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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.

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Application
First stage engine
Associated LV
Delta IV · Delta IV Heavy
Chamber pressure
1,488 psi (10.26 MPa)
Country of origin
United States
Cycle
Gas-generator
Designer
Rocketdyne

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Overview

Design and development

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Map overview Semantic statistics

RS-68

Nodes32
Edges31
Triples83
Avg. degree1.94
Density0.0625
Components1

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RS-68

Top relations

related to Design and development · 27
RS-68 → AFRL, Air Force Research Laboratory, Apollo, California, Canoga Park, December, Delta IV, Delta IV Evolved Expendable, Edwards Air Force Base, EELV, Engine, It, Launch Vehicle, Los Angeles, Moon, NASA's Stennis Space Center, One, Power, Rocketdyne Propulsion, RS-25 Space Shuttle Main
related to Proposed uses · 13
RS-68 → Ares, Constellation, Delta IV, In, Later, NASA, NASA's, RS-25, RS-68B, Space Launch System, SSMEs, The, Thrust
related to External links · 12
RS-68 → Aerojet Rocketdyne's RS-68, AIAA, Archived, Astronautix, Century, Indiana, Indianapolis, January, Joint Liquid Propulsion Conference, March, Propulsion, Wayback MachineRS-68
related to Variants · 9
RS-68 → April, Ares, Certification, It, Its, NASA's Constellation, RS-68A, RS-68B, The Ares
Manufacturer · 3
RS-68 → Aerojet Rocketdyne (2013–2024), Pratt & Whitney Rocketdyne (2005–2013), Rocketdyne (2002–2005)
related to Human-rating · 2
RS-68 → In, NASA
Application · 1
RS-68 → First stage engine
Associated LV · 1
RS-68 → Delta IV · Delta IV Heavy
Chamber pressure · 1
RS-68 → 1,488 psi (10.26 MPa)
Country of origin · 1
RS-68 → United States

Important terminology Word statistics

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Important terminology

engine delta iv rocket launch space rocketdyne thrust engines used ares kn specific impulse rs-68a program nasa's 000 vacuum sea

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
RS-68ApplicationFirst stage engine1.00infobox
RS-68Associated LVDelta IV · Delta IV Heavy1.00infobox
RS-68Chamber pressure1,488 psi (10.26 MPa)1.00infobox
RS-68Country of originUnited States1.00infobox
RS-68CycleGas-generator1.00infobox
RS-68DesignerRocketdyne1.00infobox
RS-68Diameter2.43 m (8 ft 0 in)1.00infobox
RS-68Dry massRS-68: 6,600 kg (14,560 lb) RS-68A: 6,740 kg (14,870 lb)1.00infobox
RS-68First flight20 November 2002 (2002-11-20)1.00infobox
RS-68Last flight9 April 2024 (2024-04-09)1.00infobox
RS-68Length5.20 m (17.1 ft)1.00infobox
RS-68ManufacturerRocketdyne (2002–2005)1.00infobox
RS-68ManufacturerPratt & Whitney Rocketdyne (2005–2013)1.00infobox
RS-68ManufacturerAerojet Rocketdyne (2013–2024)1.00infobox
RS-68Nozzle ratio21.5:11.00infobox
RS-68PropellantLOX / .mw-parser-output .template-chem2-su{display:inline-block;font-size:80%;line-height:1;vertical-align:-0.35em}.mw-parser-output .template-chem2-su>span{display:block;text-a…1.00infobox
RS-68Specific impulse, vacuumRS-68: 410 s (4.0 km/s) RS-68A: 411.9 s (4.039 km/s)1.00infobox
RS-68StatusRetired1.00infobox
RS-68Thrust, sea-levelRS-68: 2,950 kN (660,000 lbf) RS-68A: 3,137 kN (705,000 lbf)1.00infobox
RS-68Thrust-to-weight ratioRS-68: 45.3:1 RS-68A: 47.4:11.00infobox

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