At 04.16 hours on 26 May 1942 the unescorted and unarmed Alcoa Carrier (Master Victor L. Parsons) was hit by a torpedo from U-103 while the steamer had discontinued her zigzagging course due to cloudy weather. The torpedo struck the #2 hatch on the starboard side at a depth of about twenty feet below the waterline. The compartment was flooded, the engines were stopped and the radio was destroyed. After 25 minutes the U-boat surfaced and fired about 23 rounds at the vessel from a distance of 400 yards. 17 shells hit the area of the bridge and started a fire. The crew of eight officers and 27 men abandoned ship in two lifeboats.

Winter asked the master about the name and the speed of the vessel and if all the crew were accounted for. He then gave a package of cigarettes to the crew. At 05.15 hours, U-103 fired a second torpedo which hit amidships and left after one hour when the Alcoa Carrier sank bow first about 125 miles west-northwest of Montego Bay, Jamaica. On 30 May, a Cuban gunboat picked up 33 men and took them to Havana, Cuba. An aircraft of the US Navy rescued the remaining two men and took them to Key West.