GRC Heat Pipe / Kilopower / Fission Surface Power¶
FO-validated heat pipe technology became the thermal transport core of NASA's flagship fission power program.
Created: Session 97, 2026-04-07
Last updated: Session 97, 2026-04-07
Summary¶
Two Flight Opportunities projects at Glenn Research Center validated heat pipe behavior in reduced gravity. The same PI (Marc Gibson) carried this thermal transport technology into the Game Changing Development Kilopower program, which successfully demonstrated a fission reactor in 2018. Kilopower then transitioned to the Tech Demo Missions Fission Surface Power (FSP) project — a $15M+ multi-contractor effort targeting a 40 kWe lunar reactor by the early 2030s.
This is one of FO's strongest program transition cases: FO → FO → GCD → TDM, with the same PI threading through three of four stages and TechPort explicitly confirming the infusion.
FO Projects¶
12184 — Heat Pipe Limits in Reduced Gravity Environments¶
| Field | Value |
|---|---|
| Lead Org | Glenn Research Center |
| PI | Marc A. Gibson |
| Period | 2011-09-07 to 2015-05-07 |
| TRL | 4 → 6 |
| Status | Completed |
| TX | TX03.1.4: Dynamic Energy Conversion |
What it tested: Thermosyphon flooding limits in reduced gravity. Titanium-water heat pipes for fission power system radiators need gravity-dependent flooding models validated in actual microgravity. This data was nonexistent prior to these flights.
Flight tests: Parabolic flights (reduced-gravity aircraft).
Key publications: - NASA/TM-2013-217905: "Thermosyphon Flooding in Reduced Gravity Environments Test Results" - NASA/TM-2013-216536: "Thermosyphon Flooding in Reduced Gravity Environments" - Conference paper (2012): "Thermosyphon Flooding in Reduced Gravity Environments"
TechPort note: Description states "This work continued with a suborbital flight test in 2015 under T0073 Radial Core Heat Spreader."
Data quality issue: technologyOutcomes links to unrelated projects — 146033 (JPL atmospheric sensing) and 91575 (Cornell unsupervised ML). These are erroneous linkages. See TechPort Outcome Data Quality.
93976 — Radial Core Heat Spreader¶
| Field | Value |
|---|---|
| Lead Org | Glenn Research Center |
| PI | Marc A. Gibson |
| Period | 2014-09-01 to 2015-09-30 |
| TRL | 5 → 6 |
| Status | Completed |
| TX | TX03.1.4: Dynamic Energy Conversion |
| Destination | Mars |
What it tested: A Radial Core Heat Spreader (RCHS) using titanium structure and capillary wick with water working fluid. This passive thermal control system couples Stirling convertors to heat rejection systems, providing up to 10x thermal conductance improvement.
Flight test: Black Brant IX sounding rocket, launched July 7, 2015. Two identical RCHS units flown — one horizontal, one vertical — to test best and worst case spacecraft configurations.
Infusion confirmed in TechPort description: "This technology has been infused in Kilopower."
Downstream Chain¶
14405 — Kilopower Small Fission Technology (GCD)¶
| Field | Value |
|---|---|
| Program | Game Changing Development (GCD) |
| Lead Org | Glenn Research Center |
| PI | Marc A. Gibson |
| PM | Dionne M. Hernandez-Lugo |
| Period | 2014-07-01 to 2018-10-18 |
| TRL | 3 → 5 |
| Status | Completed |
| Partners | LANL, Y-12 (DOE), Advanced Cooling Technologies, Sunpower, Ohio State, JSC, MSFC |
KRUSTY demonstration: March 20, 2018, at the Nevada National Security Site. 28-hour full-power test using a 28 kg uranium-235 reactor core at 850 C, generating ~5.5 kW fission power. First ground test of a US fission reactor since 1965.
The Kilopower reactor uses passive sodium heat pipes to move heat from the reactor core to Stirling engines for power conversion. The FO-validated heat pipe flooding limits and RCHS thermal performance data directly informed this design.
TechPort outcome: "Advanced To → Fission Surface Power [105671]" (Oct 2019)
105671 — Fission Surface Power (TDM)¶
| Field | Value |
|---|---|
| Program | Tech Demo Missions (TDM) |
| Lead Org | Glenn Research Center |
| PM | Lindsay K. Kaldon |
| Period | 2019-10-01 to 2028-09-30 |
| TRL | 4 → 8 (target) |
| Status | Active |
| Destinations | Moon, Mars |
| View Count | 5,568 |
Objective: Design, build, and qualify an engineering flight unit for a minimum 10 kWe fission power system, demonstrable on the lunar surface. Four 10 kWe units could power robust operations on the Moon and Mars.
Phase 1 contracts (June 2022): Three $5M contracts from DOE/INL: - Lockheed Martin - IX (Intuitive Machines + X-Energy JV) - Westinghouse
Phase 1 extended in early 2024 for continued design optimization. Phase 2 solicitation expected 2025.
Other partners (TechPort): Aerojet Rocketdyne, BWX Technologies, Boeing, Creare, DOE, Maxar
USASpending contracts found: | Contractor | Award ID | Amount | Period | Description | |-----------|----------|--------|--------|-------------| | Sunpower | NNC09CA23C | $6.42M | 2010-2015 | Full-scale power conversion unit | | Brayton Energy | 80GRC024CA003 | $1.0M | 2023-2025 | FSP Advanced Closed Brayton Convertor | | Rolls-Royce NA | 80GRC024CA004 | $999K | 2023-2024 | FSP Advanced Closed Brayton Convertor | | GE | 80GRC024CA005 | $900K | 2023-2024 | FSP Advanced Closed Brayton Convertor | | Ultramet | NNX09CA52C | $600K | 2009-2011 | High-temp foam core heat exchanger for FSP |
Total tracked NASA/DOE investment: $15M (Phase 1) + $9.9M (USASpending contracts above) + KRUSTY costs = $25M+ and growing
Timeline¶
| Year | Event | Program |
|---|---|---|
| 2011-2015 | Heat pipe flooding limit parabolic flights | FO |
| 2014-2015 | RCHS sounding rocket flight (Black Brant IX, Jul 2015) | FO |
| 2014-2018 | Kilopower development; KRUSTY demo Mar 2018 | GCD |
| 2019 | FSP project established | TDM |
| 2022 | Phase 1 contracts to Lockheed, IX, Westinghouse ($15M) | TDM |
| 2024 | Phase 1 extended | TDM |
| 2025 | Phase 2 solicitation expected | TDM |
| Early 2030s | Target lunar deployment | TDM |
Gap: ~17 years from first FO flight (2011) to target deployment (early 2030s). This is consistent with nuclear technology's long maturation cycle, not a stall.
Verification¶
| Claim | Evidence | Confidence |
|---|---|---|
| FO validated heat pipe flooding limits in microgravity | 3 NASA technical reports (TM-2013-217905, TM-2013-216536, 2012 paper) | Confirmed |
| RCHS flew on sounding rocket | TechPort [93976] description: "launched on a Black Brant IX sounding rocket on July 7, 2015" | Confirmed |
| RCHS technology infused into Kilopower | TechPort [93976] description: "This technology has been infused in Kilopower" | Confirmed |
| Kilopower transitioned to FSP | TechPort outcome linkage [14405] → [105671] | Confirmed |
| Same PI across FO → GCD | Marc A. Gibson on [12184], [93976], [14405] | Confirmed |
| Phase 1 FSP contracts = $5M each | NASA press release June 2022 + web sources | Confirmed |
| Heat pipes are core Kilopower thermal transport | Wikipedia, NASA press releases, NTRS publications | Confirmed |
Related Pages¶
- FO Mission Infusion Summary — listed under Program Transitions
- Creare LAD — another FO cryogenics/thermal project with cross-program connections
- Teledyne Energy HEPS — another FO power generation technology
- TechPort Outcome Data Quality — documents erroneous linkages found on [12184]
Open Threads¶
- What was Marc Gibson's specific role in KRUSTY? Lead engineer (per web sources) — worth confirming
- Did the FO heat pipe data feed into the SBIR contracts with Advanced Cooling Technologies (9593, 16158, 17879, 34095)?
- What is the total FSP program budget? Phase 1 alone was $15M, but the full program through 2028 is likely $100M+
- How much of the RCHS design specifically carried into FSP vs. the sodium heat pipes used in Kilopower (different working fluid — water vs. sodium)?