Andy Green remains the only individual to have broken the sound barrier on land. On Tuesday, he achieved new milestones, setting several speed records in a hydrogen-powered or clean-energy car, surpassing all previous official achievements.
Operating a specially engineered race car named the Hydromax, designed by the construction equipment company JCB, the 64-year-old retired British fighter pilot made two record-setting attempts. In his initial run, he reached an average speed of 400.623 miles per hour, while in the second, he achieved 412.135 mph. The combined average speed for these attempts was 406.320 mph.
Green is renowned for holding the current overall land speed record, having reached 763.035 miles per hour in a jet engine-powered race car in 1997. This record, which has stood for nearly three decades, marks the only occasion where a person has surpassed the speed of sound on land.
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The race on Tuesday broke three existing records recognized by the International Automobile Federation (FIA), the global authority for motorsports: the fastest hydrogen internal combustion engine at 185.5 mph, the fastest hydrogen fuel cell car at 303 mph, and the fastest electric vehicle at 342 mph.
The JCB Hydromax is classified as a blown gas streamliner, a type of race car built to achieve extraordinary speeds on straight paths. “Blown gas” refers to the car’s use of a supercharger, which injects more air into the engine, enhancing fuel combustion.
Unlike typical road vehicles, the Hydromax is a 32-foot-long machine fitted with two 800-horsepower engines, one positioned in front of the driver and the other behind.
Instead of gasoline or diesel, the Hydromax employs air to ignite hydrogen, powering the engines while significantly reducing emissions compared to conventional internal combustion engines.
“This record was set by production-based engines, the same engines powering JCB diggers right now,” stated JCB chairman Anthony Bamford in a statement. “That is the point of JCB Hydromax: it shows hydrogen works, and it works today at the highest level with zero emissions.”
Green established this record at the renowned Bonneville Salt Flats in Utah, a site famous for setting numerous land speed records. On August 5, Green again piloted the car, achieving an average speed of 368.347 miles per hour over two runs, marking a high achievement in the Southern California Timing Association’s blown gas streamliner category. In one of these runs, the Hydromax reached a peak speed of 369.554 miles per hour.
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