The British have a long history of slightly unhinged motorsport projects, from shed-built hill-climb specials through to the Garagista teams who reinvented Formula 1 and sports-car racing in the 1950s and ’60s. But even by the standards of such eccentric endeavor, the Bloodhound SSC project stands out as something special, a car that’s being built to push the land-speed record over 1000 mph.
The quest to build the fastest wheeled vehicle has always been the ultimate “because it’s there” accomplishment. And, it must be said, a curiously British obsession, with U.K drivers having held the title for 75 of the 117 years since the first one was set (by a Frenchman in an electric car, at 39 mph.) If Bloodhound succeeds, it will be breaking another British-set record, Thrust SSC’s run to a just-supersonic 763 mph in 1997. The presence of many Thrust veterans on the Bloodhound project suggests that this obsession with ultimate speed is a long-lived one.
Although the Bloodhound project began in 2008, things are now starting to come together. Literally; with the car itself being assembled in the center of the team’s industrial unit near Bristol. Construction is well advanced, with the car scheduled to make its first shakedown runs next month before heading to South Africa later this year. There, on a specially prepared 12-mile-long course on the Hakseen Pan, a natural salt flat, Bloodhound will attempt to break the 800-mph barrier, before returning next year with a more powerful car to try for 1000 mph.
Although the fundamentals are the same as when we last told you about the car in 2012, many of the details have been changed—and the car has been redesigned several times. As per the original plan, Bloodhound will use both jet and rocket power, and be driven by Andy Green, the serving RAF pilot who drove Thrust SSC to the record back in ’97. But while Bloodhound’s prime mover is the same—a Rolls-Royce EJ100 jet engine more usually found in the Eurofighter Typhoon fighter plane—the rest of the powertrain has evolved considerably. Plans for the team to build its own hybrid rocket motor have been nixed, instead it will use reusable motors made by Norwegian-Finnish aerospace company NAMMO; a single one fitted for the 800-mph target runs and a trio for the 1000-mph attempt.
The numbers are beyond impressive, and most of the way to being downright scary. By itself the jet engine will produce 20,000 pounds of thrust, with each NAMMO adding 27,500 to that. Meaning, in full-on configuration, Bloodhound will have 102,500 pounds of thrust. Sadly the original, and compellingly mad, idea of using a Cosworth Formula 1 engine as a pump for the peroxide used as an oxidizer by the rocket motors has been canned. A stock supercharged Jaguar V-8 will do the job instead.
From the outside, Bloodhound’s headquarters is completely anonymous, between a kitchen-supply company and a crane-hire business. But inside the low-rise industrial unit is a hive of activity, with the mostly built aluminum chassis looking, unsurprisingly, like an aircraft fuselage. It’s being built to the same standards. “This is far closer to aeronautical than automotive engineering,” says Mark Chapman, Bloodhound’s chief engineer. As his resume includes Boeing, British Aerospace, five years working on the F-35 Joint Strike Fighter and a stint at McLaren Formula 1, he should know. It’s a point reinforced by the presence of four uniformed RAF technicians on the day we visit, working assembling the tail section; they’ve been seconded to the project to, officially, gain experience working at advanced problem-solving.
The overwhelming impression is an air of studied calm. It’s not library quiet, but everybody seems to be working with a scientist’s intensity; it’s a bit like the Q’s workshop in the James Bond films. Unlike previous land-speed record attempts, the Bloodhound project is being run professionally with a (mostly) paid staff, its mission being to increase interest in science and engineering careers in the U.K. and around the world. And after some early financial wobbles it is now fully funded to the end of next year. It’s an expensive business, underwritten by some serious sponsorship. The total budget has risen to £41m—$61 million at current exchange rates and a chunky increase on the $28-million figure we were given in 2012—but still relatively nothing compared to the cost of most cutting-edge aeronautical engineering. “Our budget would not buy you a single system on a modern military jet,” says Chapman.
The team’s entrepreneurial spirit has also helped to keep costs under control, most obviously through the secondment of the RAF technicians, plus four more from the British army’s Royal Electrical and Mechanical Engineer Corps. But also by some high-tech scrounging: The jet engine that will be used in the car is an almost life-expired prototype with just 20 hours of rated life left. “Buying a new one—if you were allowed to—would cost about £4.8 million [$7.2 million],” says Chapman. “The scrap value is about £10,000 [$15,000], and our engine is obviously far closer to that.”
The lack of engine life shouldn’t be an issue, despite the fact it will have to run far beyond its rated maximum speed in the dense ground-level air that Bloodhound will have to digest. (Chapman says, almost as an aside, that the car will have to travel faster than any aircraft has gone at this altitude.) Each run will use the jet engine for 55 seconds, with the rockets firing for just 20 seconds. Even with idling the team estimates the engine will run for less than two hours throughout everything from shakedown testing to the attempts on 1000 mph, which will be done with speed building incrementally over successive runs.
The first time we’ll see the car moving under its own power will be at Newquay airport in Cornwall next month, a former RAF and USAF base, where a 9000-foot runway will allow shakedown runs to be conducted at up to 200 mph. During this trial, Bloodhound will wear conventional aircraft wheels and tires from a 1960s English Electric Lightning jet. Once in the desert it will switch to solid aluminium wheels, built to withstand the enormous stresses of the high-speed runs. Even ‘underspeeding’ by around 10 percent at 1000 mph—they won’t be able to keep up with the rate the ground is passing—they will still be turning at 10,250 rpm.
Perhaps the most exciting thing about the Bloodhound project is the fact that so much of it is going to be shared live, and that it’s the largest STEM (Science, Technology, Engineering and Mathematics) outreach program in the world. The plan is to both stream live video feeds from all the record runs—a TV crew of 100 will be with the car in South Africa—and also to share telemetry. There are 500 sensors on the car, monitoring everything from Green’s heart rate to the exhaust temperatures, with this data being shared both through mobile device apps and, for those keen enough, downloadable data sheets that will, as Andy Chapman puts it, allow anybody to “mark our homework.”
If Bloodhound does succeed in breaking the 1000-mph barrier next year, then the team are confident their record will be exceptionally hard to break. According to Chapman, making a car capable of going substantially quicker would require both advances in materials technology (especially with the design of its wheels), but more important, would also require major improvements in braking.
“It’s easy in principle to put on a bigger rocket and to accelerate faster,” he said. “The problem is that you are relying on aerodynamics to slow the car down. That’s not a problem if you have an infinite length of track, but in Hakseen Pan we’ve found what we think is the largest suitable surface in the world and we’ve only got 12 miles to play with. You could go quicker, there’s always a bigger rocket engine, but that’s going to give you more and more problems when it comes to slowing down.”
Find out more at bloodhoundssc.com.
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