At 21.56 hours on 3 June 1942 the unescorted M.F. Elliott (Master Harold I. Cook) was torpedoed by U-502 about 150 miles northwest of Trinidad, while proceeding on a zigzag course at 10 knots. The ship had left Newport News in a convoy, left it off the Florida Keys and proceeded for some time together with the C.O. Stillman, which was sunk on 6 June by U-68 (Merten).

One torpedo struck the starboard quarter of the M.F. Elliott well below the waterline. The explosion destroyed the fuel bunker and the fireroom and sprayed fuel oil over the surface of the sea, but did not catch fire. A distress signal was sent to a US Navy PBY aircraft seen earlier in the day. The tanker listed to starboard, settled by the stern and plunged bow up within six minutes. The eight officers, 30 crewmen and seven armed guards (the ship was armed with one 4in, one 3in, two .50cal and two .30cal guns) tried to abandon ship in three lifeboats, but all capsized because the ship sank fast. Four officers and nine crewmen were lost, seven in the explosion and six drowned. The survivors swam to four rafts that had floated free and the PBY remained in contact with them throughout the night. 27 survivors were picked up at dawn the next day by the American destroyer USS Tarbell (DD 142) and later pulled three others from the water before landing them at Port of Spain.
Two men had been picked up by U-502 for questioning. The arriving PBY forced the U-boat to submerge and take the men with them. They were released after three hours and put on a raft with provisions. The two men were picked up five days later by the Brazilian steam tanker Santa Maria and landed at Santos, Brazil on 1 July.