A few days late, but I've just come across this on the website of Eric Joyce, the Independent (formerly Labour until an unfortunate incident in the Strangers Bar at the House of Commons) MP for Falkirk. He says on his site "share this", so I will:
"There's a slew of stuff in the papers today [21 June 2013] about the eventual closure of the RAF’s ‘UFO’ desk. Most of the copy is the funny stuff, folk being abducted and so forth. Then there’s some thoughts behind the occasional surge in reports from the public – the increased use of Chinese lanterns and the movie Close Enounters, for example. 🔻
"The reports might have mentioned that there would have been another reason for the occasional upsurge in reports – that is, that they were real.
"This Daily Mail reports from 2009 makes the point neatly. When Stealth bombers were being developed, they routinely flew over the airspace of friendly nations – certainly including the UK and Scotland. Indeed, over the years, experimental aircraft of all sorts, usually secret, would have been seen by the public and MoD assets (including US airbases in the UK) on the ground would have tracked them. Given that many such flights were secret, the MoD would presumably at the time have given the usual wacky reasons re: UFO sightings.
"The MoD would also have wanted to check genuine sightings to ensure they were what they thought they were – i.e. the US or ourselves, and not either the US doing something cheeky we hadn’t been told about or, even more ‘of interest’, some other nation like the (then) Soviets being even more cheeky. That stuff will still be going on, although with the end of the Cold War the spend on ‘invisiblity’ re: aircraft is probably well down, along with sightings of experimental aircraft. Unless you live in Arizona, or some such.
"Not all UFOs were full of little green men and women."