UFO files: secret US spy plane Aurora could be behind sightings A number of UFO sightings may have been caused by a secret US spy plane called Aurora, the existence of which has never been officially admitted, according to files released on Monday. Published: 8:00AM BST 17 Aug 2009 More than 70 witnesses including police and military personnel reported sightings in Devon, Cornwall, South Wales and Shropshire in the early hours of Wednesday March 31, 1993, with many describing a large, low-flying object which made a low humming sound. In a briefing note to the Assistant Chief of the Air...