Opel-RAK were a series of rocket vehicles produced by Fritz von Opel, of the Opel car company, in association with others, including Max Valier and Friedrich Wilhelm Sander largely as publicity stunts.
The Lippisch Ente a rocket-powered glider was produced on June 11, 1928, piloted by Fritz Stamer, but is not usually considered part of the series.
The 1937 German film Weltraum Schiff I Startet Eine Technische Fantasie has short clips of various RAK vehicles: 11 seconds at 436 feet (approximately 04:47) igniters being wired to the Rak.2 car; 2 seconds at 447 feet (approximately 04:58) Max Valier seated in a RAK.2 car labeled "RÜCKSTOSS VERSUCHS WAGEN"; 2 seconds at 451 feet (approximately 05:00) Fritz von Opel seated in a RAK.2 car; 11 seconds at 460 feet (approximately 05:06) Fritz Von Opel drives the RAK.2 car on 1928 May 23 at the Avus Track in Berlin; 2 seconds at 472 feet (05:14) Sander-Opel RAK.3 rocket car on 1928 June 23 running on railway tracks; 19 seconds at 475 feet (05:16 to 05:35) Opel-Sander RAK.1 rocket glider in 1928 September, preparation and launch; 6 seconds at 536 feet (05:57 to 06:03) Max Valier sitting and talking in a RAK.6 car.