RD-171M
The modernized four-chamber RD-171M liquid rocket engine uses oxidizer-rich staged combustion of liquid oxygen and kerosene for the first stage of Zenit launch vehicles. Glavkosmos lists 740 tf sea-level / 806 tf vacuum thrust, 309/337 s specific impulse, 9,300 kg dry mass, and 4.15 m x 3.565 m dimensions.
Identity
- Domains
- spaceflight
- Identity Level
- model
- Kind
- liquid-rocket-engine
- Name
- RD-171M
- Status
- retired
Details
- Description
- The modernized four-chamber RD-171M liquid rocket engine uses oxidizer-rich staged combustion of liquid oxygen and kerosene for the first stage of Zenit launch vehicles. Glavkosmos lists 740 tf sea-level / 806 tf vacuum thrust, 309/337 s specific impulse, 9,300 kg dry mass, and 4.15 m x 3.565 m dimensions.
- Developers
- Dry Mass Kg
- 9,300
- Family
- Length M
- 4.15
- Lineage
- Note
- NPO Energomash describes RD-171M as the 2002–2004 modification of RD-171 for Zenit.
- Related Propulsion System
- Relationship
- direct-derivative-of
- Sources
- Accessed Date
- 2026-07-29
- Publisher
- NPO Energomash / Samara University repository
- Title
- Modern RD-171M, RD-180 and RD-191 liquid propellant rocket engines: program status and perspectives
- Manufacturers
- Propellants
- liquid oxygenkerosene
- Rocket Specs
- Chamber Count
- 4
- Cycle
- oxidizer-rich staged combustion
- Sea Level Specific Impulse S
- 309
- Sea Level Thrust Kn
- 7,257
- Vacuum Specific Impulse S
- 337
- Vacuum Thrust Kn
- 7,904
Links
Assets & Meta
- Creation Time
- July 29, 2026 at 09:56:22 UTC
- Updated Time
- August 20, 2026 at 12:16:18 UTC
Other
- Diameter M
- 3.565
- Sources
- Accessed Date
- 2026-07-29
- Publisher
- NPO Energomash / Samara University repository
- Title
- Modern RD-171M, RD-180 and RD-191 liquid propellant rocket engines: program status and perspectives
- 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
- Zenit-3SL official vehicle reference
- Accessed Date
- 2026-07-29
- Publisher
- Production Association Yuzhny Machine-Building Plant
- Title
- Anniversary of the Energia–Buran project
- Accessed Date
- 2026-08-20
- Note
- Official Glavkosmos product table identifies RD-171M as a four-chamber oxygen/kerosene engine with 740 tf earth thrust, 806 tf void thrust, 309/337 s earth/void specific impulse, 9,300 kg dry weight, and 4,150 mm by 3,565 mm dimensions.
- Publisher
- Glavkosmos
- Title
- RD-171 M - Liquid-fuel Rocket Engine