During the 1920s, a number of rocket research organizations appeared worldwide. In 1927 the German car manufacturer Opel began to research rocket vehicles together with Mark Valier and the solid-fuel rocket builder Friedrich Wilhelm Sander. In 1928, Fritz von Opel drove with a rocket car, the Opel-RAK.1 on the Opel raceway in Rüsselsheim, Germany. In 1928 the Lippisch Ente flew, rocket power was used to launch the manned glider, although it was destroyed on its second flight. In 1929 von Opel started at the Frankfurt-Rebstock airport with the Opel-Sander RAK 1-airplane, which was damaged beyond repair during a hard landing after its first flight.
In the mid-1920s, German scientists had begun experimenting with rockets which used liquid propellants capable of reaching relatively high altitudes and distances. In 1927 and also in Germany, a team of amateur rocket engineers had formed the Verein für Raumschiffahrt (German Rocket Society, or VfR), and in 1931 launched a liquid propellant rocket (using oxygen and gasoline).