A passenger aircraft had a narrow miss with an unidentified object over Glasgow, a report has revealed.
The Airbus A320 was making its final approach to Glasgow Airport on 2 December when an object passed about 300ft underneath it.
The pilot of the aircraft said the risk of collision with the object, which did not show up on radar, had been "high".
A report by the UK Airprox Board said investigators were unable to establish what the object had been.
The A320 was flying with its landing lights on, in clear conditions and at an altitude of about 4,000ft above the Baillieston area of Glasgow, when the pilot and non-flying pilot of the aircraft saw an object "loom ahead" at a range of about 100m.
The object passed directly beneath the aircraft before either of the crew members had time to take avoiding action or had "really registered it", although they both agreed that it appeared to have been blue and yellow or silver in colour with a small frontal area, but that it was "bigger than a balloon".
The pilot asked the controller at Glasgow Airport if he was "talking to anything in the area" as he had "got quite close" to a blue and yellow aircraft, travelling in the opposite direction, which had passed just below him.
The controller stated that he was not talking to anyone else in that area and that nothing was seen on radar.
The Airprox report included a transcript of the conversation that took place between the aircraft and the controller at 12:55:
A320: "Glasgow Approach [A320 C/S]"
EGPF: "[A320 C/S] pass your message"
A320: "Er yeah we just had something pass underneath us quite close [1255:30] and nothing on TCAS have you got anything on in our area"
EGPF: "Er negative er we've got nothing on er radar and we're n- not talking to any traffic either"
A320: "Er not quite sure what it was but it definitely er quite large [1255:40] and it's blue and yellow"
EGPF: "OK that's understood er do you have a an estimate for the height"
A320: "Maybe er [1255:50] yeah we were probably about erm four hundred to five hundred feet above it so it's probably about three and a half thousand feet."
From the BBC (http://www.bbc.co.uk...w-west-22365368)