The Me262A-1a was the world's first jet propelled fighter aircraft used in actual combats. Its development started in spring of 1939, and its first jet propelled flight with Jumo 004A-0 jet engines was made on July 18, 1942. However, full production was delayed until the summer of 1944 due to a modification to the bomber version. The Me262A-1A was highly successful in aerial combat.