On 27 August 1938, British racing driver Captain George E. T. Eyston established a new world land-speed record at Utah's Bonneville Salt Flats, driving the enormous Thunderbolt. The seven-ton, eight-wheeled machine averaged 345.49 mph (556.0 km/h) over the flying mile, eclipsing Eyston's own 1937 record of 311.42 mph.
Thunderbolt was powered by two supercharged Rolls-Royce R V12 aero engines, each capable of producing more than 2,000 horsepower. Eyston had helped design the machine, which was built by Bean Cars in Britain. Its extraordinary scale and engineering reflected the intense technological competition surrounding land-speed records during the 1930s.
The achievement, however, lasted only weeks. Rival British driver John Cobb raised the record to 350.2 mph on 15 September. Eyston responded the following day, taking Thunderbolt back to 357.5 mph, another world record.
The 1938 battles between Eyston and Cobb became a defining chapter in the golden age of land-speed racing, demonstrating how aerodynamics, power and engineering were converging at the limits of terrestrial speed.
