Latest: Release 07, Fri 23 Oct 2026Next release: estimated Fri 20 Nov 2026 (window 13 Nov to 4 Dec)

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RELEASE 06 / DOW-UAP-D152

DOW-UAP-D152, AAWSAP DIRD, Negative Mass Propulsion, January 2011

File ID
DOW-UAP-D152
Agency
Department of War
Release
Release 06, 18 Sep 2026
Event date
1/3/2011 (read as 3 Jan 2011; precision: day)
Location
Las Vegas, Nevada
Type
PDF
Redactions
Yes, parts of the official copy are blacked out

The official record

Official copy at war.gov
First page of the official copy

Official summary, as published

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 whether negative mass could exist in a physically meaningful way and whether it could someday reduce the energy cost of spaceflight. The report reviews the unusual dynamics that would follow if positive and negative mass could interact, including self-accelerating mass pairs and matter with very low or nearly zero effective inertia, and treats such ideas as at least formally compatible with certain extensions of gravitational theory. It then considers two broad paths toward practical use: creating or separating negative mass through extreme fields or particle energies, and locating naturally separated negative matter in deep gravitational wells such as galactic centers or possibly the Moon. However, the document also concludes that the first path is effectively beyond technical reach and treats the second as highly uncertain, resting on a long chain of unverified assumptions about the existence, separability, and macroscopic behavior of negative mass. Overall, this DIRD is a far-reaching theoretical exploration of an exotic propulsion concept whose practical application depends on premises that remain unestablished in consensus physics.

Named in this file

4 names

People, programs and institutions from The Legacy Program research board whose names appear in this file, found by exact spelling against a hand-checked list. A match says only that the file names them, not what part they play. People and programs lists every file that names each one.

Our reading

Reading in progress

We have not published a reading of DOW-UAP-D152 yet. The official summary above is all there is for now.

Our saved copy

Download our saved copy (DOW-UAP-D152_AAWSAP-DIRD-Negative-Mass-Propulsion-January-3-2011.pdf)

One version seen. The checksum lets you confirm that a copy you hold is the one we saved.

  1. First seen

    31.9 MB (33,432,261 bytes)

    SHA-256 de517f7ce71816704e5f989936587eeade1400f339bc0cb01a14733180b41172