Paul Kemp, U-Boats Destroyed (1997) , p164 Axel Niestle, U-Boat Losses during World War II (1998) , p59 However, an attack by the British destroyer HMS Wanderer D74 6 and frigate HMS Glenarm K258 6 at coord, on 17 January took place two days and about 220 nautical miles from  U-377's last known position (where she would have been, had she been on course and sailing at the most economical speed, as ordered) and recent research suggests that this was the U-boat's fate.