Sea of Japan: Navy P2V paced by 10 UFOs
On April 14, 1953, a U.S. Navy P2V Neptune on an ELINT mission over the Sea of Japan was approached and harassed by ten highly agile unidentified objects. The UFOs made over 70 close passes, emitted Morse code 'D' signals, and were tracked by radar and electronic systems for over two hours.
Background
Incident
On April 14, 1953, between 21:23 and 23:50, a US Navy P2V Neptune reconnaissance aircraft flew an electronic intelligence mission over the Sea of Japan, about 320 kilometres southeast of Vladivostok, Russia. The aircraft was operating at only 120 metres above the sea.
Encounter
Ten agile, highly manoeuvrable unidentified objects circled and harried the aircraft. They made more than 70 aggressive passes, including high-speed runs, many directly beneath the P2V at a distance of a few hundred metres. The objects held distances of as little as 120 metres and remained active for over an hour.
Observations and Evidence
The objects sent light signals in Morse code (the letter "D"), a unique occurrence. They were detected by radar and by Navy ELINT systems, which analysed the objects' radar emissions. The pursuit lasted about an hour and a half.
Significance
The case is regarded as a precisely documented military UAP contact of the Cold War, with several types of evidence: visual, radar, and signals intelligence.