RD-181
NPO Energomash RD-181 is a single-chamber liquid-oxygen/kerosene first-stage engine derived from RD-191 for Antares. NASA describes its oxygen-rich staged-combustion cycle, throttling, and variable mixture-ratio control; the Northrop Grumman Antares guide reports approximately 2,085 kN vacuum thrust per engine at full throttle. Antares 230 used two RD-181 engines and a first-stage burn of about 209 s.
Identity
- Aliases
- RD-181РД-181NPO Energomash RD-181Antares RD-181
- Domains
- spaceflight
- Identity Level
- model
- Kind
- liquid-rocket-engine
- Name
- RD-181
- Status
- retired
Details
- Description
- NPO Energomash RD-181 is a single-chamber liquid-oxygen/kerosene first-stage engine derived from RD-191 for Antares. NASA describes its oxygen-rich staged-combustion cycle, throttling, and variable mixture-ratio control; the Northrop Grumman Antares guide reports approximately 2,085 kN vacuum thrust per engine at full throttle. Antares 230 used two RD-181 engines and a first-stage burn of about 209 s.
- Developers
- Family
- Lineage
- Note
- RSC Energia states that RD-181 was derived from RD-191 specifically for Antares.
- Related Propulsion System
- Relationship
- direct-derivative-of
- Sources
- Accessed Date
- 2026-07-29
- Publisher
- RSC Energia press release archived by MarketScreener
- Title
- RSC Energia and Orbital Sciences Corporation sign direct contract for the delivery of engines
- Manufacturers
- Propellants
- liquid oxygenkerosene
- Retirement Date
- 2023-08
- Rocket Specs
- Chamber Count
- 1
- Cycle
- oxidizer-rich staged combustion
- Vacuum Thrust Kn
- 2,085
Links
Assets & Meta
- Creation Time
- July 29, 2026 at 09:56:25 UTC
- Updated Time
- August 22, 2026 at 07:39:37 UTC
Other
- Sources
- Accessed Date
- 2026-07-29
- Publisher
- NASA
- Title
- Meet the New Engines of the Antares Rocket
- Accessed Date
- 2026-07-29
- Publisher
- RSC Energia press release archived by MarketScreener
- Title
- RSC Energia and Orbital Sciences Corporation sign direct contract for the delivery of engines
- Accessed Date
- 2026-07-29
- Note
- Supports the legacy vehicle installation and the narrow canonical identity used for migration.
- Publisher
- Official vehicle or program source
- Title
- Antares 230 official vehicle reference
- Accessed Date
- 2026-08-22
- Note
- Northrop Grumman guide reports approximately 2,085 kN vacuum thrust per RD-181 and an oxygen-rich staged-combustion cycle.
- Publisher
- Northrop Grumman
- Title
- Antares User Guide