You had a glittering career as an engineer. How did that lead to your involvement in land-speed record bids?
After I’d retired in the early 1990s, I started volunteering at the Brooklands motorsport and aviation museum in Surrey. When I went into the archives there, I came across a huge wall of wind-tunnel reports for Vickers and other aircraft-makers, going back to the early 1930s and before. As a qualified aerodynamicist, seeing that amount of historical data, well, it was like being in a goldmine.
While cataloguing the material, I also found wind-tunnel data on cars that had been running around the Brooklands race track. This included material on all the land-speed record machines – Malcolm Campbell’s Bluebird cars, the Golden Arrow, the Silver Bullet, the Thunderbolt. They had all been wind-tunnel tested at Brooklands.
I found that the numbers didn’t stack up – the cars had underperformed relative to their original design specifications. My theoretical predictions made using that aerodynamic data showed that the cars should have gone faster. The discrepancy started at about 200mph, and the faster they went, the greater the discrepancy. I was at a loss to know why. That sparked my interest in land-speed records.
How did you get involved with Richard Noble on the Thrust SSC project?
I wanted to get more data to support my research. So I went to see Ken Norris, who had designed Donald Campbell’s Bluebird. I was late for the meeting and that meant I overlapped with Richard Noble, who was a personal friend of Ken. It was a pure chance encounter. When Richard heard that I specialised in high-speed aerodynamics I could see his mind working. And that was that.
What did you think of Noble’s plan to build a car capable of shattering the land-speed record?
When he told me he wanted to go supersonic, I said “don’t be ridiculous, it’s impossible, you will never keep the car on the ground”. But two or three months later, I got thinking – some of the reasons I gave for it being impossible weren’t strictly true. I had told him that shock waves forced under the car would lift up the nose, sending it straight up. But what if we really stuck the tail of the vehicle up in the air? I knew forces would push it down – so there had to be an angle at which it wouldn’t lift up because there would be a zero vertical force. On that logic, I knew it was conceivable that you could have a supersonic car that stayed on the ground. I telephoned Richard and admitted that what I’d told him wasn’t quite true. That was it – “right, we’ll do it then”, he said.
What were the biggest challenges?
I decided early on that the car would be better off with two jet engines rather than one. But then we had to work out how we were going to do that. Should we have the engines on top of each other? Maybe, but that would give stability problems. We played plenty of games like that.
I decided to put the engines side-by-side, but wanted to put them well forward. That introduced severe problems, because it meant the front wheels couldn’t be steered because they were outboard of all the structure. So we had to steer the rear wheels. That introduced other problems. Rear-wheel steering is theoretically unstable, partly because of the mathematics of it and partly because of physiology. When you turn to go left, your stomach goes right, and so you have to train yourself to overcome that.
We referred the matter to the late Professor David Crolla, vehicle dynamics expert at the University of Leeds, and we did a lot of research on rear-wheel steering. Eventually, we kind of made it work. But in truth, it was a close call in terms of whether it was good enough. It was a credit to Thrust SSC driver Andy Green, who has the most astonishing reflexes, ensuring the car stayed stable.
It sounds like you had to think laterally to overcome many technical difficulties. Was there ever a time on Thrust when you thought, privately, “this is crazy, it’s never going to work”?
Plenty of times I thought “This is crazy, we will never get the money to complete the project.” But I don’t think there was ever a time when I gave up on the technology. I always thought we’d make it work. But it was a trouble keeping the team together and keeping the sponsors behind us.
Thrust broke the land-speed record, achieving 763mph, and was the first car to go past the sound barrier. How did it feel when it all came together?
It was a mixture of relief, exultation and exhaustion. Myself and a few colleagues were positioned at the start of the course in the Black Rock Desert in Nevada, and when the car did its run we were left totally alone in the wide open space. When we realised it had achieved its goal, there was great exhilaration.
We drove the 14 miles to the finish line, and there we found the car surrounded by people. The desert had filled up – it was a scene of almost biblical proportions. There was our team, hundreds of press, people landing on the desert in light aircraft, people who had been parked up overlooking the event, crowds coming from everywhere. It was a scene of euphoric celebration. There were people wandering around in tears, saying “This is the greatest day of my life – I’ve seen history in the making.” At that point, you couldn’t fail to be excited.
You were also a prime figure on the JCB Dieselmax project, which achieved a land-speed record for a diesel vehicle. Presumably that presented a very different set of challenges from Thrust?
That was the first time I had been involved in a wheel-driven record attempt, as opposed to a jet-driven vehicle. It was a different art form. But actually, Dieselmax proved to be the point at which my museum work really came in useful.
From looking at why land-speed record cars had not achieved maximum speed, I had arrived at a theory: the cars kicked up so much dust and salt crystals, which was blasted over the rest of the vehicle, that they had suffered from “spray” drag. The rear wheels were
getting absolutely covered. That’s what I deduced was going on.
So when I started on Dieselmax, I said to the people on the design team that I wanted to do an experiment on the shape of the car. The weight of the engines meant the centre of gravity had to be low, meaning the car had to be very close to the ground. I looked at ways of channelling air more efficiently from under the car, avoiding the accumulation of salt crystals on the underside. Two channels were created, so that the air could get through and out again.
It worked well. Dieselmax was designed to reach around 350mph. But if the tyres had allowed it, we could have gone up to 380mph. I had proved my point – that with the right kind of design, the problem could be overcome.