On the night of 19 September 1976 residents of northern Tehran began ringing Mehrabad airport: a bright object was standing over the city. The Iranian Air Force scrambled an F-4 Phantom; as it closed, its communications and instruments failed and it turned away. A second was sent up, locked the target on radar, and when it tried to fire, the weapons system and radio failed and the pilot broke off. By the crew's report a smaller object separated from the first, went down and landed, flooding the ground with light. The American defence attaché's report on the case was circulated to the State Department, the CIA, the NSA and the Defense Intelligence Agency, and has long been declassified. It is among the best-documented military episodes in the subject.

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The Berwyns and the Welsh Roswell

On the evening of 23 January 1974 the ground shook in the Berwyn mountains of north Wales and lights were seen on the hillside. People assumed an aircraft had come down; police, a nurse and mountain rescue climbed in the dark and found nothing. Over the years the story acquired military lorries carrying containers away, and the nickname the Welsh Roswell. Seismic records show a real earthquake of about magnitude 3.5 that evening, and the lights fit well with a bright fireball seen across northern Britain in the same minutes. The coincidence of two events in one evening produced everything else.