Hi , I have a photo of HMS Tantalus from a propaganda film shot in the Irish Sea circa 1941-43 where she was imitating a German Uboat on fire . My late Father was a seaman and he was volunteered to jump in the sea as if he were a German seaman . I know that she was filmed from an aeroplane as John Woodham ( one of the last survivors from Tantalus still alive ) told me that 4 volunteers were told to go into the sea as they were being filmed and he said that they didn`t get picked up for ages that he remembers quite vividly . There is a photo of this incident in the Captain at the time Hugh Mackenzies book " The Sword of Damocles " . I have searched everywhere but can`t find this propaganda film