I photographed these Titan I Rocket Engine examples(first stage and second stage) at the Udvar-Hazy and South Dakota Air Museum
The Aerojet General LR91-AJ-3 engine was used to propel the second stage of the Titan I ICBM to a speed of Mach 15. The Titan engine was instrumental in the flight of the Gemini space missions, including the first space walk and first docking of space craft.