In mid-June, the US Coast Guard carried out a special survey to see if a fully-laden tanker sunk by a U-boat off Long Island during the Second World War was leaking oil from her cargo tanks, posing an environmental problem.
In late 1941, the German Naval Staff had realised that Allied ships were vulnerable in the western Atlantic, particularly off the east coast of the United States. The head of the U-boat Command, Admiral Karl Donitz, had long advocated that the main role of the German Navy was to sink enemy ships but he had been unable to convince the German leader Adolf Hitler that the best way to achieve this was by U-boats.
The entry of the United States into the war following the Japanese attack on Pearl Harbor on Dec 7 resulted in Hitler finally agreeing to Adm Donitz’s request to allow the U-boats to operate off the US east coast. This decision was made on Dec 12, the day after Germany declared war on the United States. The operation was given the name Paukenschlag, and is referred to as Operation Roll on the Drums or Operation Drumbeat.
Hitler eventually ordered the US Atlantic coast and the waters of the Caribbean to be blockaded, so allowing U-boats to be justified in sinking ships of neutral countries trading with the United States. There was just one exception, the ships of Spain which were vital in providing a link between Germany and the east coast of South America, particularly Argentina.
Some five weeks after Germany declared war on the United States, Operation Paukenschlag got underway when five U-boats were sent to operate between the Gulf of St Lawrence and Cape Hatteras. The U-boats, which all sailed from the captured French Biscay port of Lorient, were: U-66 which left on Dec 15; U-109 on Dec 27; U-123 on Dec 23; U-125 on Dec 18; and U-130 which left Lorient on Dec 27.
It was clear that all five U-boats would have to return home starting at the end of January due to the fact that they could not easily be resupplied with fuel, supplies and torpedoes.
Atlantic convoys still started and ended at Halifax so the first U-boats operated off the Canadian coast south of Nova Scotia. Over 40 merchant ships were lost in this area in January and February.
On Jan 11, the U-123 sank the Blue Funnel Line ‘football ship’ Cyclops, 9,076grt, south-east of Cape Sable, Nova Scotia. Eighty-eight of the cargo liner’s crew died, mostly of exposure before they could be picked up, and 89 survivors were rescued by the Royal Canadian Navy minesweeper Red Deer. The cargo liner was bound from Australia to Britain.
The U-123 then sailed to operate off the US coast and on Jan 14, she sank the Norwegian tanker Norness, 9,577grt, of the Tanker Corporation, and sailing under the Panamanian flag. The Norness was on her way from New York to join a convoy at Halifax, Nova Scotia, and carried a full cargo of 12,000 tons of fuel oil for Liverpool. The Norness was torpedoed near Long Island and sank with the loss of one of her crew.
Among the British tankers that had loaded oil in the United States was the Coimbra (pictured left), 6,768grt, of the Socony-Vacuum Transportation Co, of Montreal and registered in London. The tanker also sailed from New York for Halifax to join a convoy and her cargo of some 9,000 tons of lubricating oil was to be discharged at a port on the west coast of Britain. She had a crew of 40 and carried six gunners.
On Jan 15, south-east of Rhode Island, the U-123 intercepted the Coimbra and shortly before 0900 fired one torpedo which hit her on the starboard side at the aft end of the bridge structure. The huge explosion started a fierce fire which quickly spread and the tanker took a list to starboard as water flooded in to the hole. Less than an hour later, the U-boat fired another torpedo which hit the burning tanker in the engine room and another explosion started more fires. The burning tanker could clearly be seen from the shore before she sank by the stern.