The Me-163 �Komet� wound up being the sole functional rocket-powered fighter aircraft during WWII. The Me-163 �A� project rule called �Project X� started in 1937 under Dr. Alexander Lippisch. It had been created for protection purposes utilizing rocket devices. Initial Me-163 travelled in 1941. There has been gas usage and engine efficiency problems, which limited its range. In August 1943, the Me-163 B was made with further improvements. Manufacturing started in July 1944 and a complete of 279 was at reality provided for the Luftwaffe.