By the beginning of 1943 the command of Nazi Germany realized that the threat from enemy bombers Requests find new means to combat it. Fighter aircraft with barreled weapons and anti-aircraft artillery could resist perfectly bomber raids, but the effectiveness of such struggles in the future in doubt. In this regard, the imperial ministry of aviation immediately initiated several promising projects to develop missile technology, created to destroy enemy aircraft. German engineers began development of several anti-aircraft missiles and guided munitions «air-to-air.» One of the new developments was the air-launched rocket Ruhrstahl X-4.
Development of a guided missile X-4 began in the first months of 1943 the company Ruhrstahl Allgemeine Gesellschaft. Project manager appointed Dr. Max Kramer, formerly intensively engaged in control systems for aircraft guns promising. Number of developments under the previous project was used in the development of X-4 missiles.
Analysis of several preparatory projects will determine the aerodynamic look more successful rocket assembly and its internal volume. It should be noted, used layout solutions with some modifications in the upcoming used extensively by designers of various countries. All major items of equipment located inside the cigar-shaped body. In the fore part of the Corresponding elongated cone, in the middle — four wings and tail — X-shaped stabilizer. Housing design, wings and rudders promising missiles X-4 was created taking into account that the product will collect workers with low skills. Perhaps this is the feature of the project has allowed in 1944-1945 to collect quite a number of new missiles.
Launch X-4, in comparison with other German guided weapons came comparable light and compact. With an overall length a little more than 2-meters fueled rocket weighed 60 kg. The diameter of the largest part of the body was equal 0.22 m and a wingspan of 0.72 m superior missile body is invited to do a 3-forged duralumin parts and wings — plywood.
In the corresponding rocket nose cone positioned acoustic fuse Kranich. It was assumed that this device is tuned to the frequency of sound engines bomber B-17 would undermine the warhead at a distance of 7 meters from the plane of the target. At such a distance of 20-kilogram warhead could inflict severe damage to the target or to destroy it. In case of failure of the acoustic fuse missile X-4 received an additional pin.
The middle body portion extends for fuel tanks (capacity of 2 liter) and oxidant (4.5 liters). Near the tanks provided space for the cylinder with compressed air used pressurized feed system of fuel and oxidizer. Similar accommodation tanks allowed to reduce configuration centering as generating fuel. During the flight, the rocket’s center of mass almost moved along its longitudinal axis. By pipeline fuel and oxidizer is fed to the liquid rocket engine placed in the rear of the rocket.
As the power plant was elected engine BMW-Flugmotorenbau 109,448. This engine, using R-Stoff fuel and oxidizer S-Stoff, for 17 seconds could provide thrust up to 140 kg. Notwithstanding the applicable properties, liquid engine did not look very comfortable to use in the army. Implementation brutal fuel component (eg, S-Stoff oxidizer 95% consisted of nitric acid) could significantly hamper operation of missiles in parts of the Luftwaffe. For this reason, from the beginning of the sample taken to equip the X-4 missile solid fuel engine. There is information about the work on the modification of the rocket engine is used with parameters Schmidding 109-603 thrust liquid at 109-448, but with the smallest duration of work.
Because of the difficulty and overhead of other variants of the missile X-4 has a wired remote control system FuG 510/238. Endings on 2-wings were end fairings, which were placed inside the spool with wires. After missile launch wire unwound and provides the signal from the remote control apparatus missiles. To control the tilt and pitch used controls, located on the tail fin. Pilot aircraft carrier, using its own remote control, had to direct the missile by the method 3 points. Objective of the pilot was to introduce missiles at a small distance from the target. Once the distance is reduced to a minimum, automatic rocket without the help of others produced undermining warhead. For the convenience of the pilot on the endings 2-wings were flashing lights.
Properties of liquid motor have allowed BMW 109-448 rocket X-4 accelerate to 1100-1150 km per hour. Effective range of fire purposes does not exceed 1.5-2 km, but the calculated value of this parameter was even higher. Thus, 2-coil is placed at 5500 meters of wire weighing about 5 kg. But the main problem associated with increased range, was not the length of the wires, and the supervision of ammunition.
In the conditions of a real air combat missile Ruhrstahl X-4 was proposed to use the subsequent manner. Fighter pilot had to go to the tail of a group of enemy bombers and, approaching at a distance of less than 2-2.5 km, create rocket launch. Next using the control lever was necessary to detain a rocket to the line of motion, which was the end point of the target. Acoustic fuse tangible simplified the work of the pilot.
August 11, 1944 took place the first test launch of the newest aircraft missiles X-4. As the aircraft carrier was used modified fighter FW-190. These tests have shown the advantages and shortcomings of some applied technical solutions. First, once again proved the operational complexity of liquid rockets. In addition, X-4 missile was not very comfortable for use in single-seat fighter: the simultaneous control of the aircraft and missile guidance to the target proved quite a challenge. In this regard, there was a proposal to use as a carrier rockets modified bomber Ju-88. With all this equipment plans for the desired equipment jet fighter Me-262 is a live. Later rocket Ruhrstahl X-4 had become the main weapon fighter Focke-Wulf Ta-183 Huckebein, which, but has remained on paper.
Recent tests missiles «air-air» lasted until February 1945. In December 44th, it was decided to start serial production of new ammunition. It is worth noting that before the test was made more than 200 new missiles. According to various sources, the company Ruhrstahl Allgemeine Gesellschaft in general difficulties managed to collect a few hundred missiles X-4, but their precise number is unknown. The total quantity of product made in a variety of sources ranging from 1000 to 1300 units. Supposed to make more missiles, but anti-Hitler coalition bombers killed plant, which carried liquid rocket engines. In this regard, the creation of rockets Ruhrstahl X-4 over. Shortly before stopping production of missiles X-4, in February 1945, was discontinued assembly tools other managed class «air-to-air.» According to the results of comparisons missile Henschel Hs-298 was recognized as the least promising and discontinued. So Makar, BMW factory liquidation resulted in complete stoppage of German aircraft missiles.
Information about the combat use of guided missiles Ruhrstahl X-4 is absent. Perhaps because of problems at the front and in the rear of these munitions have not acted in part. Ready missiles were destroyed during the fighting, and the few remaining products have become trophies allies.
After the war, the French designers, using rockets and acquired documents, attempted to make his own version of the controlled aircraft missiles X-4. AA-10 project came diverse. In the years 1947-1950 the French industry has made about 200 missiles, after the project was canceled. Already at the stage of testing individual units French spetsy faced with exactly the same neuvvyazkami that the Germans a few years earlier. Used fuel and oxidizer were very brutal for implementation in aircraft armament systems. Because of problems with the safe operation of the AA-10 missile recognized inapplicable for adopting.