UNDEFENDED SHORE
On a sunny summer afternoon 75 years ago, Germany’s bloody U-boat campaign along the East Coast of the United States, which had resulted in the destruction of more than 200 Allied merchant ships and the deaths of thousands of civilians, abruptly ended with a rare defeat at the hands of the U.S. Navy.
The last skirmish in the U-boat offensive had begun just after sunset on July 11, 1942, when lookouts perched atop the narrow bridge of U-576 caught the distant silhouette of a group of merchant ships off to the west in the direction of Cape Hatteras, North Carolina. Captain Hans-Dieter Heinicke, the commander of U-576, quietly ordered his 44-man crew to battle stations. Heinicke began to trail the northbound Convoy KN118, bound from Key West, Florida, to Norfolk, Virginia. He ordered his senior radioman to send an encrypted message announcing the sighting to the U-boat force headquarters (Befeblisheber der Unterseeboote, or BdU) in Paris. As the western sky darkened, its operations staff tersely ordered Heinicke “to attack and to report further contact” so that other U-boats could be directed to close in on the formation. Within several hours, U-402, another Type VIIC U-boat, arrived in the area.
Both Heinicke and Kapitänleutnant (Lieutenant Commander) Siegfried Freiherr von Forstner, U-402’s skipper, were experienced and capable U-boat commanders with adequate records of ship sinkings. Heinicke was on his fifth wartime patrol, hoping to add to his record of three ships sunk (totaling 13,387 gross registered tons). Von Forstner’s record was nearly as impressive: In four wartime patrols, he had sunk three ships (totaling 11,135 tons). Both were on their second deployment to American coastal waters since the beginning of the U-boat offensive. But as they hunted the elusive convoy during the next three days, their combat experience would prove to be of no use. Except for a heavily armed convoy passing through every three days or so, the once rich hunting grounds off North Carolina’s Outer Banks were now empty of merchant ships. And the skies were constantly swarming with land-based patrol aircraft.
Two days after Heinicke sighted Convoy KN118, two U.S. Navy patrol aircraft jumped while it was on the surface, straddling it with depth charges that damaged one of its main ballast tanks. Attempts to repair the tanks the next day were unsuccessful, prompting Heinicke to abort his patrol and begin the long return trip to France. ran out of luck the following day, July 14, when a pair of Coast Guard aircraft blasted it with depth charges as it, too, attempted a crash-dive to safety. Forstner reported to BdU headquarters that the attack had caused a battery explosion and other damage, forcing him to abort his patrol as well. Then, on July 15, as was proceeding east into the open Atlantic, Heinicke’s lookouts spotted another formation of merchant ships. This was southbound Convoy KS520 heading from Hampton Roads to Key West. It comprised 19 merchant ships escorted by seven American warships: the old four-stack destroyers and , the 165-foot Coast Guard cutter , the corvette , and three smaller patrol craft. Despite the damage to his boat, Heinicke decided to attack, firing a spread of four torpedoes. One struck and sank the 2,063-ton Nicaraguan freighter ; two others damaged the 8,310-ton American freighter and the 11,147-ton Panamanian- flag tanker . Though successful, the bold attack proved fatal for Heinicke and his men. When compressed- air charges expelled the four torpedoes from the bow tubes, became unstable and popped to the surface in the middle of the convoy. The defenders reacted instantly. A navy gun crew on the American freighter struck the U-boat’s conning tower with at least one 5-inch shell, and two navy OS2U Kingfisher floatplanes swooped in and dropped depth charges that ripped open its hull. sank within seconds, entombing its 45 crewmen on the seabed 721 feet down.
