I was leading a formation of 4 Chinooks on a navex in Germany, and we had booked ourselves into Coleman US Army Airfield (Mannheim) for a refuel. Good old Strike Command issued fresh random formation callsigns every few weeks and, on that day, we were 'Corncrake'.
As we approached Coleman, my NH called the formation across to their Tower frequency, and the following exchange took place:
Chins - 'Coleman, this is Corncrake Formation'.
Tower - 'Errr, is that Corncrisp information?' [giggling amongst crew]
Chins - 'Negative, Corncrake Formation.'
Tower - 'Err, understand Cornflake Information?' [guffawing amongst crew]
Chins - 'Never mind, 4 RAF CH47s, 5 miles to the South, to join'.
Tower - 'Ah Roger RAF CH47s, you are clear to join.'
The controller was clearly not an ornithologist.