Airliner had near miss with UFO
Civil Aviation Authority and military investigations could not explain the 1991 incident near Lydd in Kent.
The unsolved close encounter features in UFO-related military documents made available by the National Archives.
After ruling out the object flying past the Alitalia jet being a missile, weather balloon or space rocket, the MoD closed the inquiry.
Nineteen files covering sightings between 1986 and 1992 are being made available online.