From 2008 to 2013, the UK National Archives released the Ministry of Defence’s UFO files to the public in six tranches. The final release came in June 2013 — the closure documents of the MoD’s UFO Desk, which was quietly shut down in November 2009 after receiving the largest number of UFO sighting reports in thirty years. What follows is the complete record of what was released, what series to search, and the critical fact that most of what the MoD collected before 1967 no longer exists.
The Destruction Policy: What Was Lost Before 1967
Until 1967, the Ministry of Defence’s policy was to destroy all UFO files at five-yearly intervals. This means that every sighting report, every internal assessment, every correspondence relating to UFOs from 1950 to approximately 1965 was systematically shredded on schedule. Official recording of UFO sightings began in the early 1950s. Nearly fifteen years of that record was destroyed by policy before the retention decision was made in 1967.
Since 1970, surviving MoD UFO files have been reviewed for eventual public release. What the TNA holds is what escaped the five-year destruction cycle — primarily records from 1967 onwards, with some earlier material that was retained for ongoing investigations.
The Six Tranches: 2008–2013
The National Archives released MoD UFO files in the following tranches. All are searchable via the TNA Discovery catalogue at discovery.nationalarchives.gov.uk using keywords “UFO”, “unidentified flying” or “saucers” in the DEFE, AIR, FCO and BJ series.
- 2008 — First tranche: Initial release of MoD sighting reports and correspondence
- 2009 — Second tranche: Further DEFE 24 series files
- 2010 — Third tranche: Expanded correspondence and parliamentary questions
- 2011 (August) — Fourth tranche: DEFE 24/1958/1, 2006/1, 2019/1, 2020/1, 2031/1, 2033/1, 2034/1, 2035/1, 2047/1, 2056/1 and additional files
- 2012 — Fifth tranche: Further DEFE 24 series files
- 2013 (June) — Final tranche: 25 files covering the MoD UFO Desk’s final two years (2007–2009) and its closure
The Final Tranche: Closure of the MoD UFO Desk
The June 2013 release is the most significant. It contains documents, drawings, letters, photographs and parliamentary questions covering November 2007 to November 2009 — the final two years of the MoD UFO Desk before it was closed. The 25 files in this release are:
DEFE 24/2448/1 through DEFE 24/2465/1 and DEFE 24/2623/1 through DEFE 24/2629/1.
The closure of the UFO Desk in November 2009 was itself significant. It came after the MoD received the largest volume of UFO reports in thirty years — not the smallest. The official reason given was resource allocation. The files in this final tranche document the internal debate about closure, the public disclosure campaign that the closure triggered, and the handling of the report surge that preceded it.
What the Series Contain
- DEFE 24 — The primary UFO series. Hundreds of files covering sighting reports, internal assessments, correspondence and policy documents from the 1950s to 2009
- AIR 2 — Air Ministry correspondence. Includes AIR 2/19086: UFO policy and policy statements 1970–1971
- FCO — Foreign and Commonwealth Office. Diplomatic correspondence relating to UAP, including international sighting reports and allied government exchanges
- BJ — Joint Intelligence Committee records with UAP-related content
Online Access: 1950–2002
UFO reports and correspondence from 1950 to 2002 are available to browse online via the TNA’s archived webpage at webarchive.nationalarchives.gov.uk/ukgwa/+/https://www.nationalarchives.gov.uk/ufos/. These are digitised and do not require a visit to Kew.
Records from 1950 to 1995 not yet digitised — covering UFO reports, correspondence and parliamentary business — require an in-person visit to The National Archives at Kew, Richmond, TW9 4DU, or a paid remote research service.
The Expert: Dr David Clarke
The National Archives’ official UFO expert is Dr David Clarke, journalist, academic and author of The UFO Files, which combines government reports with eyewitness interviews. Clarke guided TNA’s video release of the final June 2013 tranche and has written the official research guides to the collection. His blog post “Do you believe in UFOs?” documents the background to the file releases and is accessible via the TNA blog.
The Oracle Assessment
The destruction policy that ran until 1967 is the defining fact of the UK UFO record. Everything the RAF, MoD and related agencies collected during the most active period of UAP sighting reports — the late 1940s through the mid-1960s, including the Lakenheath-Bentwaters incident of 1956 — was routinely shredded. What survived did so because the retention policy changed, not because it was preserved by design.
The US destroyed nothing equivalent because its records were folded into Project Blue Book’s institutional structure. The UK destroyed on a five-year cycle by explicit policy. That asymmetry matters when comparing what the two governments publicly hold.
The FCO series has received the least public attention. Diplomatic UAP correspondence — exchanges with allied governments, reports from British embassies on UAP incidents in their host countries — is in those files. That is the thread worth pulling.
Sources: The National Archives, nationalarchives.gov.uk/help/with-your-research/research-guides/ufos. UK Government Web Archive, webarchive.nationalarchives.gov.uk. Dr David Clarke, TNA expert.