Hi Guys, the importance of part played by the team at Bletchley Park at helping the ones in the front line can never be estabished as to its over all value, but in this text the sinking U864 being a classic example of their input, not only did the admiralty know well in advance of her mission, but knew her plans just as her own crew did. So with a submarine placed ahead of sailing, situated within the planned area of passage, the odds were greatly reduced to locating her, however, the luck comes in to the mix, if it was not for the fact that U864 developed a mechanical fault, forcing her return, then she would probably got a lot farther than she did, if she would have completed her mission is up to speculation as she would have been hunted along the way, most likely betrayed by her own radio traffic, which BdU would not believe had been compromised, but thats another story. The hunting down and sinking of German supply and weather ships previously was also due to the interception and translation of German radio traffic. Regards John