The Me-163 �Komet� was truly the only operational rocket-powered fighter aircraft during WWII. The Me-163 �A� project rule named �Project X� were only available in 1937 under Dr. Alexander Lippisch. It was designed for defense purposes making use of rocket engines. The initial Me-163 flew in 1941. There were gas consumption and engine effectiveness dilemmas, which limited its range. In August 1943, the Me-163 B was developed with further improvements. Production were only available in July 1944 and an overall total of 279 had been sent to the Luftwaffe.