Condign Uncovered: The UK MOD's Secret Aerial Phenomena Study and FoIA Revelations
To the point
Ron Haddow authored a UK MOD study on unidentified aerial phenomena that hinted at secret US programs named Aurora/Astra and Black Manta and suggested exotic aircraft might have crossed UK airspace, but there is no conclusive evidence those programs existed and many sightings were hoaxes or misidentifications.
