Kretschmer was loath to fire another torpedo to finish the job. His boastful motto was ‘one torpedo, one ship’. Yet dawn approached, and with it the risk of being spotted by an Allied air patrol. Aircraft attack was more feared by U-boatmen than that of an escort vessel, as a well-piloted aircraft could mount an attack on a U-boat before it had a chance to dive to the eighty or so metres required to evade an aircraft-hurled depth charge.
