Fritz Adam Hermann von Opel (May 4 1889 - April 8 1971) was the only child of Wilhelm von Opel, and a grandson of Adam Opel, founder of the Opel Company. He is remembered mostly for his spectacular demonstrations of rocket propulsion that earned him the nickname "Rocket Fritz".
Von Opel was born in Rüsselheim and educated at the technical university of Darmstadt. After graduation, he was made director of testing for Opel and also put in charge of publicity. In the 1920s, he became interested in using rockets in publicity stunts for the company and sought advice from Max Valier of the newly-formed Verein für Raumschiffahrt (VfR - "Spaceflight Society") and Friedrich Sander, a pyrotechnics manufacturer from Bremerhaven.
On March 15 1928, von Opel tested his first rocket-powered car, the RAK.1 and achieved a top speed of 75 km/h (47 mph) in it, proving the concept. Less than two months later, he reached a speed of 230 km/h (143 mph) in the RAK.2, driven by 24 solid-rockets.
Later that same year, he purchased a sailplane named the Ente from Alexander Lippisch and attached rocket motors to it, creating the world's first rocket plane on June 11. The aircraft exploded on its second test-flight, before von Opel had a chance to pilot it himself, so he commissioned a new aircraft, also called the RAK.1 from Julius Hatry, and flew it at Frankfurt-am-Main on September 30 1929. In the meantime, another mishap had claimed the RAK.3, a rocket powered railway car powered by 30 solid rockets and which reached a speed of 254 km/h (157 mph).
Von Opel left the Opel company and Germany after 1929 and died in Samedan, Switzerland.