UNCLASSIFIED // PUBLIC RELEASERELEASE 06 · SEPTEMBER 18, 2026
PENTAGON UFO FILE · DOCUMENT · DOW-UAP-D123AAWSAP DIRD, Positron Aerospace Propulsion, March 2010
This Defense Intelligence Reference Document, dated March 2, 2010, looks at one of the most exotic propulsion ideas in the AAWSAP series: using positrons, the antimatter counterparts of electrons, as fuel. It was produced for the Defense Intelligence Agency within the Pentagon’s Advanced Aerospace Weapon System Applications Program and is a technology study with no connection to particular sightings.
The promise and the catch
The attraction is energy density. When a positron meets an electron the two annihilate and their mass is converted into energy, far more per kilogram than any chemical or nuclear fuel releases. On that basis the paper sketches a wide range of uses: aircraft and missiles with very long endurance, launch vehicles that reach orbit in a single stage, onboard power plants and crewed missions to Mars.
The catch, which the paper does not hide, is supply. It treats as unsolved both how to make positrons in useful quantities and how to keep them safely stored for long periods, and much of its discussion of vehicles and Mars missions is conceptual rather than grounded in demonstrated engineering.
How to read it
The release’s summary judges positron propulsion attractive in theory and highly speculative in practice, because its two basic requirements remain unsolved. A DIRD collects existing knowledge for analysts and is not an endorsement; the release cautions that the summary reflects the paper’s framing at the time. A paper on a different deep-space approach from the same month is the series’ advanced nuclear propulsion study.
The official description
From war.gov/UFO, released September 18, 2026, quoted in full
This document is a Defense Intelligence Reference Document (DIRD), a technical reference format used by the Defense Intelligence Agency (DIA) to capture baseline knowledge on a specific topic for later analytic use. DIRDs are best understood as reference and synthesis products rather than as original research. It is one of 38 DIRDs produced under the Advanced Aerospace Weapon System Applications Program (AAWSAP) between 2009 and 2011. Because AAWSAP’s scope permitted a broad range of supporting topics, not every DIRD in the series directly concerns aerospace systems or future threat assessment. The following summary reflects the DIRD’s scope and framing at the time of writing and should not be read as implying current validation of the concepts discussed.
This DIRD examines positrons as a possible fuel for advanced aerospace propulsion, arguing that antimatter offers extraordinary energy density and could, in principle, support applications ranging from long-endurance aircraft and missiles to single-stage launch vehicles, onboard power systems, and crewed Mars missions. At the same time, it makes clear that the concept depends on resolving major unsolved problems in producing positrons in sufficient quantities and storing them safely for long periods, and much of the document’s discussion of flight systems and Mars missions remains conceptual rather than closely tied to demonstrated engineering practice. Its overall conclusion is that positron propulsion is theoretically attractive, but remains highly speculative as a practical technology because its core production and storage requirements remain unsolved.