The RS-25 engine consists of pumps, valves, and other components working in concert to produce thrust. Subsequent flights will make use of the simplified RS-25E engine, also known as the Production Restart, currently under testing and development. The first four Space Launch System flights use modernized and refurbished engines built for the Space Shuttle program. Following each flight, the RS-25 engines were removed from the orbiter, inspected, refurbished, and then reused on another mission.įour RS-25 engines are installed on each Space Launch System, housed in the engine section at the base of the core stage, and are expended after use. The engines were used for propulsion throughout the spacecraft ascent, with total thrust increased by two solid rocket boosters and the orbiter's two AJ10 orbital maneuvering system engines.
![weight of endeavour space shuttle weight of endeavour space shuttle](https://appel.nasa.gov/wp-content/uploads/2020/05/shuttle_Endeavor_sts_49-670x380.jpg)
The Space Shuttle used a cluster of three RS-25 engines mounted at the stern of the orbiter, with fuel drawn from the external tank. Components of the RS-25 operate at temperatures ranging from −253 to 3,300 ☌ (−400 to 6,000 ☏). The engine produces a specific impulse ( I sp) of 452 seconds (4.43 kN-sec/kg) in a vacuum, or 366 seconds (3.59 kN-sec/kg) at sea level, has a mass of approximately 3.5 tonnes (7,700 pounds), and is capable of throttling between 67% and 109% of its rated power level in one-percent increments. The RS-25 has undergone upgrades over its operational history to improve the engine's reliability, safety, and maintenance load.
![weight of endeavour space shuttle weight of endeavour space shuttle](https://tidbits.com/uploads/2013/11/Space-Shuttle-Endeavor.jpg)
Although RS-25 heritage traces back to the 1960s, its concerted development began in the 1970s with the first flight, STS-1, on April 12, 1981. The Aerojet Rocketdyne RS-25, also known as the Space Shuttle Main Engine ( SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is currently used on the Space Launch System (SLS).ĭesigned and manufactured in the United States by Rocketdyne (later Pratt & Whitney Rocketdyne and Aerojet Rocketdyne), the RS-25 burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing 1,859 kN (418,000 lb f) thrust at liftoff. Rocketdyne, Pratt & Whitney Rocketdyne, Aerojet Rocketdyneĭata is for RS-25D at 109% of rated power level. The bright area at the bottom of the picture is a Shock diamond