Italy and the Soviet Union had both tested motorjet aircraft which had turbines powered by piston engines and the latter had also equipped several types of conventional piston-powered fighter aircraft with auxiliary ramjet engines for testing purposes.
By the end of the conflict on 2 September 1945 Germany, the United Kingdom, and the United States all had operational turbojet-powered fighter aircraft while Japan had produced, but not used, motorjet-powered kamikaze aircraft, and had tested and ordered into production conventional jets. The first successful jet aircraft, the Heinkel He 178, flew only five days before the 1 September 1939 start of the war. World War II was the first war in which jet aircraft participated in combat with examples being used on both sides of the conflict during the latter stages of the war. A captured Messerschmitt Me 262, the most numerous jet fighter of World War II
