The Ruhrstahl X-4 was a wire guided air-to-air missile designed by Germany during World War II. The X-4 did not see operational service and thus was not proven in combat. Work on the X-4 began in June 1943, by Dr Max Kramer at Ruhrstahl. The idea was to build a missile with enough range to allow it to be fired from outside the range of the bombers' guns , while being guided with enough accuracy to guarantee a "kill". The X-4 met these specifications and more; its BMW 109-448 rocket motor accelerated the missile to over 1150 km/h and kept it there during its "cruise", between 1.5 and 4 km, while the defensive guns had a maximum effective range of about 1000 m. The missile was stabilized by spinning it slowly in flight, at about 60 rpm. This meant any asymmetrical thrust from the engine, or inaccuracies in the control surfaces, would be evened out as the missile spun. Signals were sent to the missile over two wires wound onto spools on the missile body, and corrected the direction of flight by operating control surfaces on the tail. The warhead consisted of a 20 kg fragmentation device that had a lethal radius of about 8 m. The first flight test occurred on August 11, 1944 using a Focke-Wulf Fw 190 to as the launch platform. Subsequent tests used the Junkers Ju 88 and Messerschmitt Me 262, although they were not launched from the latter. The X-4 had originally been intended for use by single-seat fighters, but the problems in guiding both the missile and the aircraft at the <b>...</b>

The Ruhrstahl X-4 was a wire guided air-to-air missile designed by Germany during World War II. The X-4 did not see operational service and thus was not proven in combat. Work on the X-4 began in June 1943, by Dr Max Kramer at Ruhrstahl. The idea was to build a missile with enough range to allow it to be fired from outside the range of the bombers' guns , while being guided with enough accuracy to guarantee a "kill". The X-4 met these specifications and more; its BMW 109-448 rocket motor accelerated the missile to over 1150 km/h and kept it there during its "cruise", between 1.5 and 4 km, while the defensive guns had a maximum effective range of about 1000 m. The missile was stabilized by spinning it slowly in flight, at about 60 rpm. This meant any asymmetrical thrust from the engine, or inaccuracies in the control surfaces, would be evened out as the missile spun. Signals were sent to the missile over two wires wound onto spools on the missile body, and corrected the direction of flight by operating control surfaces on the tail. The warhead consisted of a 20 kg fragmentation device that had a lethal radius of about 8 m. The first flight test occurred on August 11, 1944 using a Focke-Wulf Fw 190 to as the launch platform. Subsequent tests used the Junkers Ju 88 and Messerschmitt Me 262, although they were not launched from the latter. The X-4 had originally been intended for use by single-seat fighters, but the problems in guiding both the missile and the aircraft at the <b>...</b>