At 03.58 hours on 13 May 1942 the unescorted Koenjit (Master Rasmus M. Rosenhøj) was hit by one G7e torpedo from U-156 while steaming on a zigzag course about 420 miles east-northeast of Barbados. The ship had been chased for about eight hours and missed with a spread of two torpedoes at 01.20 hours. The torpedo struck on the starboard side aft in the engine room and caused her to sink by the stern. All crew members abandoned ship in two lifeboats, except the master and the chief officer who remained aboard to make sure that everybody had left. They had to jump overboard and swam to the boats when the ship eventually sank. The U-boat surfaced to question the survivors and Hartenstein asked for the name, nationality and destination of the ship. The answers he got from the men were so short and so vague that he was not able to establish the identity. Nevertheless he told them their position and course to the nearest land before leaving the area. The lifeboat in charge of the master with 25 occupants managed to reach the French island La Désirade, but were not allowed to land there as the island served as a leper colony. Fearing internment on the Vichy controlled Guadeloupe, they decided to head for Dominica and reached Roseau on 19 May. The 13 occupants of the other lifeboats were picked up by the US steam tanker Christy Payne and were landed at Newark, New Jersey on 27 May.

The small motor tugboat Letitia Porter carried as deck cargo floated free when the ship sank and was apparently located after drifting for 23 days by U-69 (Gräf) and sunk by gunfire in approx. 18°15N/53°45W.