On 16 January 1930, a 22-year-old Royal Air Force cadet named Frank Whittle filed British Patent No. 347,206, proposing a gas turbine that would propel an aircraft directly by its exhaust. The patent drawing showed a two-stage axial compressor feeding a single-stage centrifugal compressor, thence to radial combustion chambers and a single-stage axial turbine — the architectural DNA of every modern turbojet. Whittle's idea was rejected by the Air Ministry as impractical, and the patent itself lapsed in 1934 when he could not afford the £5 renewal fee. But in 1936, with the backing of investment bankers O.T. Falk and Partners, Power Jets Ltd was formed. The first experimental engine — designated WU — ran on 12 April 1937 at the British Thomson-Houston works in Rugby, producing thrust that was modest but unmistakably revolutionary. The flight-worthy W1 followed, and by 1941 the Whittle W1X was flown to America to seed General Electric's jet development at Lynn, Massachusetts.