From the July 2015 issue
The land speed record has long been a curiously British obsession. Since it was first set back in 1898, when Frenchman Gaston de Chasseloup-Laubat drove his electric Jeantaud to a dizzying 39 mph, Brits have held the title to the fastest land vehicle on earth for a combined 75 years (the U.S. comes second with 28 years). It was a British car that took the record supersonic, when ThrustSSC hit 763 mph in 1997 and broke the sound barrier. And now an even more powerful challenger is being readied in a nondescript industrial warehouse near Bristol.
Bloodhound SSC—SSC for “supersonic car”—will use both jet and rocket power in its record-setting attempts. Following a 200-mph test run in the summer, the team will target 800 mph later this year and 1000 mph in 2016. The venue will be a specially prepared 12-mile-long course on the Hakseen Pan, a salt flat in South Africa. Royal Air Force Wing Commander Andy Green, the man who drove ThrustSSC, will also be piloting Bloodhound, meaning there will be the most experience possible in the cockpit. He’s as unflappable as you’d expect an RAF pilot to be, but he acknowledges that, despite extensive computer modeling, he will be taking a trip into the unknown.
Unlike most previous land speed record attempts, Bloodhound is a professional project, fully funded by sponsors and charged with the mission of increasing interest in engineering and science in the U.K. and around the world. To that end, the car’s blueprints are being shared online, and all record attempts will be streamed live around the world, using 500 channels of telemetry data from the car.
1. Car
It’s 44 feet long, 9 feet tall at the fin, and will weigh 8.6 tons when fully fueled, but Bloodhound is a relative minnow compared with ThrustSSC, which was 10 feet longer and two tons heavier.
2. Wheels
The wheels aren’t powered, but to take the land speed record, Bloodhound needs what will be the fastest set of wheels ever produced. These are made from solid aluminum and will rotate at 10,200 rpm. At 1000 mph, they’ll turn about 10 percent slower than the car is traveling because of slip.
3. Cockpit
During the record runs, Bloodhound’s cockpit will become one of the loudest places on earth, as it sits directly below the jet engine’s air intake. It’s surrounded by thick soundproofing. All cockpit data is presented with color-coded bars on display monitors.
4. Steering
Bloodhound SSC uses conventional steering gear. ThrustSSC’s twin jet engines meant it used rear steering, which Andy Green remembers as “alarmingly wayward.” Fortunately for him, Bloodhound steers with its front wheels. Steering characteristics will change dramatically at speed, with supersonic shock waves making it hypersensitive above 700 mph.
5. Air Intake
One of the biggest engineering challenges here is slowing down the airflow enough for the jet engine to digest it. With the car traveling at 1000 mph, the air will have to lose 400 mph of velocity in the intake cowling. Bloodhound will be faster than any jet aircraft has operated at low altitude.
6. Oxidizer Engine
Delivering the high-test peroxide to the rocket motors [see: “Rockets”] requires a serious pump. The original plan was to use a Cosworth F1 engine; the new scheme calls for a 5.0-liter supercharged Jaguar V-8 producing 800 horsepower.
7. Jet Engine
Primary power comes from a Rolls-Royce EJ200 jet engine, more normally fitted to a Eurofighter Typhoon fighter jet, producing 20,000 pounds of thrust. The actual engine is a prototype with just 20 hours of use left, but that’s plenty. Each of Bloodhound’s record runs will be under 120 seconds.
8. Rockets
The jet engine’s reduced efficiency at higher speeds means the car also needs rocket power. Each rocket, produced by the Norwegian company Nammo, delivers an additional 27,500 pounds of thrust and uses solid fuel with high-test peroxide as a liquid oxidizer for a 20-second burn. A single rocket will be used for the 800-mph target run; a cluster of three will chase 1000 mph.
1. Brakes and Parachutes
You won’t be surprised to learn that Bloodhound has multiple means of stopping. Just cutting the engines at 1000 mph will produce 3.0 g’s of deceleration. Air brakes will be deployed at around 700 mph, and there are two backup parachutes. Hydraulic brakes with carbon-ceramic discs will be used below 200 mph.
2. Wings
The tail fin and rear wings aid stability and will operate automatically. The wings trim Bloodhound to be lift-neutral. Ride height at speed will be just 3.1 inches above the salt.
The Record
The FIA states that the land speed record is set by a two-way average through a measured mile achieved within one hour. The “turnaround team” that will refuel and re-prepare the car is aiming to be ready to send it off the second time within 45 minutes.
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