1928 Opel RAK-1 rocket car with Sanders rocket propulsion in tail

A series of rocket powered cars, railway vehicles, and planes were commissioned and, in some cases, driven or piloted, by Fritz von Opel, of the Opel car company. Opel helped pioneer rocket vehicle development in association with others, including Max Valier and Wilhelm Sander.

The Opel-RAK-1, the world's first rocket-propelled car was driven by Kurt C. Volkhart to a top speed of 75 km/h (47 mph) on March 15, 1928. On May 23, 1928 he reached a speed of 230 km/h (143 mph) in an improved version, the RAK-2, driven by 24 solid-fuel rockets.

Later that same year, Opel purchased a sailplane named the Ente (German for "duck") from Alexander Lippisch and attached rocket motors to it, creating the world's first rocket plane on June 11, 1928. The aircraft exploded on its second test-flight, before Opel had a chance to pilot it himself, so he commissioned a new aircraft from Julius Hatry, and flew it at Frankfurt-am-Main on September 30, 1929. This plane is also known as the Opel RAK-1, or, alternatively, as the Opel-Hatry RAK-1 or Opel-Sander RAK-1 in acknowledgement of its builder or the supplier of its engines respectively. In still other references it is called the RAK-3 to distinguish it from Opel's previous RAK-1 and RAK-2 rocket cars. As it happened, all three names, Opel, Sander, and Hatry were painted on the aircraft (with Opel’s most prominent), as was the RAK-1 designatio