These sightings began in 1989 but peaked with the events on 30/31 March 1990. On that night several unknown objects were tracked by two Belgian aircrafts and photographed. Additionally, they were witnessed by around 13,500 people with 2,600 filing official written statements detailing what they saw. The general description of the sighting is of three unusual lights, brighter than stars and changing colour, flying across the sky towards the South-East of Brussels. Patrols of Belgian aircraft were sent to investigate and try to track the lights, which had formed into small triangles. They managed to obtain a radar lock onto the unidentified crafts on three occasions, but their targets rapidly accelerated each time before descending to ground level. The pilots never made visual contact with the targets. The sudden changes in speed of the unidentified crafts should have been fatal to their pilots. Ground witnesses, the police and the pilots all give identical accounts of this sighting.
Many people are sceptical about these sightings, mainly because the only photo to emerge from the wave turned out to be a hoax. A lot of people explain the sightings as mass delusion, from misinformation spread by the media and the UFO logical organisation. Others argue that they were simply helicopters, their silence explained by a strong natural wind, or other noise drowning their engine sound out. However, nothing has been confirmed or verified, and the Belgian UFO Wave remains unexplained.
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