The KS-520 Convoy Battle was an important event that occurred during the Battle of the Atlantic off the East Coast of the United States. The outcome of this battle turned the tides for Allied Forces on the American coastline. After this battle, German U-boats would never again attack the East Coast with such ferocity.
During the early morning hours of July 14, 1942, 19 merchant ships and five naval escorts in the Key West-bound convoy, KS-520, left Hampton, Va. For the first day and a half, the convoy steamed uneventfully. Captains were drilling their crews and everyone was settling into the routine of a long cruise. However, the ships in convoy KS-520 were unaware that just over the horizon lurked a German U-boat, the U-576. The gray wolf was keeping busy attempting to sink merchant vessels while trying to evade attacks from U.S. aircraft patrols.
Among the escorts for the KS-520 convoy was the Coast Guard cutter, Triton. On the afternoon of July 15th, while about 20 miles off the Ocracoke coast, the Triton detected something thought to be a possible submarine. Two patterns of depth charges were dropped with no result. Then...BAM! Two torpedoes struck an American merchant vessel, the Chilore, and sent a geyser of water over her. Moments later, the J.A. Mowinckel, a Panamanian tanker, was also rocked by a torpedo. In all of the chaos and confusion, the convoy began to break apart. Just then, a fourth torpedo struck the Nicaraguan merchant vessel, Bluefields, which sank below the surface of the Atlantic Ocean only minutes later. In a mere six minutes, U-576 inflicted a heavy toll upon the ships of convoy KS-520.
After the initial attack run, the U-576 popped to the surface only to be fired upon by the remaining convoy vessels, while Allied aircraft dropped depth charges. It was not long before the U-576 sank to her final resting place on the bottom of the Atlantic Ocean.
Severely damaged, the Chilore and J.A. Mowinckel headed towards the North Carolina coast with the USS Spry as an escort. Regrettably, an unfortunate series of events led these surviving members of convoy KS-520 directly towards the Cape Hatteras minefield. Then it happened again; several loud explosions shook the night air. The Chilore and J.A. Mowinckel struck mines, forcing the crews of each vessel to abandon ship. Although the Spry received an escort out of the minefield from patrol vessel, PC-462, and the crews safely reached shore aboard lifeboats, the merchant vessels remained stranded within the Hatteras minefield.
On July 19th, tugboats were sent to recover the abandoned merchant vessels. While trying to salvage the damaged ships, one of the tugs, the Keshena, struck a mine and sank almost instantly. The remaining tug managed to retrieve both the Chilore and J.A. Mowinckel and brought them to Ocracoke for basic repairs. The vessels were then to be sent to Hampton Roads, Va. for salvage, but before the Chilore reached its destination it capsized and sank as it was being towed past Cape Henry off the Virginia Beach coast.
The U-576 inflicted great damage on convoy KS-520 including several dead and wounded sailors as well as the loss of several ships. However, in the end, Allied forces successfully met the threat of the enemy and the attacking u-boat was destroyed. Although the U-576 was not the only u-boat lurking in those waters, this battle changed the course of events off the East Coast. With its convoy techniques and anti-submarine tactics, Allied forces had dashed German hopes of dominating the waters off the East Coast of the United States.