WASSERFALL
Beginning in early 1943 (one source gives September, 1942 as the starting date), the entire resources of the Peenemunde group were concentrated on the development of an antiaircraft guided rocket first designated C-2 and later Wasserfall. The first experimental firing was made on 28 February 1944. By January, 1945, 25 experimental firings had been made, all but one with radio control. Fifteen of the firings gave satisfactory flight.
The Wasserfall missile is 88 cm in diameter, 783 cm long, has a launching weight of 3570 kg, and a final weight of 1615 kg with pay load of 305 kg of explosive. It is rocket propelled for 45 sec with a liquid-fuel rocket of 8000-kg thrust. The maximum speed is about 770 m/sec and its maximum height 18.3 km. The horizontal range is 26.5 km.
The control method was designated "Rheinland" which was to be developed in four stages. In the first stage, the rocket was to be steered by direct radio control according to the eclipse procedure as used for FX1400 and Hs-293 with the aid of optical two-axis tracking apparatus. The Kehl-Strasburg meter-wave control transmitter was to be used. At night searchlight beams were to be used. So far as known at present the tests completed were made with this equipment.
The second stage used radar tracking of missile and target with a suitable visual presentation. A human operator was still used with radio transmission of the control information.
The third stage was the automatic control, the radar-tracking device being coupled through a suitable computer to the control stick.
The fourth stage was beam guiding with a homing device for the final stage of the trajectory.
According to one report (unpublished and unfinished manuscript on "Systems of Beam Guiding" found at LFA Braunschweig), dated 28 March 1945, it had been determined by the Peenemunde group that the control described as the second stage above could not be carried out because of the slowness of the human brain and that therefore the control signals must be formed electrically and transmitted automatically to the missile.
The Peenemunde group developed an infrared proximity fuse for use with Wasserfall.
The history of the aerodynamic development of Wasserfall is given in a report WV A 171 by Dr. Kurzweg entitled "The Aerodynamic Development of the Flak Rocket Wasserfall." This interesting document brings out the fact that Wasserfall was, in addition to its immediate application, a contribution to the aerodynamic development of the long-range winged rocket. More than 25 designs were tested in the supersonic wind tunnel at speeds up to three times the speed of sound. The lift-drag ratio was 4.15 at low speeds, 4.42 at Mach number 0.6, 3.90 at Mach number 0.84, 2.90 at Mach number 2.90.
No data are available to the writer on the production plans for Wasserfall. On 6 February 1945 the SS leader Kammler who had been given authority over the development of guided missiles stated that the Wasserfall project would be closed out at the end of the development period, priority being given to unguided rockets such as Taifun.