It has been a frustrating week. After finally getting a day’s break (please see A Grand Day Out for details) from the unrelenting pressure of the project after Saturday’s two runs to a peak of 330mph, the engineering team returned on Monday to prepare ThrustSSC for more action. As well as any changes required as a result of the design team’s analyses from the previous day, the car would be checked over for any problems.
Almost immediately a fault was found in the steering system - to diagnose it the team would have to take down one of the forged-aluminium rear wheels and its supporting strut. Together with any work required to fix the problem and reassembly of the various parts, it was not something that could be fixed in one day - Tuesday’s planned run to 400mph would have to be postponed.
As it transpired, the fault when identified was a relatively easy one to fix, but a bearing showed signs of damage and replacing it prolonged the work. Tuesday went by - with good running weather lost. Tuesday night, however, the heavens opened and soaked the desert to the extent that the surface became a mud-bath. Faces were long - it was not supposed to rain like this for another month.
The Jafr Desert has been full of surprises for the team, and this was no exception. By mid-morning on Wednesday the surface was once again hard, albeit slightly softer from the moisture that had soaked in. In many ways, it was a blessing - not only did it lay the appalling dust that has been playing havoc with equipment, but the softer surface was in fact much closer to that envisaged in the design of the car. Paradoxically, the increased rolling resistance could well increase the maximum speed that could safely be achieved in Jordan - in a "worst case" scenario of parachute failure, ThrustSSC takes longer to slow from a given speed than to accelerate to it, and the distance to stop in such an instance dictates the maximum.
By Wednesday evening everything looked good for a Thursday run. Then came a bombshell: officers from the air base rushed out to warn us that severe rain was expected. The fear was of flash flooding as the water ran off the distant hills or high winds damaging equipment - especially the crucial Aireshelta that houses the car! For a while it was ‘all hands on deck’ as additional securing lines were passed over the inflatable hangar, ‘Scania 2’ was coupled back up to the Pit Station Trailer to take some load off the legs, additional spikes hammered in to hold the satellite dish, and all loose items secured. With the overnight watch strengthened in case of problems, the remainder of the team hurried back to base before the mud flats became impassable.
In the event there was little to fear. By 2330hrs the heavy rain had come and gone again, and although the desert was sodden and extremely slippery when it came to refueling the Honda diesel-generators before bedding down in the Scanias for the night, no floods had come.
By this morning there was still standing water on the ground, and an early inspection by Richard Noble looked devastating for this year’s desert runs. But once again Jafr showed remarkable powers of self-healing, and the surprise on Richard’s face when he was told shortly after lunch that another run was planned for that afternoon was worth seeing! The desert is simply so dry after some four years without serious rain that the lower layers soak up any moisture. One lovely result of all the rain is that the area around Jafr is suddenly much greener as the hardy plants take maximum advantage.
The ambulance was quickly arranged, and the Badir desert police contacted to arrange closure of the desert during the run. At 1530hrs, ThrustSSC was towed once more out of the Aireshelta and towards the South end of Track 16. At 1615 everything was in position, although the sun was now setting fast and time was short. Just as the clock was ticking towards the start, a camel was spotted near the track. Ron Ayers was sent to ask its handler to take it clear - but was met with a refusal unless Ron gave him cigarettes. Ron doesn’t smoke, so the camel was led further across the lanes towards Track 16 and ‘hobbled’ - one leg was tie up so it couldn’t walk. The Badir were summoned and they dealt with it in short order, but it could all too easily have taken too long.
At 1625 however, the ‘Aarooogaah’ sounded three times and Jayne Millington reported calmly over Channels 1 and 2: "SSC is rolling". In the distance a plume of dust rose above the mirage as the Andy Green brought the Speys first up to maximum military power, then to minimum reheat. Both ‘burners lit as one, but as the speed rose Andy found the car drifting left despite him steering right. At 250mph and 1½ miles into the run he aborted - engines to idle, triple-parachute deployed, Recovery Team requested by radio. The speed peaked at 304mph before ThrustSSC slowed to a stop and 'Recovery' rushed to it with their Palouste air-starter as a precaution against a jet-pipe fire on engine shutdown (an known, but rare, problem with jet engines).
The usual media interviews and photos were quickly dealt with and ThrustSSC returned to the Aireshelta for diagnosis of the problem. The rear-wheel on-car camera showed excessive play in the wheel’s motion compared to Andy Green’s steering wheel - now the cause had to be found. The head of the leading rear wheel’s suspension strut was disassembled revealing that the pins through the quadrant had deformed under the enormous shear loads on the steering. Corrective action has been identified and will be undertaken before the next run of ThrustSSC.
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