DEFE 31: Defence Intelligence Staff
One level above the desk. Where DEFE 24 holds individual sighting reports, DEFE 31 holds the intelligence assessments: DIS analysts asking what, if anything, decades of accumulated UFO data actually meant. The centrepiece is Project Condign.
Above the Desk
DEFE 24 captures individual reports and desk-level notes. DEFE 31 holds the work of the Defence Intelligence Staff: analysts tasked with looking at the accumulated data and asking harder questions.
The DIS did not investigate individual sightings. Their concern was strategic. Did the pattern of reports reveal anything with defence implications? Were foreign powers testing novel aerospace technology over British airspace? Was there a phenomenon that warranted scientific study? The assessments address these questions directly, drawing on decades of MOD sighting data.
Project Condign. A single DIS analyst, working alone with access to the full body of MOD UFO data, produced a classified study completed in 2000. Title: "Unidentified Aerial Phenomena in the UK Air Defence Region." Several hundred pages. Conclusion: UAP are real physical phenomena but pose no defence threat. The proposed explanation: exotic atmospheric plasma formations, natural but poorly understood. When the report was declassified in 2006, that plasma hypothesis drew immediate criticism from physicists.
The Working Papers
The final report presents conclusions. The working papers show how those conclusions were reached. Which databases the analyst consulted. Which cases were selected as representative. Which hypotheses were tested and abandoned before the plasma theory was settled upon.
The limitations are visible in the papers themselves. One analyst. No peer review panel. Classified, so no external scientific input was possible. The working papers show an intelligence officer applying familiar analytical frameworks to an unfamiliar subject, sometimes effectively, sometimes reaching conclusions the underlying physics could not support.
The plasma hypothesis requires atmospheric plasmas capable of sustained flight, structured appearance, and behaviour that witnesses described as intelligent. No such plasma has been reproduced in a laboratory or definitively observed in the field. Physicists who reviewed the declassified report pointed this out. The working papers do not resolve the tension. They document it.
Condign was one government's attempt to systematically assess UFO data. France's GEPAN programme took a different approach: civilian team, published methodology, laboratory resources. Australia's JIO UFO File contains the Turner briefing, a Five Eyes intelligence assessment reaching different conclusions about US UFO research. British sighting data is on the UK country page.
Document Inventory
| Series | Description | Documents |
|---|---|---|
| DEFE 31 | Defence Intelligence Staff UFO assessments | 4 |
| DEFE 31 | Project Condign final report | 1 |
| DEFE 31 | Condign working papers and analytical notes | Subset |
| DEFE 31 | DIS policy recommendations on UFO reporting | Subset |
External Links
The National Archives Discovery CatalogueA secret Defence Intelligence Staff study conducted between 1997 and 2000 by a single analyst with access to the full MOD UFO reporting archive. The resulting document, "Unidentified Aerial Phenomena in the UK Air Defence Region," ran to several hundred pages and concluded that UAP exist as real physical phenomena. The analyst attributed them to exotic natural plasma formations, poorly understood but not extraterrestrial. The report was classified on completion and remained so until 2006. When declassified, the plasma hypothesis attracted sustained criticism from physicists: no plasma formation with the observed characteristics has been reproduced or documented in controlled conditions, and the report set aside radar and pilot evidence that the plasma model could not account for.
The broader MOD UFO file collection is held in DEFE 24, covering individual sighting reports and desk-level correspondence from 1967 to 2009, including the files from Nick Pope's tenure as desk officer. DEFE 31 draws on that accumulated data to produce the intelligence-level analysis. The Rendlesham Forest incident was among the cases in the DIS data pool that the Condign Report analysed. Browse UK sightings data across all sources in the archive. Flying Saucer Review covered the MOD's internal assessments extensively.
