Lightning
Firefly Aerospace Lightning is the restartable tap-off-cycle LOX/RP-1 upper-stage engine. The current Alpha specification uses one Lightning engine with 70.1 kN vacuum thrust and 322 s vacuum specific impulse; Firefly 2025 Alpha MK004 guide material reports a 73.0 kN guide figure, so the current published 70.1 kN value is preserved.
Identity
- Aliases
- Lightning 1
- Domains
- spaceflight
- Identity Level
- model
- Kind
- liquid-rocket-engine
- Name
- Lightning
- Status
- active
Details
- Description
- Firefly Aerospace Lightning is the restartable tap-off-cycle LOX/RP-1 upper-stage engine. The current Alpha specification uses one Lightning engine with 70.1 kN vacuum thrust and 322 s vacuum specific impulse; Firefly 2025 Alpha MK004 guide material reports a 73.0 kN guide figure, so the current published 70.1 kN value is preserved.
- Developers
- Manufacturers
- Propellants
- RP-1liquid oxygen
- Rocket Specs
- Cycle
- tap-off
- Restartable
- Yes
- Vacuum Specific Impulse S
- 322
- Vacuum Thrust Kn
- 70.1
Links
- Official Url
- https://fireflyspace.com/alpha/
Assets & Meta
- Creation Time
- July 29, 2026 at 08:54:00 UTC
- Updated Time
- August 15, 2026 at 04:31:05 UTC
Other
- Sources
- 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
- Firefly Alpha launch vehicle family official vehicle reference
- 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
- Firefly Alpha Block II official vehicle reference
- 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
- Firefly Alpha Block I official vehicle reference
- Accessed Date
- 2026-08-14
- Publisher
- Firefly Aerospace
- Title
- Alpha Launch Vehicle current propulsion specification
- Accessed Date
- 2026-08-14
- Publisher
- Firefly Aerospace
- Title
- Alpha Payload Users Guide 5.2