Outrunning
Outrunning
sound
Why land speed record holder Noble is building Thrust SSC to challenge Mdaren in a race to the Sound Barrier on land and why he won’t be at the himself this time
Richard Noble has some new bedtime reading. Not for him something by Salman Rushdie, Gilly Cooper or Alan Clark. Just before he turns in each night, he prefers a line or two from
the Lockheed SR-7l flight manual. Yes, that’s the famed Blackbird . . .
. . .
We are in his sitting room. Laid casually on the floor is £30,000 worth of strain gauge balance, with what looks not unlike the Blackbird attached to one end. Closer inspection reveals a lack of wings, bar a vestigial tailplane. Whatever it is, it looks quick. Noble knows it is, for this very creation has already travelled at Mach 1.1.
This is a gorgeous aluminium model of Thrust SSC, the car he believes will break the Sound Barrier. A video plays footage of the model on test on a rocket sled in Pendine, south Wales, upon whose sands the record used to fall in the mid-1920s and where Parry Thomas perished back in 1927 trying to beat 180mph. Noble is, as usual, in full spate. It hasn’t struck me before, but now 1 see a resemblance to the Labour MR lack Cunningham, as he speaks.
Perhaps I watch theperformance with more than my usual amount of cynical detachment. But you don’t listen long before you are impressed in spite of yourself. And your mind’s eye is full of laughter at various points as he unravels a tale that could only be. . .well, which could only be Richard Noble and Thrust.
We’ve been here before, I keep reminding myself. With Thrust 2, and with the battle against the world’s scepticism about a public school-educated bloke with a jet engine in his garage and a dream to smash the land speed record.
This time around a lot of things are different, though The speed, for a start. It’s not 622.407mph to beat. Noble erased Gary Gabelich’s 1970 mark with his own record at Nevada’s Black Rock Desert on October 4 1983. But he’s not interested remotely in his own 633.468 figure, either. Last time out the aim was 650, which Thrust 2 peaked at on its record run. This time it’s 850, well past the speed of sound.
This time, too, there is real competition. With Thrust 2 there were always spectres in the background, but this time there really is McLaren. There really is Craig Breedlove. Both, like Thrust SSC, are near to build.
And this time there is less angst about finance. True, it may not be in McLaren’s perceived league, and there may have to be shortcuts, but being the holder of the title of Fastest Man on Earth has to count for something, and Noble exudes the confident air of one who knows that there are companies waiting on the sidelines to throw their cash into a kitty already boosted by Castrol and TI Group.
Oh, and this time there isn’t a jet engine in the garage. No, not one. There are four, two racers and two spares… We always knew that Thrust 3 existed in designer John Ackroyd’s head, and that he and Noble had tossed some ideas around a
long while ago, because Thrust 2 was initially only ever intended as a show car until its wind tunnel tests at Weybridge proved so positive that it became the record attempt vehicle. But Noble and Ackers had grown apart when Noble began to sense what McLaren was planning with its Maverick project.
It was a sensitive time for him. He was no longer involved with the ARV light aircraft project which he had founded the year after breaking the land speed record, and he was just realising that his Atlantic Sprinter transatlantic crossing venture would have to go into liquidation. As he said, an ’80s project had dragged into the ’90s.
He needed something exciting to do, and another crack at the lsr could not have come at a better time. The major problem, however, was his awareness of just how close Thrust 2 had been to the edge on its record run.
“You remember the graph of the loading on the front suspension . . . Frankly that was horrendous! It scared the hell out of me and it scared the hell out of Ackers! We think Thrust 2 could have gone about point one Mach, about seven miles an hour, faster before the front end started lifting. .”
Noble acknowledges that a sizeable reason for that was that Thrust 2 was deliberately run with positive pitch on its final outing. to take some of the weight off the front end in order to reduce rolling resistance on a surface that was neither as dry nor as hard as ideally it might have been.
But therein nevertheless lay one of the problems. Thrust 2 was never intended to be a research vehicle, so neither he nor Ackroyd could be absolutely sure just what the rolling resistance was. Worse, from the point of view of chasing a supersonic record, nobody knew what happened beneath such a projectile. Without solving these twin problems, there was no way forward.
In the end Ackers headed to Reno to continue his balloon projects, but Noble had a chance meeting with Ron Ayers, the chief aerodynamicist at BAC on the Bloodhound missile and a keen technical student of Isr cars. His pet theory was that all of them had in some way underperformed, and he and Noble set out on separate paths to find out why.
“Ron was very interested, and so was I, that there was always a 4000Ib thrust difference in what might have been the power of the Avon engine in Thrust 2 and what effectively might have been the aerodynamic drag. Was all that power absorbed by the rolling resistance of the Black Rock Desert? “It took us two and a half months. It’s terribly difficult to do, and we both decided to approach it using different methods. You could only do this sort of thing empirically. We took the data that we had and tried to reconstitute it mathematically and also to apply some sort of sensible logic to the thing. Eventually we got there and we ended up with a situation where we believe that we knew what happened to Thrust 2, we came
up with a considered opinion what the thrust was, we came up with a considered opinion what the actual roll drag was, and from that we calculated the rolling resistance, and from each stage therefore we were able to calculate the rolling resistance and also the relationship between the rolling resistance and the speed, which of course is crucial.”
With that done, they started reconsidering the early conceptual ideas for the third Thrust, but both soon concluded that they’d got to look at something completely different. Thus was born Thrust SSC, but not until they realised the true facts behind cross-sectional area.
Conventional wisdom, since the days of Gabelich’s Blue Flame in the very late ’60s, had suggested that a Vee-bottom, pencilslim hull was best for aspiring supersonic cars, to help bounce away any harmful shockwaves. Ever since, that sort of dogma has held true, even though to date the Budweiser Rocket is the only car to claim to have gone supersonic (and it is extremely doubtful that it did).
In a nutshell, the cross-sectional area rule favours twin-engined designs, because you don’t have to count the filament of air that runs through the exposed jet. According to Noble, “When you actually do your sums what you see therefore is that the thrust per unit area is a hell of a sight greater. It’s a factor of about 30 percent.”
They also realised that they’d got to have a really enormous amount of power, and that an ordinary turbojet, whose thrust drops or at least levels off the faster the vehicle goes, would not be enough. They needed something with an element of bypass, half turbojet, half ram-jet.
At this stage in the rather one-sided conversation, Noble gestures towards the drawings for Thrust SSC. His speech is rapid-fire, the arms move a lot, he shifts around in his seat all the time. It’s all purely unconscious, but it’s as if he’s back doing a presentation to a potential sponsor. You remind yourself for the umpteenth time why he has been so successful raising backing in the past. SSC is effectively Thrust 2 turned inside out. Instead of a cockpit either side of a jet engine, it is two jet engines either side of a cockpit. The whole thing is held together by
a reverse tricycle backbone spaceframe chassis on which the front wheels are widely spaced and the rears are mounted in tandem like the Summers’ Brothers old Pollywog streamliner. It’s all clothed in a mix of carbon fibre (for the engine nacelles), aluminium and stainless steel. At 54 feet in length and weighing seven tons, it’s the biggest lsr car ever, and arguably the most dramatic looking.
Listen to Noble and the sheer logic of the design process becomes fascinating. Ever since I’ve know him he’s always been a proponent of having the centre of gravity of a record vehicle as far forward as possible, and the centre of aerodynamic pressure as far back. The Rolls-Royce Spey engines he will use are heavy, massively powerful and long, but they enable him and Ayers to do exactly what they want. Mounted either side of the cockpit, they get the cg way up front, while the extended tail brings the cp back accordingly. Their criteria for aerodynamic and dynamic stability are satisfied. The roll resistance is good too, because the front wheels are tucked away in the nacelles. But isn’t there a problem steering them in that position? You already know the answer, but it’s interesting to see the effect the question has. I’d swear Noble rubs his hands as he launches into another speech about rear-wheel steering, the brainchild of Glynne Bowsher. The latter is a quiet, selfeffacing Welshman who was part of the old Thrust team when he looked after Thrust 2’s brakes. Now he’s been drawn from his shell, and as well as designing all-new L77 aluminium alloy wheels which are bigger and stronger than 2’s, he’s done the spaceframe chassis and suggested the solution to obviate the problem of getting
the front wheels to turn in the restricted space within the engine nacelles. When Bowsher first mooted rear-wheel steering, Noble admits that he was highly sceptical. “I said, ‘Glynne, we’ll never, never persuade people that this is viable! I mean everyone is used to airport trolleys that go out of control, dumper trucks… And I said. ‘Well, look Glynne, we’re going way outside… We can’t convince people. I’m not convinced
After Bowsher had cannibalised his brother-in-law’s Mini, locked the front wheels and added rear-wheel steering via a special spaceframe welded to the rear end, however, tests at MIRA convinced him.
“We discovered after the first runs that there there was a slight bit of slip in the linkage, and we tightened that up, and from that moment on it was absolutely magic! We could hare down the straights at 90, and we could go hands off, absolutely straight. It’s very, very accurate. You can position it absolutely on the line and hold it on the line the whole way down the track.” All through the past two years it is quite clear that Noble and Ayers have pushed down every avenue of research possible. to ensure the credibility and feasibility of their vehicle, and he admits that there were several hiatuses at which the project appeared set to stumble. “We took the firm decision that you cannot go ahead really you must not go ahead with any project where there is real doubt about the vehicle’s effective ability to do it,” he says trenchantly. Each time, however, they came up with some form of solution. Nothing epitomises that better than the tests at Pendine. at the MoD’s Proof and Expenmental Establishment rocket sled facility,
where they actually conducted their aerodynamic testing at real speeds. Noble, quite rightly, is very pleased with this bit of lateral thinking, and seems even more like an excited schoolboy as he relates the tale.
With what seed capital they had not a huge amount but significantly more than the £175 with which they started the Thrust 2 project back in 1977 they liaised with Imperial College and University College of Swansea and used their computational fluid dynamics to come up with behavioural predictions for the car, but the problem with cfd is precisely that it is computer figures. “You get very nice pictures, but then you say, ‘Hang on, can we really believe this? How can we prove this? This is what it says, but is it believable?”
As you might imagine, wind tunnels suitable for supersonic cars are rarer than credible politicians, no doubt because there have not yet been any supersonic cars to make use of them. It’s not a market one can envisage booming. There are plenty that run up to 100mph with moving ground boards, and their figures can be extrapolated with a high degree of accuracy for speeds up to around 250nnph. It’s different when you start talking about 850.
Hence Noble’s stroke of pure genius in approaching Colonel Lowry at Pendine.
“You know, that rocket railway is absolutely amazing. It comprises two sections of British Rail track, 1.6 kilometres long. The accuracy of this is point six of a millimetre in 1.6 kilometres. It’s absolutely staggering. The sled there has 18 rockets to accelerate it and four to decelerate it. It goes nought to 880mph in one second and pulls 50G off the line!
“What they use it for, largely, is zapping bombs down the track and into great lumps of concrete. And they come off the end at basically three times the speed of sound. So we thought that if we built a sledge, which basically gripped the outside edge of the rail, then we could fill the inside of the rail UP with a road, instrument our model and mount it on a strain gauge balance, use the telemetry off the sled, and then get our readings …” It worked. An extremely sophisticated model was built by G-Force Precision Engineering in Fontwell (formerly Ganassi Racing’s UK offshoot) and with it strapped to
the strain gauge balance they were able to obtain readings at the critical speeds over 800mph (the model has so far run to Mach 1.1), but also get all the speeds either side, up and down. They then ran the film they shot on a clear wall and were able to calculate precisely what pitch deviations were experienced by the model.
This led to another crunch point, when the rocket sled findings had to be compared with the cfd figures. “The problem was, if they didn’t match up, we couldn’t believe either of them . . .” But they did. “So then we knew exactly what happens underneath the car.”
Thus were the elements of Thrust SSC finally coming together. Like McLaren’s rival Maverick, Noble’s new machine will rely totally on active suspension, and a system is already well advanced at the Flight Systems and Measurements Laboratories at the College of Aeronautics at Cranfield. “You’re looking at enormous forces. You’re dealing with a lift slope of the order of 5G per degree. So in other words, one degree up in incidence leads to a 5G vertical load, or 5G the other way,” reminds Noble, “and you’ve got to control the pitch absolutely accurately. Certainly, our system is considerably simpler than a Grand Prix installation. It simply has to be active, you’ve got to control that pitch and you’ve got to control the loading on the car.”
The last big hurdle has been the power units, but just like Thrust 1 and Thrust 2, the story of Thrust SSC is already littered with examples of supreme opportunism. RollsRoyce’s relationship with McLaren precluded any dialogue, but then by the sort of convoluted but undoubtedly fated process one historically associates with Thrust, they came across a brace of Rolls-Royce Speys. “Originally we looked at the RBI 99, it seemed to be the sensible engine. Obviously that’s why McLaren went down the same route. It’s a very nice little engine, three spool, very light, good power to weight ratio. All that’s extremely good. The downside is that II it needs a separate gearbox so you’ve got quite a lot of installation problems, and 2) it’s a computer-driven engine, so you’ve got that side of it. You can control your engine absolutely, and make it do exactly what you want, but the downside is that there’s a lot of software that’s got to be
written, and you’ve got to experiment with it. And we wanted really a fit and forget engine.”
He was also worried about the effect of a dusty desert atmosphere on the finely engineered cooling holes in the turbine blades.
“And the other thing too is that it’s a very short engine. What you want with these supersonic vehicles, long, thin Concordelike vehicles, you’ve got to get a really long, long shape to it. And this becomes difficult when you’re faced with an engine which is actually very short, because while it’s great to stick in the back of a Tornado, if you try putting it in a nacelle like ours here, it just doesn’t work. Our nacelles are 20-odd feet long. The car is over 50 feet long. Two Thrust 2s.
“So that made us think. As far as RollsRoyce is concerned, I don’t even talk to them because they’re involved with Ron.
They’re plastered all over his car. This is the published fact that we’ve heard.
“So in the middle of all this I was talking to my various friends in the Air Force about what the hell we were going to do, and they said: ‘Well, there’s always the Spey.’ We said, ‘Oh God, not a Spey!’ You know, a 1960s engine, a huge great heavy thing. Bloody massive. They claimed 20,000 lbs of thrust, but it was probably closer to 19,000 on the test bed. So, no.
“And then somebody said, ‘Well, there is the Spey 205.’ I only knew of the 202, what was the 205? This was a very expensive project undertaken by the Ministry of Defence, to extend the hot-end life, of the Spey 202. Basically the engine could be uprated for a longer life or increase in performance. So, one thing led to another, and somewhere along the line we managed to acquire two of the 205s, still in their Rolls-Royce wrappings.” That is typical Thrust luck! “I understand there were only 12 built. Those engines never actually flew, it was part of the programme which was coming to fruition when basically the Phantom was scrapped, and that was it. We were lucky enough to get those two, plus two 202s, and we then managed to get talking to the various people involved in the 205 programme, to find out just how much they could be uprated to. They reckon 25,000 lbs of thrust apiece…”
Ask who will drive Thrust SSC, and for the first time Noble becomes noticeably edgy.
Again, you already know the answer, but are interested to see how he frames it. The voice becomes more clipped, the sentences sharper. The bonhomie is missing from his tone. This is the manner Noble reserves for dealing with Bad Things, and for once, he does not come across very convincingly. He glances at his wife.
“We’re in a difficult situation. There are a number of problems. Obviously, Sally is not very enthusiastic, point one. Point two is that we’re into a situation where, in order to get the car operational by next year, we’ve got to go for one hell of a build operation. Basically, to fund that and to manage that is going to be a hell of an undertaking. We’re going to be right back where we were with Thrust 2. Do you remember when we arrived at Bonneville in 1981 we were all absolutely shattered and in no condition. No element of driver training whatsoever. We were just very thankful that we’d managed to get our half completed car to the desert. We’ve got to get on with it, we can’t afford that sort of situation.
“My situation is that I’ve made a very, very painful decision. The reality is that we’ve got to find somebody who has got to live with the team, who has got to actually train up with the team, and who will then become the car’s driver. This is the role of a minor test pilot. I mean, in Thrust 2 what were we doing? What it requires is somebody who is quite happy at dealing with high speeds. The ability, basically, to process an enormous amount of information under stress and under pressure, extreme pressure . . .”
The voice trails off a little as Noble relives the past. “I can still remember those runs as if they were yesterday. You remember the mark the timekeepers made across the measured mile? I can still remember going over that at 650. Seeing all those polygons going underneath. You could see every single detail. And principally that’s because effectively what had happened is like an accident, where your mental processes have speeded up to such a point that the whole thing is a very relaxed, slow motion effort. That’s what you’ve got to get.
“The other side of it is the disciplines. I mean, the car is a low-flying aeroplane, effectively. You’ve got to therefore have people with aeroplane experience and aeroplane skill. Yeah, it’s a minor test pilot’s role. I think that’s right.” Without Dr Brian Ridgewell, International Marketing and Technology Director at Castrol, it’s doubtful that Thrust SSC would ever have gone beyond the paper stage. Noble was invited to address the conference of managing directors in Palm Springs that Castrol promotes every five years, and his theme was the land speed record. He took personnel at their word when they advised him that they would come aboard if he ever considered having another go, and ulti
mately, Ridgewell released £40,000 to fund the research programme.
If there is one thing Noble understands more than anything else, it is the value of money. “You know, Brian’s decision was extraordinarily courageous. It takes real guts to take a corporate gamble like that…”
Following completion of the research Castrol has advanced a lot more money, while TI Group, which built the spaceframe and supplied its materials for Thrust 2, has also pledged further support. Others seem imminent. “We’ve started going out and talking to people, and the response is fantastic!” Noble smirks happily. “I mean, you think back to the Thrust 2 days and think how difficult it was, how everyone was very negative and how long it took, now it seems what’s happened is people are looking for something al exciting and 131 something
that’s very different.”
Building commenced in mid-June, and he is aiming to be on the Black Rock Desert next September, which means a very tight schedule. Ever a realist, he says, “Everything is controlled by cash, as we all know. But I think that’s what we’ve got to do. Breedlove’s on the way, so is McLaren. We’ve got to get out to Black Rock next year, and we’ve got to be in the Mach 0.9s.”
He is also open about the speed he’s looking for: like McLaren he talks not of 750, but 850 by 1996. “We can’t sort of hang around at Mach 1; we’ve got to go a lot faster than that. Because at these speeds, around Mach I , what you’ve got is a nasty sort of mix of airflows which are subsonic and supersonic, so what’s actually happening is that you’ve got this nasty mix but a very small increment pushes that subsonic airflow supersonic and everything sort of settles down and smoothes out. It a very nice thing to handle.”
He pauses briefly as he thinks of another point. For anyone taking written notes it must be the equivalent of momentary cessation of machine gun fire. “I think the sensible thing for everybody, basically, to do would be to run on both of the available venues,” he says. “Black Rock and Lake Gairdner in Australia. What it means is that you could develop the car in two different seasons, at two different times in the same financial year. Now that is terrific, instead of the awful problem we had with Thrust 2. which was slog away for a year and get the car out for 40 days running, and then hit the weather, . .”
As Rosco McGlashan prepares to push after Noble’s 633.468mph mark with his transonic Aussie Invader II, he knows that there are three serious supersonic contenders starting to construct their designs Breedlove, McLaren and now Noble. The Sound Barrier on land will not just be a fantastic achievement for the first man to breach it it’s become a race as well. D J T If you are interested in joining Thrust, write to The Mach I Club, PO Box 77, Twickenham TWI2 2XN.