NERVA XE-Prime experimental engine
XE-Prime was the NERVA experimental nuclear-thermal engine tested in a flight-type arrangement with a close-coupled hydrogen feed system. Its hot-bleed cycle drove the turbopump, while the reactor heated hydrogen for thrust. The Rover test history records firings from 4 December 1968 to 11 September 1969 and 24 separate startups. Testing investigated control sequences, restart from different thermal and pump-inlet conditions, pulse cooling and remote engine handling at Engine Test Stand 1 in Nevada. Its reported 1,140 MW rating is reactor thermal power, not electrical output. XE-Prime remained a ground experimental engine.
Identity
- Aliases
- XE-PrimeXE PRIMENERVA XE
- Domains
- spaceflight
- Identity Level
- variant
- Kind
- other
- Name
- NERVA XE-Prime experimental engine
- Status
- historical
Details
- Description
- XE-Prime was the NERVA experimental nuclear-thermal engine tested in a flight-type arrangement with a close-coupled hydrogen feed system. Its hot-bleed cycle drove the turbopump, while the reactor heated hydrogen for thrust. The Rover test history records firings from 4 December 1968 to 11 September 1969 and 24 separate startups. Testing investigated control sequences, restart from different thermal and pump-inlet conditions, pulse cooling and remote engine handling at Engine Test Stand 1 in Nevada. Its reported 1,140 MW rating is reactor thermal power, not electrical output. XE-Prime remained a ground experimental engine.
- Family
- First Run Date
- 1968-12-04
- Propellants
- liquid hydrogen
- Rocket Specs
- Cycle
- Nuclear-thermal hot-bleed cycle
- Restartable
- Yes
Links
- Official Url
- https://ntrs.nasa.gov/citations/19920005899
Assets & Meta
- Creation Time
- October 29, 2026 at 16:06:00 UTC
- Updated Time
- October 29, 2026 at 16:06:00 UTC
Other
- Sources
- Accessed Date
- 2026-10-29
- Note
- XE-Prime section: 4 December 1968–11 September 1969 test series, 24 separate startups, hot-bleed cycle, flight-type configuration and 1,140 MW reactor rating. No thermal-power value interpreted as electrical power.
- Publisher
- NASA / Sverdrup Technology
- Title
- Rover Nuclear Rocket Engine Program: Overview of Rover Engine Tests