Derna, Libya
On the morning of 17 June the convoy was northwest of the port of Derna, Libya. At 0733 hours many of the men were below decks having breakfast when commanded by Oberleutnant zur See Johann-Otto Krieg fired two torpedoes. Accounts differ as to what followed. U-boat historian Guðmundur Helgason states that one torpedo hit "Yoma", but Second World War blogger Martin Cherrett states that both of them hit her, one in her engine room and the other in her number 4 hold, sinking her within five minutes. Either way, the Chief Officer, A Olding, reported that she sank rapidly. Olding stated that the explosion destroyed the after engine room bulkhead, rapidly flooding the engine room, boiler room and no. 5 hold and blowing the hatches of nos. 3 and 4 holds. As men scrambled for safety, the ladders on No. 2 mess deck collapsed, trapping many men below decks.