"There is ample literature on the UFO sightings in Belgium during the night of March 30-31, 1990, at the height of the so-called Belgian UFO wave. While the events unrolled, two F-16 jets were scrambled over the Perwez-Ramillies area to investigate. There was a radar lock-on (unknown echoes detected) from the aircraft, yet pilots did not see anything visually.
It is now pertinent to recall to our readers which are probably the most extensive sources about this series of much-debated events: Auguste Meessen, "Observations, analyses et recherches", in Vague d'OVNI sur la Belgique Volume 2, SOBEPS (Bruxelles), 1991, pages 387-430. Auguste Meessen, "Analyses approfondie des mystérieux enregistrements radar des F-16", Inforespace, 97, December 1998, pages 9-48. Tim Printy, "March 30-31, 1990 -- The Belgium -16 UFO Chase", http://home.comcast.net/~tprinty/UFO/..., pages 5-9. Roger Paquay, "The evening of 30 March 1990: Observation by the F16s", ibid, pages 10-14.
Thanks to the generosity of Franck Boitte, I have received the original tape recorded by the military aircraft containing the footage acquired by the onboard radar. The NTSC recording -stored in a large U-MATIC videocassette- has been converted into plain MP4 video format, and I am happy to display here the 2.14 minute footage for all to watch and retain, once it has been uploaded to YouTube for quicker, general downloading and access.
Apparently, the cause for the radar echoes was either any abnormal atmospheric conditions or rather an artifact from the own radar equipment, i.e., the creation of false radar targets or returns with unusual rates of speed. (I wish to thank Manuel Borraz for key assistance.)"