The first time such cooperation happened was in August 1942. The BV had to fix out the floating ice limits and to report if there were possibilities for ennemy ships to pass. The whole action was not well prepared and the BV had very soon mechanical problems and its commander refused to start again. U-255 tried to tow the BV but had a lot of difficulties so that the BV had to be sunk.
Nevertheless this action was considered as hopeful, so it was renewed in August and September 1943