On 5 Dec 1942 the Alcoa Rambler (Master Ernest Henke) left Trinidad in a convoy. She left convoy three days later to proceed independently and steered a zigzag course continuously for four days. At 02.00 hours on 15 December, the vessel was struck by a torpedo from U-174 on the port side at the #3 hold. The explosion destroyed the bulkhead between this hold and the fireroom and the ship developed immediate list to port. One seaman jumped overboard and drowned. Within five minutes the crew of eight officers, 32 men and 15 armed guards (the ship was armed with one 5in and four 20mm guns) began abandoning ship in two lifeboats and four rafts. Then U-174 fired a second torpedo which struck the port side amidships and sent flames 100 feet in the air. The Alcoa Rambler broke in two and sank stern first 200 miles northeast of Natal. On 17 December, one lifeboat with 25 survivors, commanded by the master reached Natal. In this boat was the first assistant engineer who was badly burned. He was taken care of by the armed guard commander who dressed his burns and gave him cigarettes and water. He survived and was later hospitalized at Natal. The second lifeboat with 29 men arrived 11 hours later.

The master Ernest Henke had survived the sinking of his previous ship, the Alcoa Partner, which had been sunk by U-66 (Zapp) on 26 April 1942. His next ship, the Alcoa Prospector was also torpedoed but was only damaged by a torpedo from the Japanese submarine I-27 in the Gulf of Oman on 5 July 1943. The ship was repaired and returned to service.