The RS-88 (Rocket System-88) is a liquid-fueled rocket engine designed and built in the United States by Rocketdyne (later Pratt & Whitney Rocketdyne and then Aerojet Rocketdyne). Originally developed for NASA's Bantam System Technology program in 1997, the RS-88 burned ethanol fuel with liquid oxygen (LOX) as the oxidizer. It offered 220 kN of thrust at sea level.
A hypergolic derivative of the RS-88, fueled by monomethylhydrazine and nitrogen tetroxide, was chosen as the launch escape motor for the Boeing Starliner capsule.
Origins and Testing
The RS-88 stemmed from NASA's Bantam System Technology Project, part of the Low-Cost Technologies effort of the larger Advanced Space Transportation Program.[1] This project aimed to research and demonstrate technologies for a new, affordable launch system. While the program envisioned a technology demonstration flight in late 1999, it ultimately focused on engine development.[2]