The Walter HWK 109-509 powered the first piloted aircraft of any type to exceed how many MPH in level flight?
Walter HWK 509 The Walter HWK 109-509 was a German liquid-fuel bipropellant rocket engine that powered the Messerschmitt Me 163 Komet and Bachem Ba 349 aircraft. It was produced by Hellmuth Walter Kommanditgesellschaft (HWK) commencing in 1943.
George Stainforth Wing Commander George Hedley Stainforth AFC RAF (1899 - 27 September 1942) was a British Royal Air Force pilot and the first man to exceed 400 miles per hour.