BRITAIN'S Ministry of Defence investigated a claim that Winston Churchill ordered a cover-up of a UFO sighting during World War II, according to files released by the National Archives.
Documents from the MoD unit assigned to deal with public inquiries about UFOs show that civil servants took seriously a claim that the wartime leader knew about a mysterious craft spotted by an RAF crew.
The allegation came from a member of the public whose grandfather had acted as one of Churchill's bodyguards during the latter stages of the war. The correspondent, whose name has been blacked out from the released files, wrote in August 1999 to ask about an incident over the British coast in the 1940s, when airmen saw a metallic object draw alongside their aircraft and hover near by.
The man said: "My grandfather witnessed the discussion of the event by both Mr Churchill and Mr (Dwight) Eisenhower in the United States, and the great concern that it caused in both countries.
"During the discussion with Mr Churchill, a consultant dismissed any possibility that the object had been a missile, since a missile could not suddenly match its speed with a slower aircraft and then accelerate again.
``Another person at the meeting raised the possibility of an unidentified flying object, at which point Mr Churchill declared that the incident should be immediately classified for at least 50 years and its status reviewed by a future prime minister."
The correspondent urged the MoD not to "dismiss my attempts to pursue this matter as trivial or motivated by 'crackpot' thinking".
The MoD followed his wishes, but was only able to find records relating to Churchill's general interest in UFOs. In 1952 the leader ordered his staff to investigate a flurry of UFO sightings. "What does all this stuff about flying saucers amount to?" he wrote in a memo. "What can it mean? What is the truth?"
A minute in the MoD file observes: "I propose [to] respond robustly, advising that we are unaware of any closed defence records on this subject dating from the time of WWII and referring him to the [Public Record Office - now the National Archives] and Cabinet Office."
The released file is one of more than 3500 cases that came to the attention of the MoD in the period between 1995 and 2003.
None of them was considered evidence of a threat to British airspace, and the UFO unit was closed last year after it became deluged with requests that were made under the Freedom of Information Act.
The unit obliged some correspondents by checking RAF records of training flights and reports of meteor showers, but usually the MoD responded with a form letter citing phenomena commonly mistaken for UFOs, including aircraft lights and weather balloons.
The files show how UFO reports by the public were taken seriously by the MoD during the Cold War.
A copy of minutes from a Joint Intelligence Committee meeting in May 1959 state that Air Vice-Marshal William MacDonald discussed the issue at the highest level.
He reported that UFOs had been spotted by official and unofficial sources at a rate of one a week. He disclosed that a sample of 16 reports in early 1957 showed that ten had been identified (a meteorological balloon, aircraft navigation lights, aircraft flares, a meteorite, a photographic hoax, faulty radar equipment and "an engineer's amateur experiment") but six were not.
Four of these were radar sightings that remained under investigation. "In each, unusual behaviour of the radar blips in terms of course, speed and heights were reported," he wrote. "Attempts are being made to trace the cause of these sightings to aircraft known to have been near, inexperienced operators or spurious echoes of unexplained origin." The file does not state whether the sightings were ever explained.
Official interest waned when the Cold War ended. Until 1991, when the USSR collapsed, about 200 scrambles took place every year in response to radar sightings that were usually confirmed as Soviet aircraft. After 1991 there were no such scrambles, according to an RAF report compiled in 1996.
David Clarke, a lecturer at Sheffield Hallam University who specialises in UFO reports, said that the MoD steadily lost interest in UFO sightings because they were no longer being supported by radar observations. "The end result of this is them pulling the plug [on the UFO unit] altogether," he said. "Despite all these thousands of sightings they never found anything that was a threat to the nation."
Every time that Britain elected a new prime minister, he added, there would be a sackful of letters asking if he or she would end the alleged UFO cover-up.
The files show that the MoD was painfully aware of being accused of hiding the truth.
In September 1995 a civil servant wrote to the Civil Aviation Authority asking it not to pass on queries about UFOs unless they affected the MoD directly. "A sizeable proportion of the 'UFO' lobby is of the opinion, and is constantly on the lookout for signs, that the MoD may be covering up information relating to the existence of extraterrestrial activities," the civil servant wrote.
"As a consequence of this it is not helpful if the MoD seems to be adopting a 'big brother' attitude in matters which fall outside our bailiwick by appearing to 'insist' that letters of this nature are forwarded to us for reply."
The UFO unit was still able to arbitrate in some strange disputes, however. In July 1999 an irate man wrote to the Government to ask for its help in proving that aliens had landed.
The unnamed man, from Leeds, had made a 100-1 bet with Ladbrokes, the bookmakers, that aliens would land on Earth before December 31, 1999. He was convinced that a wealth of books in Leeds Central Library on the supposed landings at Roswell, New Mexico, in 1947 made him the winner, but Ladbrokes demurred.
The MoD responded: "To date the MoD is not aware of any evidence that might substantiate the existence of alien lifeforms, and therefore supports the view that your bet should not be upheld."
In light of documents released by the National Archives, The United Kingdom's  has investigated claims that  and  may have orchestrated a cover-up of an Unidentified Flying Object sighting by the Royal Air Force.

Numerous public inquiry files suggest that great concern was had for the proposition that former Prime Minister of The UK, Churchill and then US General Eisenhower, knew of an unknown metalic object approaching RAF aircraft off the British coast during World War II. One inquiry noted a discussion between Churchill and Eisenhower overheard by Churchill's body guard by the apparent grandson of the body guard (whose name was blacked out).

The inquiry read, "During the discussion with Mr Churchill, a consultant dismissed any possibility that the object had been a missile, since a missile could not suddenly match its speed with a slower aircraft and then accelerate again ... Another person at the meeting raised the possibility of an unidentified flying object, at which point Mr Churchill declared that the incident should be immediately classified for at least 50 years and its status reviewed by a future prime minister".

Further records showing Churchill's general interest in UFOs were released alongside many other public inquiry files that concluded any UFO sightings were no threat to British airspace and minutes from a Joint Intelligence Committee meeting in 1959, where UFO sightings were a major theme.

Sightings made by officials and civilians were discussed at the Joint Intelegence meeting and 16 cases were singled out, 10 were identified as technical faults, misinterpretations and hoaxes - while 6 remain unidentified.

The unit of the Ministry of Defence that dealt with UFOs was closed last year.