While Craig Breedlove talks of running his Spirit of America - Sonic Arrow through the Sound Barrier for the first time using remote control, the only simulation with the Castrol-supported Thrust SSC jetcar when it goes supersonic will have taken place back in Britain. After the vital simulation work conducted at Famborough's Defence Research Agency (DRA), England, in recent months, everything else that SSC and its pilot Andy Green does will be completely 'live'.
Since May 1995 Green, a British Royal Air Force Squadron Leader who was selected early last year for duties as the driver of Thrust SSC after an exhaustive series of tests, has been working at the DRA as an Air Defence Advisor. There, in a specially designed simulator, he has clocked up his first 'miles' behind the wheel of the car with which he hopes eventually to set a supersonic land speed record in excess of 750mph (l207kmh).
"In my basic working programme we have eight generic flight simulators which are programmed very, very exactly with all the data of an aircraft: its thrust, its weight, the drag it induces when it turns, the amount of fuel the engines burn. And of course all that varies with height and speed. Then there's its own radar cross-section, its radar detection capability its missile performance, the whole thing."
The systems provide a complete electronic model of an aircraft and its weapon system and its capabilities. It flies precisely like a high-fidelity simulator, with all of the systems linked together to simulate a formation flight, if required. There is one very important extra factor, which is perfect for Green's extra role as the driver of Thrust SSC: though the simulator is computer-driven, there is a requirement for manual input. A man must actually control the overall system, and he is as fallible as he would be in the real thing.
"It's called Man-in-the-Loop," Green explains. "That is the essence of the system we call the JOUST simulation. It's one of the few simulators in Europe set up that way and doing this level of work. You start off with a new concept, a new aircraft, or a new missile, and rather than just programming something into the system and seeing how it will work, we can actually fly it with people such as myself The pilot will use the strengths and weaknesses of his aeroplane and equipment as effectively as possible."
Even without the SSC simulator, this would be perfect for keeping his hand in as he awaits completion of the giant 54 foot (16.4 metre) long ground missile that he will drive into the history books. "It is surprising how good all this training is for that," he reveals.
The SSC simulator has been designed by Farnborough's Systems Integration facility using this JOUST technology Green has 'driven' this highly sophisticated piece of equipment several times, but has been careful not to become over-familiar.
"The problem with over-training on a simulator is that you end up training yourself for the simulator rather than training yourself for the real thing," he cautions. The simulator is currently being upgraded even further, for the work done on it so far has enabled Green and the Thrust team to come up with the final design of SSC's cockpit layout. "We also have some more data on the exact weights and moments of inertia and engine thrusts, rather than the first estimates that we had, so we are now making a much higher fidelity model within the simulator. Once all that is programmed in I shall do more training on that."
He still vividly remembers his first experience of the task ahead, when he tried the simulator for the first time.
"I was absolutely overawed by the speed. I could not believe how quickly it accelerated, even without using the afterburner. The great benefit of it is that, having done it five or six times, I very rapidly started to see the pattern. It accelerates really quickly and I've got to watch this, this and this, and I put the afterburner in here, so look at this and this. And very quickly you start to see the pace at which things happen, and the pace I've got to respond. The first time I was just way, way behind it. It's just the same with flying an aircraft simulator the first time you get in. Despite the fact that you've been trained on all the systems, you get in and you're just way behind because it's all happened so quickly And then once you've practiced it a few times you very rapidly begin to catch up. The tremendous benefit of having something like this available for training, is that there is so much to assimilate and it helps you to do that."
The other key element is that the simulator has a technical research function, too. Aerodynamics designer Ron Ayers has run all the datasheets on the performance of the car, and been able to cross check them with the simulator because it's using all the same data, albeit all arrived at using a completely different set of calculations. Encouragingly, he has seen the two approaches coming out with exactly the same set of figures just as, at a key stage of the project's early days, computational fluid dynamics technology was able to verify data. This was acquired while running a scale model of Thrust SSC on a rocket-powered sled up to speeds of 850mph (1 368kmh) at the Proof and Experimental Establishment at Pendine, which was funded by Castrol.
This technological data match is just one more factor that fills Green with enormous confidence, not only in the ability of Thrust SSC to fulfill its aim, but in the basic integrity of the project and the people behind it.
"It's the fact that even when Ron has all this brilliant proof, he says that he isn't going to accept any of it. His attitude remains: 'We think we know what's happening, but now let's actually go out and do a proper investigation using the car.' The team is cautious and tremendously professional in its attitude, which just gives me a feeling of confidence, both in the research it has already done, and the way that it is approaching running the car in the future. We have, after all, taken a major step away from anything that has been done in the past where people build minimalist cars with the minimum number of systems and the maximum amount of thrust and minimum drag, see how fast it can go, and hope they have the design right and that it stays stuck to the ground. We have actually gone completely the other way and said we are going to build a completely safe car - what is the level of technology that we need to achieve the record safely? Right, now how are we going to make that go really fast?"
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