The post-war diaries of Guy Liddell, then-deputy director general of MI5, show the Joint Intelligence Committee heard a presentation from Captain James Caiger, the army's pigeon expert who ran the Army's pigeon loft after the war.
Caiger informed the British spy-masters that the homing instinct of the birds could be used to trick them into following a radio beam, The Independent newspaper reported today.
In an entry for October 3, 1946, Liddell described how Caiger came to see him. "He is our pigeon expert. He is, in fact, the nearest thing to a pigeon that I have ever seen. He talks, thinks and dreams about them," he wrote.
"He has had pigeons since he was a boy and his father had pigeons before him. I asked him about the homing instinct. He said that the matter is quite unsolved. There is however, one curious fact, namely that in a sun spot year all pigeons go hay-wire."
"Sun spots are, of course, minute radio active particles thought how they affect the pigeons' homing instinct nobody knows. This gives some colour to the suggestion that pigeons might be able to home on an electric beam, in other words that you might have radio-controlled pigeons."
MI5 files previously released refer to plans to train pigeons to carry explosives and fly into enemy searchlights.
It was not until 2007, however, that scientists were able to perfect plans similiar to those mooted by Liddell.
The diaries have been released to the National Archives in Kew.
