(Note: Since publication of this feature in Professional Engineering Issue 2, 2020, the Bloodhound team announced the project's 'hibernation' due to the Covid-19 pandemic, which is likely to delay the planned 2021 record attempt. We spoke to project CEO Ian Warhurst late last year about the car's successful desert testing, ingenious engineering – and if this is one of the last land speed records as we know it.)
Today, 23 years after Thrust hit 1,228km/h (763mph) and broke the land speed record, Yorkshireman Warhurst is in charge of another British attempt to break the record with Green in the driver’s seat. “I never realised that I was going to be doing what I’m doing,” says the new CEO.
The former owner of turbocharger company Melett stepped in to save the Bloodhound car “from the skip” and give new life to the project at the end of 2018. “I took it on board because I couldn’t believe that after 10 years in the making, and all that money spent on it – and, more importantly, the inspiration the project had given to getting people into engineering – it would just be kind of thrown in the skip, that just didn’t seem right,” he says.
Administrators and the Ministry of Defence were clamouring to secure their assets. “There was a man coming with an angle grinder to cut the car in half,” says Warhurst – military-grade controls were buried deep within the car’s sleek body and could not be otherwise extracted.
The businessman’s timely intervention saved the car from an undignified ending, but the project was still in a perilous state with no remaining sponsors. Further testing was needed before any record attempt, so the CEO made a decision – he would fund high-speed runs in South Africa, doing the “bare minimum” needed to get the car working, while drumming up interest and sponsorship support for a potentially record-breaking return.
The route to the Hakskeen Pan in the Northern Cape was far from smooth. Warhurst reveals he was close to cancelling the trip as the team desperately waited for US approval to use the troublesome military controls. Without the go-ahead, the car effectively had no engines until September, shortly before it left for South Africa. It eventually came through, however.
Creative solutions
Morale is high after the successful trip, in which Green went faster over consecutive runs to eventually reach a top speed of 1,010km/h (628mph) using a Rolls-Royce Eurojet EJ200. The car was truly tested for the first time, vital systems including parachutes and air brakes worked, and a vast network of pressure sensors, accelerometers, GPS units, computers and cameras provided important data for modelling and record attempt planning.
The trip also revealed new challenges under the hot desert sun, inspiring creative engineering solutions.
Testing in the desert threw up problems which took some ingenious solutions to overcome (Credit: Charlie Sperring)
In one run, the engine mysteriously shut down around two- or three-hundred miles an hour. Although Green felt nothing in the cockpit, the shutdown was caused by hitting a slight bump left behind by a regraded causeway running across the track. The engine off switch ‘fluttered’ for just 10ms, but it was enough to kill power. The team tackled the issue by programming a requirement for the switch to be pressed for at least 300ms to cause a shutdown, equivalent to a manual press.
Other solutions were less elegant. After a water tank burst because a cooling water pump was left off, the team decided an expansion tank was needed. With the nearest town two-and-a-half hours away, a branded Bloodhound merchandise bottle was the solution, strapped in place to prevent future blow-outs.
Some fixes were more about brute force. A rear delta underneath the car was sustaining damage and peeling back in a stream of 650km/h mud kicked up by the front wheels. “In good old engineering fashion, the way we fixed it was we put a bigger bit of metal on,” says Warhurst. “Problem solved. Sometimes the simple fixes are the easiest, you know?”
Pushing the boundaries
Despite the challenges thrown up like fine desert dust, the car went faster and faster. Each run was carefully calculated, with a performance meeting assessing the acceleration and deceleration of previous drives and the team agreeing set ‘run profiles’, with speeds to hit and parachute deployments for Green to stick to.
It’s tantalising to wonder if the car could have carried on going faster. Even without the Nammo rocket that will be added to the car before its next runs, Warhurst says the car might have been able to reach record-breaking speeds if it had a bigger fuel tank. One thing stands in the way, however – track length. “We would have liked to have gone faster, except for the fact that we’ve calculated that 1,000km/h, 625mph, was about as fast as we could sensibly go,” says Warhurst.
“If Andy is running down the desert in the car, he’s got two parachutes. If both of them fail, which they did do on a few occasions, then Andy has no way of stopping the car. He can’t touch the foot brake until he gets to 200mph, at which point it’s too late anyway because he’ll then be running off into the stony end of the desert, or beyond… The land speed record is dictated by how long your track is, and we’ve got to the point now where the speeds are so high, you’re covering such a distance in such a short space of time.”
The team had a cleared track of about 19km, enough room to safely accelerate over roughly 10km then decelerate. It is incredibly difficult to find suitably flat and level arenas for the land speed record, even before the back-breaking task of clearing rocks and other obstructions. Drivers would struggle with G-forces in shorter tracks, so options for future projects are severely limited. “I think this is one of the last land speed records as we know it,” says Warhurst. If Bloodhound achieves a new record, perhaps it could stand forever.
With the huge amount of engineering involved, the financial challenges and a shift away from projects seen as not entirely sustainable, the endeavour might look very different in future – an autonomous project, for instance.
“The question there is, would it be as interesting or exciting? No, it wouldn’t, because it’s not just about that, it’s about human endeavour… pushing the boundaries. And that’s what makes it exciting.”
The human endeavour... the Bloodhound team (Credit: Tom McCarthy)
For the record
The project is entirely focused on a record attempt in mid-2021. Warhurst recruits sponsors while engineers such as Dr Ben Evans at the University of Swansea crunch the data from the car, comparing it to computational fluid dynamics models.
Results will determine “how big the rocket needs to be,” informing the work of Nammo in Norway. The rocket will be fed by an electric pump instead of a V8 thanks to advances in electrification. The hydrogen peroxide fed through a silver gauze at
42 l/s will make the rocket ‘zero emissions’, generating thrust by emitting just oxygen and superheated steam.
Small changes might be made to the car before the record attempt, such as winglets on the rear fin – which itself might become smaller to improve grip on the windswept desert plain. But for the first time in a long time, the project seems to be comfortably coasting, with plenty of time to go.
It will return next year to try for a new record, perhaps for the last time – or maybe there will be another Ian Warhurst watching at home, unaware of great things to come.
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.