RL10A-4-1B
Pratt & Whitney RL10A-4-1B cryogenic upper-stage engine used by the Atlas IIIA and Atlas IIIB Centaur configurations.
Identity
- Aliases
- RL10A-4-1BRL10A-4-1B engine
- Domains
- spaceflight
- Identity Level
- variant
- Kind
- liquid-rocket-engine
- Name
- RL10A-4-1B
- Status
- retired
Details
- Description
- Pratt & Whitney RL10A-4-1B cryogenic upper-stage engine used by the Atlas IIIA and Atlas IIIB Centaur configurations.
- Developers
- Family
- Propellants
- liquid hydrogenliquid oxygen
Links
Assets & Meta
- Creation Time
- August 1, 2026 at 13:48:22 UTC
- Updated Time
- August 1, 2026 at 13:48:22 UTC
Other
- Sources
- Accessed Date
- 2026-08-01
- Note
- ULA identifies the Atlas IIIA and IIIB vehicles as using the RL10A-4-1B engine and distinguishes the single- and dual-engine Centaur configurations.
- Publisher
- United Launch Alliance
- Title
- The Centaur Upper Stage Vehicle
- Accessed Date
- 2026-08-01
- Note
- ULA records one RL10A-4-1B on Atlas IIIA and the stretched Atlas IIIB Centaur as configurable with one or two RL10A-4-1B engines.
- Publisher
- United Launch Alliance
- Title
- Human Rating Atlas Heritage and Future Potential
- Accessed Date
- 2026-08-01
- Note
- NASA documents the RL10 derivative lineage, including the RL10A-4-1 family used for Atlas/Centaur upper-stage development.
- Publisher
- NASA Technical Reports Server
- Title
- Cryogenic upper stage propulsion: RL10 and derivative engines