Happenings

Sonic Boom!

BY Burnpavement

Andy Green, the fastest man alive, tells us more about going supersonic at a recent meet at the Singapore Science Centre.

Wing Commander Andy Green was in town recently to talk about the BLOODHOUND project. We caught up with him at the Singapore Science Centre to find out more about the previous land speed record he has set and the new one that he would be attempting in the BLOODHOUND.

BP: Could you tell us more about your record-setting run in the Thrust SSC back in Oct. 15, 1997?
 
AG: We were at the end of five years of research and development, a huge engineering project. Everybody else had done their bit, and I now had to do mine -- not only get the car through the first measured mile supersonic, but then help the guys turn it around and drive it back supersonic again -- and all within an hour. There were a number of things that had to go right. Quite a lot of those I was influencing. You can find out more on the Thrust SSC website at http://www.thrustssc.com.

BP: So what kind of emotions did you experience inside the car as you finally set the record?

AG: As I came out of the measured mile, through the final timing lights, I knew that we had set the record. However, it’s not over at that point — I’m still travelling at 1,200 km/h and the car needs to stop safely. There’s also a small chance that the timing gear didn’t work — so no celebrations yet. Once the car has stopped, about 10 kilometres and 90 seconds later, the timings come through on the radio — our second run was supersonic and within the required one hour time window, and now we know we’ve done it, time to shut down the car, climb out, and join the celebrations — we’re the world champions!

BP: So why Black Rock to set your original record instead of Bonneville, as we immediately think of the Bonneville Salt Flats for land speed records?

AG: Bonneville has been the ‘home’ of record breaking for 50 years. However, Bonneville is a salt lake, while the Black Rock Desert is a mud playa, which is better for metal-wheeled cars like the Thrust SSC. In addition, Bonneville only had about 15 kilometres of hard surface available, while the Black Rock surface offered over 25 kilometres. Now we have found an even better playa (mud) surface, in the form of the Hakskeen Pan in South Africa, so that is where the BLOODHOUND car will run.

BP: With such speed, how do you keep a ground vehicle from becoming unstable when going supersonic?

AG: That’s the great challenge. Very sophisticated computer modelling is needed to look at the aerodynamics and the car’s handling (suspension and wheels also play a big part in this). Once we have found a solution (for BLOODHOUND SSC it took some five years) then build the car and test it very carefully, step-by-step. It’s a long process, but we’re doing something that a few years ago would have been judged impossible — and we’re sharing our engineering adventure with the whole world, so we’ve got to get it right.

BP: How do you keep the car from physically taking off? Do you use downforce?

AG: As above, it’s very precise aerodynamic modelling, and very precise testing. We need a shape that produces no lift or downforce (too much load would crush the car) — that’s why it took five years to develop the ideal shape for BLOODHOUND.

BP: Having done both, could you compare the sensation of breaking the sound barrier in an aircraft with that in a car?

AG: The car accelerates faster and the ground is much closer!

BP: Last but not the least, could you tell us which skill is more important in breaking a land speed record -- piloting or driving?

AG: For me, the flying skills are about 90% of it, but the other 10%, the driving skills, are important as well — you’ve got to do both.