The City of Flint (Master John B. MacKenzie) sailed from New York as part of convoy UGS-4. While en route she encountered a storm that caused her deckload to shift and she straggled from convoy. The ship maintained a zigzag course at 11 knots and tried to find the other ships, when she was hit by one torpedo from U-575 at 22.05 hours on 25 January 1943. The torpedo struck on port side at the #1 hold and ignited the oil and gasoline stored there. As the vessel settled by the head, flames engulfed the forward section. With the engines secured, the crew of ten officers, 30 crewmen, 24 armed guards (the ship was armed with one 4in, one 3in and six 20mm guns) and one US Army Security officer abandoned ship with four lifeboats in rough seas within ten minutes. Then a second torpedo struck the port side aft of the bridge and the ship sank bow first at 23.05 hours about 300 miles south of Flores, Azores. Two crewmen and three armed guards were lost in the sinking. The chief cook Robert Daigle was picked up by U-575 as prisoner and was later taken to the POW camp Marlag und Milag Nord. Three of the boats stayed in the area for two days before setting sail for the Azores. They used a portable radio for sending distress calls. The following day, the Portuguese destroyer Lima (D 333) picked up 48 men and landed them at Ponta Delgada, Azores. The destroyer had also tried to locate the missing fourth lifeboat, but became involved in another rescue operation when they came across the survivors from Julia Ward Howe, which had been sunk by U-442 (Hesse) on 27 January 1943. The remaining lifeboat from City of Flint with eleven occupants was not located and one crew member died before its red sail was eventually spotted by HMS Quadrant (G 11) (LtCdr W.H. Farrington, RN) in position 11°50N/18°04W south-southwest of Dakar on 12 March 1942. The ten survivors were rescued and taken to Gibraltar and found to be very weak, but in otherwise good condition after a open boat journey of more than 1600 miles in 46 days.