The RS-83 was a

rocket engine A rocket engine is a reaction engine, producing thrust in accordance with Newton's third law by ejecting reaction mass rearward, usually a high-speed Jet (fluid), jet of high-temperature gas produced by the combustion of rocket propellants stor ...

design for a reusable

liquid hydrogen Liquid hydrogen () is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecule, molecular H2 form. To exist as a liquid, H2 must be cooled below its critical point (thermodynamics), critical point of 33 Kelvins, ...

liquid oxygen Liquid oxygen, sometimes abbreviated as LOX or LOXygen, is a clear cyan liquid form of dioxygen . It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an application which is ongoing. Physical ...

rocket larger and more powerful than any other. The RS-83 was designed to last 100 missions, and was intended for use on the first

stage Stage, stages, or staging may refer to: Arts and media Acting * Stage (theatre), a space for the performance of theatrical productions * Theatre, a branch of the performing arts, often referred to as "the stage" * ''The Stage'', a weekly Brit ...

of a two-stage-to-orbit

reusable launch vehicle A reusable launch vehicle has parts that can be recovered and reflown, while carrying payloads from the surface to outer space. Rocket stages are the most common launch vehicle parts aimed for reuse. Smaller parts such as fairings, booster ...

Development

It was developed by

Rocketdyne Rocketdyne is an American rocket engine design and production company headquartered in Canoga Park, California, Canoga Park, in the western San Fernando Valley of suburban Los Angeles, California, Los Angeles, in southern California. Rocketdyne ...

Propulsion and Power, located in

Canoga Park, California Canoga Park is a neighborhood in the San Fernando Valley region of the City of Los Angeles, California. Before the Mexican–American War, the district was part of a Ranchos of California, rancho, and after the American victory it was converted ...

to power the launch vehicle as part of the

Space Launch Initiative The Space Launch Initiative (SLI) was a NASA and U.S. Department of Defense joint research and technology project to determine the requirements to meet all the nation's hypersonics, space launch and space technology needs. It was also known as the ...

(SLI) program. This engine was designed to produce a thrust of at sea level and in a vacuum with an ''I''_sp of and respectively. The engine was designed to use many new technologies including ones developed for the

Space Shuttle Main Engine The 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 used on the Space Launch System. Designed and manufactured in the United States by Rocketd ...

(SSME). Technologies include channel wall regenerative nozzles, hydrostatic bearings, and turbine damping. The RS-83 is loosely based on the

RS-68 The RS-68 (Rocket System-68) was a liquid-fuel rocket engine that used liquid hydrogen (LH2) and liquid oxygen (LOX) as propellants in a gas-generator cycle. It was the largest hydrogen-fueled rocket engine ever flown. Designed and manufacture ...

that powers the

Delta IV Delta IV was a group of five expendable launch systems in the Delta rocket family. It flew 45 missions from 2002 to 2024. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) p ...

expendable launch vehicle. The RS-83 design is more efficient, lighter, slightly stronger, and yet reusable. The engine design weight was with an engine

thrust to weight ratio Thrust-to-weight ratio is a dimensionless quantity, dimensionless ratio of thrust to weight of a rocket, jet engine, Propeller (aircraft), propeller engine, or a vehicle propelled by such an engine that is an indicator of the performance of the eng ...

of 52 at launch. One of the main goals of SLI was to develop components of a reusable launch vehicle with high reliability. The RS-83 was designed for a loss of vehicle rate of 1 in 1,000. Another goal of the program was to dramatically reduce the cost per unit weight of payload to

low Earth orbit A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial object ...

. The RS-83 was designed with the goal of $1,000/lb ($2,200/kg). The engine passed numerous design reviews and was on schedule for prototype testing in 2005 before the SLI program was cancelled. NASA changed its focus to

expendable launch system An expendable launch system (or expendable launch vehicle/ELV) is a launch vehicle that can be launched only once, after which its components are destroyed during reentry or impact with Earth, or discarded in space. ELVs typically consist of s ...

s used in the

Constellation program The Constellation program (abbreviated CxP) was a crewed spaceflight program developed by NASA, the space agency of the United States, from 2005 to 2009. The major goals of the program were "completion of the International Space Station" and a " ...

for

human spaceflight Human spaceflight (also referred to as manned spaceflight or crewed spaceflight) is spaceflight with a crew or passengers aboard a spacecraft, often with the spacecraft being operated directly by the onboard human crew. Spacecraft can also be ...

s to the Moon and Mars.

References

{{reflist

External links

Stennis Space Center page.
Rocket engines using the gas-generator cycle Rocketdyne engines Rocket engines using hydrogen propellant Rocket engines of the United States

Development

See also

References

External links