NASA Technical Reports Server (NTRS), 2026-10-09 (Investigator, Step I, run 1)

Site: https://ntrs.nasa.gov (search API and PDF downloads by curl; one result first seen through Google).

Queries: NTRS API "Twenty First Century Propulsion Concept" (0 results), Talley Biefeld-Brown (0 results), asymmetrical capacitor thrust (5 results: 20020076454 and 20010125606, Campbell patent "Apparatus ... Two Dimensional, Asymmetrical Capacitor Module"; 20040120932, "Cylindrical Asymmetrical Capacitor Devices for Space Applications"; 20040085936, "The ISR Asymmetrical Capacitor Thruster: Experimental Results and Improved Designs"; 20040171929, "Asymmetrical Capacitors for Propulsion" = NASA/CR-2004-213312, already in the folder). Google led to 20040171466 (NASA/TM-2004-213283).

Saved in research/files/: - NASA-MSFC-Campbell-2004-barrel-shaped-asymmetric-capacitor-NTRS-20040171466.pdf - NASA-NTRS-20040085936-ISR-asymmetrical-capacitor-thruster-experimental-results.pdf - NASA-NTRS-20040120932-cylindrical-asymmetrical-capacitor-devices.pdf (US 6,775,123 B1)

Result: positive (related work and test records for claim 1; Naudin's page "Replication of the NASA 2D Asymmetrical Capacitor Thruster" in the folder replicates Campbell's patented 2D module).

NASA/TM-2004-213283, "NASA Marshall Space Flight Center Barrel-Shaped Asymmetrical Capacitor" (June 2004)

[web] https://ntrs.nasa.gov/api/citations/20040171466/downloads/20040171466.pdf . Authors J.W. Campbell, M.R. Carruth, D.L. Edwards, A. Finchum, G. Maxwell, S. Nabors (MSFC), L. Smalley (UAH), D. Huston, D. Ila, R. Zimmerman, C. Muntele, I. Muntele (Alabama A&M). Rotating test rig (typical 27 kV, 60 rpm). Section 6 "Vacuum testing and results". Summary and conclusions (p.45): the device "obeys the laws of physics as currently understood including MHD equations, conservation of momentum, Coulomb's law, and Newton's laws of motion ... No NACAP performance was observed in vacuum, implying reduced thrust levels as the numbers of potential charge carriers were reduced." It also cites an earlier investigator who "found that at 19 kV there was no detectable thrust in vacuum", "one of several independent investigations".

Canning (ISR), Cole and Campbell (MSFC), Winet (ISR), AIAA Joint Propulsion Conference, July 2004

[web] https://ntrs.nasa.gov/api/citations/20040085936/downloads/20040085936.pdf . Devices tested in air, argon and nitrogen, at atmospheric pressure and at reduced pressure; VHF radiation from Trichel pulses correlated with current; sharp leading features plus sharp trailing wires gave the most thrust; thrust direction usually followed geometry, not polarity. "While no force was measured in a vacuum, some suggested design changes are given for operation in reduced pressures."

US 6,775,123 B1 (Campbell, NASA), "Cylindrical asymmetrical capacitor devices for space applications" (10 Aug 2004)

[web] https://ntrs.nasa.gov/api/citations/20040120932/downloads/20040120932.pdf . The inventor's text says of his earlier 2D-module patents: "Thrust is substantially and significantly reduced in vacuum"; the new embodiments add a dielectric shroud "provided with gas to allow operation in vacuum". Claim 1 nonetheless reads "An asymmetrical capacitor system for creating a thrust in a vacuum". This is NASA's own patent position: thrust in space needs a supplied gas.

How it bears on claim 1: three NASA-linked records (MSFC TM, ISR AIAA paper, Campbell patent) report no measured vacuum force or strongly reduced vacuum thrust, alongside Naudin's account of the Gravitec video (rotation at 1.72e-6 Torr, 45 kV, "NSSTC LEEIF vacuum chamber"). The Gravitec test was also at NSSTC/Huntsville; whether it shared people or apparatus with the MSFC programme is a question for the next run. Talley's Air Force reports were not found in NTRS (they are Air Force, not NASA, reports).