UK MoD UAP Files — National Archives Mass Release (2008–2012)

Between May 2008 and June 2012, the UK Ministry of Defence released its UAP investigation files to the National Archives in a series of annual batches, totaling over 6,700 pages covering the period 1978–2007. The releases were prompted by Freedom of Information requests and a government decision to transfer the MoD's UAP investigation function (Directorate of Air Staff Secretariat, DAS) to a formal archive. The files included: RAF pilot encounter reports with radar data; MoD Defence Intelligence Staff (DI55) assessments of credible cases; public letters and reports from civilian witnesses; police and coastguard reports; and internal MoD memos discussing the scientific and security implications of UAP. The MoD's own internal assessment documents acknowledged that some UAP reports came from highly credible witnesses, involved physical effects, and resisted conventional explanation. One DAS internal memo stated that the MoD took UAP seriously as a potential air defence concern. Nick Pope, who ran the MoD's UAP desk (Secretariat Air Staff 2a) from 1991–1994, publicly confirmed the MoD's position that a small percentage of cases were genuinely unexplained. The complete released archive is publicly accessible at the UK National Archives (TNA) at Kew under reference series DEFE 24.