United States Navy in the Battle of the Atlantic. This mission proved to be only the beginning of American escort operations prior to the formal entry of the United States into World War II, as ships of the Support Force escorted 14 convoys between 16 September and 30 October. As the months wore on, clashes of American warships with German submarines grew in frequency and intensity. was damaged by a German torpedo on 17 October, and suffered a similar fate on the 30th. The next day, was sunk by the . Over the ensuing period from 1 November to 7 December 1941, Support Force destroyers conducted seven round-trip convoy missions in shepherding 14 convoys consisting of some 550 ships across the North Atlantic. World War II In the period following full-scale American entry into the war with the Japanese attack on Pearl Harbor on 7 December 1941 and until the middle of February 1942, Support Force destroyers escorted a dozen convoys in each direction across the Atlantic—750 ships—in comparative safety. On the night of 4 February 1942, Upshur departed Londonderry Port, Northern Ireland, in company with , , , and the United States Coast Guard cutter . Throughout the day on 5 February, the ships hunted a U-boat whose intentions seemed to be to follow the Americans to their outbound convoy assignment. Seven times the destroyers and the Coast Guard cutter attacked the submarine, dropping 30 depth charges, but could not "kill" the elusive submersible. After rendezvousing with Convoy ON 63 on the morning of 7 February, the escorts shaped a course southwest with the 30 merchant vessels, shepherding them along in the wintry seas. Upshurs lookouts spotted a U-boat running on the surface two miles (3 km) away and gave chase, but the German lookouts were alert, and the submarine submerged before Upshur could attack. For two hours, Upshur and Ingham scoured the area, dropping 15 depth charges before they returned to their stations. Upshur had no sooner returned to station when she again spotted the U-boat away. Accelerating to flank speed, the flush-decker headed towards the enemy, only to have the U-boat submerge out of sight once more. Upshur fired two rounds from her forward gun—both shells splashing around the enemy's disappearing conning tower. Gleaves soon arrived on the scene and assisted Upshur in searching for the U-boat. Neither ship was able to make contact with the enemy