The story about pigeons in WWII bombers was a classic piece of disinformation, just like the one about carrots improving night vision. Both stories camouflaged much more interesting and secret stories. The carrot one is now well known to have been a deception to mask the use of radar in night fighters and its success in finding targets to shoot down.
The pigeon story is less well-known. My uncle Robert, later to become well-known for writing off a prototype Windsor, told me the tale in the home where his life ended, just before that sad event. Early in 1943 there was great concern that bombers were returning after a night raid, getting lost and landing on a strange airfield if they were lucky, or crashing if not. Some bright spark thought that if pigeons could be trained to fly in front of the bomber, attached with a length of string, their natural homing instinct would mean that they flew in the direction of home, and all the pilot had to do was follow.
This worked quite well, apart from the fatal flaw that the little fellows were getting exhausted very quickly by the effort needed to keep ahead of the bomber. The boffins at Farnborough worked on this, and came up with the idea that if the pigeon was kept on the coaming behind the windshield, it could be trained to indicate the heading for home by positioning itself appropriately, left, right or centre. This proved to be a solution, and uncle Robert flew a few missions to Germany to test the system on the return journey. The tiny heroes passed the test with flying colours, and a top secret programme was launched to acquire and train several squadrons of pigeons for this work. Unfortunately, it was realised, after months of trying unsuccessfully to locate and train the avian recruits, that nearly every pigeon in Great Britain had either been acquired by SOE for communications, as well as the Army, or eaten by the population at large, by that time very hungry due to rationing, and the programme came to nothing.
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