Bloodhound land speed car will be back racing next week

By Jonathan Amos
BBC Science Correspondent, Hakskeen Pan, South Africa

Image caption,
The upper-chassis was lifted off to one side of the car

The Bloodhound land speed challenger is likely to be back out on its South African lakebed track early next week.

Engineers are now satisfied they understand why a heat alarm has been triggering on the car when it runs.

Bloodhound was in the middle of trying to post a speed of 550mph (885km/h) on Friday when the sensor system alerted driver Andy Green that temperatures might be too high in the engine bay.

He aborted, pulling up early having reached only 481mph (774km/h).

Something similar occurred on Wednesday as well, although right at the end of the run when the vehicle was slowing down.

But by Saturday afternoon, the British Bloodhound team had split open the upper-chassis of the car for inspection, including of that troublesome sensor, and concluded there was nothing seriously awry.

Known as a "firewire", the sensor is essentially two parallel wires running through a plastic sheath.

This wiring criss-crosses the engine bay. When it gets too hot, the plastic melts and the two metal cores touch, triggering the alarm.

Engineers could find sections of firewire that had bubbled and warped, indicating they had experienced heating, but separate temperature strips in the bay revealed that nothing had approached the level of a fire risk.

Media caption,
Watch the Bloodhound supercar get off the line

Chief engineer Mark Chapman told BBC News: "The temperature stickers on the walls of the bay tell us it wasn't really hot enough in there that firewire would normally trigger. So, it's possible there may have been some local heating, but it could be as simple as the firewire touching the hot engine casing. We'll replace it and then get back out there."

Wednesday looks to be the next day of running.

Image caption,
The firewire quite likely came into contact with the hot engine casing

Bloodhound has been steadily winding up its speed here on Hakskeen Pan as it works towards a challenge on the land speed record in 12 or 18 months' time.

Its fastest outing so far was on Wednesday when it posted 501mph (806km/h). This is a long way short of the all time record of 763mph (1,228km/h) set 22 years ago, but Bloodhound is currently still operating well within its performance limits.

Its Rolls-Royce EJ200 Eurofighter engine should be capable of pushing the car beyond 600mph (965km/h), and with the coming addition of a rocket motor from the Norwegian Nammo company - a top speed of more than 800mph (1,287km/h) ought to be a realistic goal.

Image caption,
Removing the Eurofighter engine made space for other fixes

Bloodhound team owner Ian Warhurst is relieved Saturday's inspection didn't throw up anything serious. And while splitting open the upper-chassis is no easy task, he says it's allowed engineers to fix one or two other technical niggles as well.

"The systems guys can dig in deep; they've got all sorts of things they've been desperate to do. And we haven't been getting data from the right-rear suspension. There are computer boxes in that corner we just couldn't get to without taking the top off. We can now," the Yorkshire businessman said.

Image caption,
The run planning desk: Bloodhound has been increasing its speed in 50mph increments

The Bloodhound team arrived in the Kalahari Desert in mid-October and probably has another couple of weeks of testing before packing up for the season.

Next week will see the car try once again to post a 550mph, followed by a 600mph.

To some extent, the top speed this year is irrelevant; what's more important is that the team leaves Hakskeen Pan with the data to validate its design models and that driver Andy Green is attuned to - and comfortable with - Bloodhound's handling.

All this would be seen as very sound progress.

But it would be great also to lay down a marker for the future.

Image caption,
Friday saw driver Andy Green abort the day's run early

Only seven vehicles in the history of the land speed record have raced above 600mph: Sonic 1, Blue Flame, Thrust2, Budweiser Rocket, Sonic Arrow, Aussie Invader III; and Thrust SSC, the current record holder.

A 621mph would be a nice-to-have here on the Pan before going home. It's a pleasant round 1,000km/h.

"I'm well aware of that," said Ian Warhurst with a grin on his face.

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