 Most importantly he persuaded the early waves to stop bombing a misplaced TI on the Polish slave labour camp at Trassenheide to the south, though not before 500 slave workers were killed in just a few minutes.5 Group attacked last, and Cochrane's crews were authorised to use time-and-distance if the Pathfinder markers were obscured or off-target.In their first range practice for this attack, 5 Group had averaged a 1,000-yard error using time-and-distance.