Award for the supersonic car

Citation

Wilson, B. (1998), "Award for the supersonic car", Industrial Lubrication and Tribology, Vol. 50 No. 1. https://doi.org/10.1108/ilt.1998.01850aaa.001

Award for the supersonic car

Award for the supersonic car

Recognition as the engineering achievement of the year, if not the decade, is the significance of the annual Award of Engineering presented to the Thrust SSC team leader Richard Noble by the Duke of Kent, president of the Engineering Council.

Without the unsung achievements of its bearings, seals, brakes and lubricants Andy Green would not have been able to go at supersonic speeds in the Thrust SSC car last 15 October.

Thrust SSC is a 16.4m long by 3.6m wide vehicle with its 10.4 tonne weight supported on four forged aluminium alloy wheels without rubber tyres. The wheels were designed to resist centrifugal forces of up to 35,000 G. Its active suspension enabled the nose of the car to be lowered as the speed approached transonic. The car's two Rolls-Royce Spey 202 gas turbine engines with afterburners developed 82,000kW and delivered 20.9 tonnes thrust. At full power the fuel consumption was 18 litres a second giving an acceleration of 1.3 G. This took the car from stationary to supersonic and back in 90 seconds, during which time it had travelled 11 miles.

Deceleration was first by parachutes and then friction brakes; Richard Noble's achievement was to build up and manage a team against formidable odds. Together they beat his previous land speed record of 633.5mph in Thrust 2 set in 1983 by reaching an astonishing 764mph at Black Rock Desert, Nevada.

Breaking the record involved more than 200 engineering partners and 100,000 man-hours of work. Standard bearing assemblies were used for the steering, gearbox and suspension units. The unique bearing assemblies fitted to the wheels were the result of two years of design, testing and development by SKF engineers at Milton Keynes. SKF reckons that 85-90 per cent of its Thrust SSC bearing work was based on proven engineering experience coming from its involvement with virtually every Formula 1 racing team. But Formula 1 cars reach speeds of 250mph only. The SKF team came up with angular contact hybrid ceramic and steel bearings each with 15 silicon nitride balls 15.875mm in diameter positioned to have a contact angle of 15 degrees on the steel raceways. Ceramic balls were chosen because their low density and low friction reduced contact stresses, heat generation and gave good case stability. Tests run at Al Jaffr in Jordan earlier in the year at speeds up to 7,000rpm confirmed the low running temperature rises predicted by the theoretical models. All the lubricants were supplied by Castrol, from the aircraft turbine oils to the highly specialised grease in the wheel bearings.

Commercial sponsors took an enormous risk in supporting the supersonic car project which had been on the verge of collapsing on many occasions. The technical achievement has still not been adequately recognised by those who call engineering and tribology boring.