The Messerschmitt Me 163 Komet, designed by Alexander Lippisch, was a German rocket-powered fighter aircraft. It is the only rocket-powered fighter aircraft ever to have been operational and the first piloted aircraft of any type to exceed 1000 km/h (621 mph) in level flight.
Its design was revolutionary and its performance unprecedented. German test pilot Heini Dittmar in early July 1944 reached 1,130 km/h (700 mph), an unofficial flight airspeed record unmatched by turbojet-powered aircraft for almost a decade. Over 300 aircraft were built, but the Komet proved ineffective in its dedicated role as an interceptor aircraft and was responsible for the destruction of only about nine to eighteen Allied aircraft against ten losses. Aside from combat losses many pilots were killed during testing and training.
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