Rolls-Royce is building the world’s largest airliner engine, the Trent Ultrafan

Buried deep inside the Rolls-Royce plant at Filton in Bristol is a bare brick room where the Olympus engines that powered Concorde and the Pegasus fans for the Harrier jump jet were put through their paces. Now it is testing a generator the size of a washing machine drum designed to burn green fuels and