Calvine UFO Incident — DEFE 24/1940 (Sec(AS) briefing on August 1990 Perthshire diamond photograph)

Brief

In August 1990, two civilian witnesses near Calvine, Perthshire, photographed a large stationary diamond-shaped UAP in apparent proximity to an RAF Harrier; the photographic negatives were passed to the MoD and never returned. The Sec(AS)2 handwritten briefing summary that forms the file's analytical core is not among the 34 pages with extractable text, leaving the primary MoD assessment inaccessible from this release. The 159-page file bundles a collection of standardized SOP 502 sighting forms from late 1990 covering geographically distinct incidents across England and Scotland. A surviving colour print from the Calvine photographs was rediscovered by researcher Dr. David Clarke in 2022.

Metadata

Agency

UK Ministry of Defence / Secretariat Air Staff

Release

2008-10-08

Type

PDF • .pdf

Length

159 pages

Classification

UNCLASSIFIED

Programs

Sec(AS)2, SOP 502

Tags

diamond-shaped craft, stationary hover, RAF Harrier proximity, still photography, Perthshire Scotland, 1990, negatives withheld, Sec(AS)2 briefing, SOP 502

Key points

• Two civilian witnesses in August 1990 near Calvine, Perthshire photographed a large stationary diamond-shaped craft in proximity to an RAF Harrier jet — a configuration unique among UK MoD UAP records.
• Photographic negatives submitted to MoD after the Calvine sighting were retained and never returned to the witnesses.
• A colour print from the Calvine photographs was rediscovered by researcher Dr. David Clarke in 2022, more than three decades after the incident.
• The Sec(AS)2 handwritten briefing — the file's nominal analytical core — does not appear in the 34 extractable pages; the primary MoD assessment is effectively withheld by image quality or redaction.
• A SOP 502 report dated approximately 12 November 1990 describes 2-3 lights converging into an object shaped 'like concorde,' observed for 1-2 minutes, moving in multiple axes before disappearing behind houses in a built-up area.p.22
• A two-night sighting from 7-8 November 1990 describes blue, red, and white flashing lights hovering approximately 10 miles off the coast at Hartlepool, observed through binoculars from a hill overlooking the sea.p.51
• A 5 December 1990 report logs red and blue lights stationary over the Thames estuary at 10-15 degrees above the horizon, observed through binoculars in clear conditions at 2315Z.p.36
• One SOP 502 form describes an 'extremely large object' of semi-circular/parabolic form moving from north to south before becoming stationary, observed through a magnified optical device over Northumberland.p.60

Verbatim

• 2 - 3 Set lights getting brighter coming together to form shape like concorde

  p.22

• Red and Blue lights over Thames estuary to the south.

  p.36

• 10-15 degrees above horizon.

  p.36

• Series of blue red & white flashing lights moving Slowly above the horizon

  p.51

Most interesting

• The Calvine photograph is regarded by researchers as the clearest UAP image ever submitted to the UK MoD — the diamond-shaped craft appeared large enough, and the flanking RAF Harrier identifiable enough, that misidentification of scale was not a plausible explanation.
• Dr. David Clarke, a Sheffield Hallam University researcher who worked with UK MoD UAP files for years, reportedly found the surviving colour print misfiled among general administrative records at the National Archives rather than in the main UAP case file.
• The SOP 502 Annex A form used throughout this file was a standardized UK military intake protocol requiring observers to document eleven discrete parameters, including angle of sight, distance relative to a known landmark, and meteorological conditions — evidence of a systematic national collection architecture.
• The Hartlepool offshore sighting spans two consecutive nights — 7 and 8 November 1990 — making it atypical among the SOP 502 reports in this file, most of which cover single-observation events.
• The file's 159 pages for what began as a single incident suggest the MoD treated Calvine as an active dossier, accumulating secondary reports and correspondence rather than closing it as a one-off sighting.
• Three geometrically distinct UAP forms appear across the extractable pages alone — the Calvine diamond, the concorde-shaped converging lights of page 22, and the semi-circular/parabolic object of page 60 — within a single four-month window over the UK.