts on a 12-mile track across the Hakskeen Pan in the north-eastern corner of South Africa in 2011. 

And how fast will it go? Put it this way, if you fired what used to be the most powerful handgun in the world, Dirty Harry's .44 Magnum, at the tail of the rocket/jet car as it passed and Green toggled the 20,500lb thrust hybrid rocket as the revolver went off, the bullet would never hit the car.
In raw numbers, that's a muzzle velocity of 920mph for the .44, 300-grain charge bullet versus a terminal speed of 1,000mph-plus for the Bloodhound.
Even to contemplate such an idea, Green must be a superhero indeed. He already holds the land-speed record after his legendary display of cool in holding Thrust SSC at full throttle in a series of opposite lock slides up to and beyond the sound barrier.


"It got a lot calmer after it broke the barrier," he said. That was back in October 1997, when Thrust scorched across the Black Rock desert in Nevada at an average speed of 763.065mph.
"I still find it astonishing that we got the record with Thrust SSC," says Green, "even more so when you realise just how hard it is. I feel a great deal more comfortable about this attempt because of two things. Firstly, we know so much more about what we need than we did with Thrust; we are much more technically advanced. Second, the level of intellectual debate is so much more sophisticated this time around."
And why 1,000mph? Richard Noble, project director and no stranger to the record-breaking business, freely credits another. "It was Lord Drayson who suggested 1,000mph," he said, referring to Paul Drayson, British minister of science, businessman and amateur race driver. "When we heard that Steve Fossett had bought Craig Breedlove's car, Andy [Green] and I were thinking we would have to defend our record with about 800mph, but he said why not go for 1,000?"
But wasn't Thrust SSC supposed to be the end of land speed record-breaking? What else was there to achieve? After all, even the low-level air speed record, which is no longer contested, stands at 994mph.
But Noble has record-breaking coursing through his veins and while 1,000mph is an entirely arbitrary target, it needed to be superlative to achieve the educational effect that Drayson was after. As Ken Clarke, shadow minister for trade, told The Daily Telegraph last week: "A constant restraint on British business over the last 30 years is that we just don't produce enough engineers, scientists and technicians, this is crucially important."
So important, in fact, it could hinder Britain's manufacturing industry's ability to recover from the current recession. Drayson is hoping to inspire new students into engineering and manufacturing with what is known as the ''Apollo Effect'', the apparent correlation between the numbers of PhDs awarded to American students during the years of the US manned space programme from 1961-72. In those 11 years, PhDs rose from 12,000 to 30,000 a year and fell away in 1972 with the last Apollo 17 moon shot.
So Bloodhound is no mere quixotic tilt at a four-figure land speed, it's an education project with tacit Government support and 2,410 schools, 98 FE colleges and 33 universities signed up, with independent research showing the beginnings of a "mini Apollo" effect already taking place.
"Young students can't get into the bones of highly advanced defence projects or Formula One racing because of the secrecy involved," said Noble, "but with the Bloodhound project, they can see everything right down to the computational fluid dynamics."
The team reckons it needs £10 million to construct the car for a record attempt in 2011 or 2012 and while sponsorship is ever a problem, especially in a recession, Noble remains bullish. "We're doing well," he said, "and because of this education side of things, firms have now started to target us."
At more than 42 feet in length and 7.1 tons fully fuelled, the Bloodhound will be initially powered by an ex-development EJ200 military turbofan engine. This is a development of the Rolls-Royce XG-40 technology demonstrator and now powers the Typhoon Eurofighter – the team rescued its example en route to it being turned into a static exhibit.
On maximum reheat it produces about 20,000lb of thrust – enough, says Ron Ayers, the team's head of aerodynamics, to power the car to about 700mph.
At that point, just a few seconds into the run, a second power unit will be deployed, a hybrid rocket developed by Daniel Jubb, whom Ayers describes as "probably the only real genius on the team". Jubb, a 25-year-old, self-taught rocket scientist, runs a rocket manufacturing business and has been developing the Bloodhound's hybrid rocket motor for the past three years. An early version of the rocket motor was recently successfully tested in Nevada.
The hybrid propellant means the Bloodhound will have a degree of control unavailable to the solid fuel, light-blue-touchpaper variety of rockets, and is a lot less expensive than the liquid propellant variety. For safety, the team should be able to approach terminal speeds gently during a series of test runs.
The rocket will run for 20 seconds, providing 20,500lb of thrust burning 2,100lb of concentrated (86 per cent) hydrogen peroxide (known as HTP) as a liquid oxidiser, with a synthetic rubber, hydroxyl-terminated polybutadiene as the solid propellant.
If you think this is all a bit boggling, then check out the fuel pump: an 800bhp, 4.5-litre V12 racing engine from Menard Competition Technologies. It will operate at 12,000rpm, delivering 111lb of HTP per second at 1,100psi to the combustion chamber, which requires at least 620 shaft horsepower.
The forces acting on the structure are enormous. About 2.5G in acceleration and 3G in deceleration over Hakskeen's tough surface, together with the almost unbelievable surface forces acting on the vehicle, mean that Bloodhound has to be strong.
The front section is a racing car-style carbon-fibre tub. As well as driver Green, it contains the front suspension, steering, HTP tank and the ancillaries. The rear section is a steel spaceframe for the lower half and a carbon-fibre composite web structure on top.
The car has gone through at least 10 design evolutions since work started in October last year. Ayers quickly confirmed that the original 420lb rocket motor wouldn't have been enough to overcome the colossal drag at speeds nearing 1,000mph, so a larger 880lb rocket has to be used and in the interests of stability this will produce its thrust low in the frame, underneath the jet engine.
The wheels will be made of 35in-diameter solid titanium and keeping them on the ground will be a major challenge facing the team as they "poke through Jell-O", as USAF pilot Chuck Yeager put it after he piloted the world's first supersonic flight in October 1947.
Wheel tracks will be the tell-tale signs that the Bloodhound hasn't started to take to the air. "No wheel tracks, no record," said John Piper, the team engineering director. "We can't do this in the air."
Ayers added: "With Thrust SSC, because the desert had exploded behind the car, the timekeepers had to feel down through the dust for the impacted material where the wheels had passed over."
Bloodhound is named after the Bristol Bloodhound, a formidable twin jet/quad rocket, Mach-2.7, surface-to-air missile (SAM) system that protected Nato's northern borders in the Fifties and Sixties. Ayers was the aerodynamics designer on the SAM missile, which did its deterrence job so well it was never once fired in anger. Since then he has worked out his "retirement" on land-speed record attempts for Noble and the JCB Dieselmax project, which in August 2006 set a diesel-powered record of 350.092mph.
Safety is paramount for Ayers, who recalls a visit from three-times land-speed record holder Art Arfons to the Thrust team in 1997. Ayers showed Arfons the computational fluid dynamics predictions of what would happen to Thrust. "He said, 'Aw Ron, you're just spoiling it for us country lads with this stuff. We're just doing it for the fun.'
"In other words," said Ayers, "with no understanding of the physics or the stresses involved, he was prepared to climb into his car and do 600mph. At 1,000mph we're going to be a damn sight safer than that. Besides, Andy [Green] is a good friend of mine, I was at his wedding last year."
While the team is confident it can overcome the daunting technical hurdles ahead, privately individuals admit that there are still unknowns. Ayers is wary of the potential surface loadings on the coachwork as the Bloodhound heads towards 1,000mph.
And they are going to have to get their skates on, too. At least three rival teams are aiming to break the existing record. In Australia, Rosco McGlashan's rocket-powered car, Aussie Invader 5R, is under development with the aim of pushing the land-speed record well beyond Thrust SSC's 763mph. The North American Eagle team has been developing a wheeled adaptation of an F-104 Starfighter military jet to run at speeds over the sound barrier.
There's also Steve Fossett's LSR team. The billionaire adventurer had started to fund a complete rebuild of Craig Breedlove's 1997 LSR car when, in 2007, he went missing in a light aircraft. A year later the plane's wreckage and Fossett's remains were discovered. Work on the car has been completed and the team is looking for a new sponsor/owner.
Of the four, it is hard not to give the Bloodhound team the betting odds on at least beating the record, even if 1,000mph seems almost fantastical.
Noble, Green and Ayers have a sound track record and if any group can inspire young people into the worlds of science and engineering, then it has to be them, although we can't see many folk wanting to step into Andy Green's superhuman shoes.

http://www.telegraph.co.uk

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Setelah baca, alangkah baiknya jika mengisi komentar di sini, agar terjadi silahturahmi yang baik.. heheh :)