Projekt RAK

"Projekt RAK" sheds light on the adventure of the rocket tests of Opel, the largest German car manufacturer in the 1920s, from the first empirically conducted tests, through the development of the first solid booster, to the completely unknown secret development of technology with liquid fuel components. The first test runs with solid-fuel rockets in January 1928 already showed that the known efficiency of approx. 3 to 5% can be increased to almost 20% with simple, intelligent measures. This enormous increase in performance was achieved through a sophisticated nozzle shape and through the use of modern hydraulic presses to increase the energy density of the powder mixture. The Opel body presses were the inspiration for the first hydraulic press to solidify the powder mixture in the rocket casings. They were designed by Fritz von Opel for this purpose, built in the mechanical engineering department of the Opel works and installed in the Sander powder rocket factory in Wesermünde. The explosions of the Opel RAK 3 and RAK 4, caused by the formation of hairline cracks in the glass-hard compressed powder mixture, did not lead to a setback in the development of solid-fuel rockets, but to new innovative impulses. "Project RAK" describes for the first time in detail the world's first manned rocket test on March 12, 1928 in Rüsselsheim, which was carried out with a previously unknown preliminary test vehicle. Includes previously unpublished image material.