RS-88

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title: "RS-88" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["rocket-engines-using-alcohol-propellant", "rocketdyne-engines", "rocket-engines-of-the-united-states", "rocket-engines-using-the-pressure-fed-cycle", "rocket-engines-using-hypergolic-propellant"] description: "US ethanol-oxygen rocket engine" topic_path: "geography/united-states" source: "https://en.wikipedia.org/wiki/RS-88" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary US ethanol-oxygen rocket engine ::

::data[format=table title="Infobox rocket engine"]

Field	Value
image	RS-88 test firing.jpg
caption	An RS-88 is fired at Stennis Space Center
name	RS-88
country_of_origin
manufacturer	{{ubli
designer	Rocketdyne
type	liquid
status	Active
fuel	LOX / Ethanol
MMH / NTO (LAE variant)
cycle	Gas-generator
used_in	CST-100 Starliner
thrust(SL)	220 kN (ethanol)
176.6 kN (hypergolic)
::

| image = RS-88 test firing.jpg | caption = An RS-88 is fired at Stennis Space Center | name = RS-88 | purpose = | last_flight = | successor = | country_of_origin = | manufacturer = {{ubli | Rocketdyne (1997–2005) | Pratt & Whitney Rocketdyne (2005–2013) | Aerojet Rocketdyne (2013–present) | designer = Rocketdyne | type = liquid | status = Active | fuel = LOX / Ethanol MMH / NTO (LAE variant) | oxidiser = | cycle = Gas-generator | description = | burn_time = | used_in = CST-100 Starliner | thrust(SL) = 220 kN (ethanol) 176.6 kN (hypergolic) | thrust = 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. 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.

NASA tested the RS-88 in a series of 14 hot-fire tests, resulting in 55 seconds of successful engine operation in November and December 2003.

In 2003, Lockheed Martin selected the RS-88 for their pad abort demonstration vehicle. NASA successfully tested the engine in a series of hot-fire tests, demonstrating its reliability.

Starliner Launch Escape System

::figure[src="https://upload.wikimedia.org/wikipedia/commons/7/7b/CST-100_Starliner_-_Pad_Abort_Test,49013402052_f3852e9b3d_o.jpg" caption="Starliner"] ::

A hypergolic derivative of the RS-88, fueled by monomethylhydrazine (MMH) and nitrogen tetroxide, was chosen as the launch escape motor for the Boeing Starliner capsule. This variant, called the Launch Abort Engine (LAE), provides 176.6 kN of thrust. Four LAE engines are used in Starliner's abort system to propel the capsule away from the launch vehicle in case of an emergency.

References

References

1. (June 9, 1997). "NASA Selects Four Companies to Demonstrate Low Cost Launch System Technologies". NASA.
2. (June 1997). "Low Cost Technologies". NASA.
3. (15 March 2011). "Test of Rocketdyne abort motor for Boeing crew capsule". YouTube.
4. Clark, Stephen. (November 27, 2015). "Aerojet Rocketdyne wins propulsion contracts worth nearly $1.4 billion".
5. (Mar 22, 2012). "PWR Analyzing Hot-Fire Tests For CST-100 Launch Abort Engine.". Beyond Earth.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::