The eleven other VIIs of the April group headed for the United States East Coast and the Bahama Islands. Inbound, two of the skippers, Hans-Heinrich Giessler in U-455 and Gerd Kelbling in the new U-593, were held in Canadian waters to hunt for the big troopship convoy AT 15-NA 8. Their hunts for this military target were futile, but the diversion took Giessler’s U-455 into the path of the lone 7,000-ton tanker British Workman, which he sank by torpedo on May 3 about 200 miles south of Cape Race.
Both boats had expended considerable fuel during the hunt for AT 15-NA 8 and they were unable to reach Cape Hatteras. Both remained in the waters between Nova Scotia and northern New Jersey and New York. Giessler in U-455 had no further luck in American waters, but homebound in the mid-Atlantic he sank a second British tanker, the 6,900-ton George H. Jones. Kelbling in U-593 hit the Greek freighter Stavros for damage and sank the 8,400-ton Panamanian tanker Persephone close off the coast of northern New Jersey. She was the only tanker sunk in the Eastern Sea Frontier in the month of May. Neither Giessler nor Kelbling refueled this time. The former was out sixty-two days, the latter fifty-nine days.
Nine VIIs patrolled the waters from New Jersey southward. As expected, these boats confronted greatly intensified ASW measures, including “heavy” air patrols all along the East Coast, mounted by 172 Navy and Coast Guard aircraft, plus the Army Air Forces planes. By the time these boats arrived, the Bucket Brigade convoys were in full operation and, as related, on May 14, the first Key West-Norfolk-Key West convoys sailed. Sixteen destroyers of the Atlantic Fleet† spent an aggregate 238 days under control of the Eastern Sea Frontier: 184 days at sea on ASW missions, 54 days in replenishment or refit.
The historian of the Eastern Sea Frontier wrote of the month of May, in part:
There was an extraordinary change this month in the fortunes of the war beneath the sea. April, when ships had gone down at the rate of almost one per day, was the worst month within the Frontier since the submarine first invaded this coast. As it drew to a close there was no indication and no hope that these severe losses could be appreciably reduced in the foreseeable future. In fact when two vessels went down on the 30th [of April], it was possible to predict that sinkings might well increase. Then, in the first 17 days of May not one ship was lost in the Eastern Sea Frontier.* In the fourteen days that remained [of May] only four vessels were sunk in our waters….†
While inbound to the Cape Hatteras area, three VIIs sank ships near the outer boundary line of the Eastern Sea Frontier:
• Ulrich Gräf, the new and aggressive skipper of the U-69, got the 600-ton four-masted American sailing vessel James E. Newsom by gun.
• Friedrich-Hermann Praetorius in U-135 got the 7,100-ton British freighter Qu’Appelle. Responding to her SOS, a Canadian aircraft sighted her lifeboats and, two days later, a Canadian minesweeper rescued thirty-four survivors from the boats. They reported thirteen crew had been killed in the sinking.
• Gerhard Feiler in U-653 got the 6,200-ton British freighter Peisander, en route from Australia. A week after the sinking, her five lifeboats reached Nantucket Island.
One VII that reached the Cape Hatteras-Cape Lookout area was lost: the U-352, commanded by thirty-one-year-old Hellmut Rathke. He had made one prior patrol in the defense of Norway during which he fired at a “destroyer” but he had not yet hit anything. After he replenished inbound from U-459, Rathke boldly closed on Onslow Bay, North Carolina, on May 8. There he found a freighter escorted by a Coast Guard cutter. He fired three torpedoes at the two ships, but all missed or malfunctioned.
Late in the afternoon on the following day, Rathke sighted another Coast Guard cutter sailing alone, thirty miles south of Cape Lookout. She was the 165-footer Icarus, southbound from New York to Key West to join the new coastal-convoy organization. Commanded by fifty-two-year-old Maurice D. Jester, who rose from the enlisted ranks, Icarus was a taut ship with five months of ASW duty. Believing the Cape Hatteras-Cape Lookout area to be infested with U-boats, Icarus was on full alert. As Rathke closed to point-blank range to fire a single torpedo, Icarus got a solid sonar contact at 2,000 yards. Rathke shot before Icarus take action, but the torpedo prematured, or malfunctioned, or hit the ocean bottom, erupting in an explosion that shook Icarus from stem to stern.
Jester and the crew of Icarus reacted smartly and professionally, firing five shallow-set depth charges from the tracks and Y gun at a likely spot. All five closely straddled U-352 and exploded with immense force, wrecking the boat and killing the first watch officer, Josef Ernst. Rathke bottomed at 114 feet to play dead, but when Icarus dropped five more close, shattering depth charges, he surfaced to abandon ship and scuttle.
When U-352 broached stern up, Icarus raked her with her 3” bow gun and machine guns from close range. This hail of fire killed or wounded many Germans who were leaping into or already in the sea. Homer Hickam wrote that an Icarus crewman yelled at his fellow Americans: “For God’s sake! Don’t shoot them in the water!” Struggling in the sea, shouting to the Americans to stop shooting and to save his wounded men, Rathke used his belt as a tourniquet on a wounded machinist, Gerhard Reussel, whose left leg had been shot off.
Fearing that another U-boat might be nearby, Jester hauled Icarus away, requesting instructions from various naval shore commands by radio. Should he rescue the German survivors or leave them in the water? Directed to rescue the survivors, Jester returned to the scene within the hour and fished out thirty-three Germans, including machinist Reussel, who died of his wounds on board Icarus, and took them into Charleston, South Carolina. The bodies of thirteen other Germans who were killed inside the boat or in the water were left behind. The thirty-two survivors—the first German submariners to be captured by the Americans—were taken to an internment camp at Fort Bragg, North Carolina. Reussel was buried with military honors in the National Cemetery at Beaufort, South Carolina.
The Navy ordered salvage divers to comb U-352 to obtain Enigma and other intelligence information, but since Icarus had failed to buoy the wreck, the task was difficult. Divers from the Navy salvage tug Umpqua, protected from U-boat attack by the British ASW trawlers Northern Duke, Northern Dawn, and Stella Polaris, finally found U-352 in 114 feet of water on May 23. They buoyed the wreck, reported on the damage, and took photographs, but for various reasons, salvage operations were not pursued. No divers entered the boat. She yielded no intelligence information.*
Three of this group of VIIs attacked ships on the homeward voyage. On June 1, Dietrich Borchert in U-566 sank the 9,000-ton British freighter Westmoreland, only his second success in two patrols to American waters. Upon reaching France, he left the boat for other duty. When Bermuda learned of Westmoreland’s loss, the old (1918) 1,000-ton American minesweeper Gannet, serving as a tender for the Navy’s Catalina Squadron 74 on Bermuda, and a British ASW yacht, Sumar, put out to look for survivors. Gerhard Feiler in U-653 came upon Gannet and Sumar on June 7. He torpedoed Gannet, which sank in four minutes.* Praetorius in U-135 sank the 4,500-ton Norwegian freighter Pleasantville well east of South Carolina.
In view of the poor hunting and the strong ASW measures in the Eastern Sea Frontier, Dönitz directed five VIIs of the April group, which had replenished from U-459, to patrol far to southward: four to the Caribbean Sea, one to the Gulf of Mexico.
The first of the four VIIs to reach the Caribbean Sea was Dietrich Hoffmann in the new U-594. His patrol was a disastrous flop: eight misses on a tanker and a freighter, and a gunner washed overboard and lost during a gun attack on the tanker. Upon receiving Hoffmann’s reports, Dönitz canceled a proposed second refueling and ordered him to return directly to France at once. He arrived on June 25, completing a seventy-six-day patrol during which he sank nothing. After a careful review of the patrol, Dönitz sent Hoffmann to other duty and gave command of U-594 to another officer.
The other three VIIs followed. Patrolling near Trinidad, Ulrich Gräf, the new skipper of U-69, sank two ships for 9,400 tons, including the 6,800-ton Norwegian tanker Lise, but he was then ordered to carry out a special mission off the Vichy island of Martinique (see below). Ritterkreuz holder Günther Krech added luster to his and U-558’s reputation by positively sinking five more ships, bringing his total for the patrol to six confirmed ships for 16,400 tons, plus damage to the 7,100-ton American tanker William Boyce Thompson. Ritterkreuz holder Gerhard Bigalk in 7-757 sank two medium American freighters (Nicaro, Isabella) for 4,555 tons. Homebound, he fired three torpedoes at a big freighter, but two failed and the third missed.
The aggregate returns of the sixteen VIIs that sailed to the Americas in April declined: thirty-three confirmed ships (seven tankers) sunk plus five sailing vessels and fishing trawlers for about 158,200 tons.
As related, the most successful patrol was that of Ritterkreuz holder Reinhard Suhren in U-564, completed just before the Allies initiated full-scale convoying on the United States East Coast. Including the “neutral” tanker which brought Mexico into the war, Suhren sank four confirmed ships (two tankers) for 24,400 tons and damaged two other ships for 13,200 tons. The second best patrol was that of Karl Thurmann in U-553, who, as related, penetrated the Gulf of St. Lawrence on his own initiative and sank there and elsewhere three confirmed ships for 17,000 tons. Three other boats (U-455, U-588, and U-753) sank about 14,000 tons each, including three tankers.† Two (U-69, U-735) sank about 12,000 tons each, including one tanker. Six boats sank under 10,000 tons each, including one tanker, and three boats (U-213, U-352, and U-594) sank no ships at all. One boat, U-352, was lost.
Eleven of these sixteen VIIs refueled. Discounting the lost U-352, the other ten were able to extend their patrols to an average sixty-nine days and sank an average 2.7 ships per boat per patrol. The five VIIs that did not refuel, including the luckless U-213(minelayer), patrolled for an average sixty days and sank an average 2.0 ships per boat per patrol. Discounting the badly handled U-213, the four VIIs that did not refuel sank an average 2.5 ships per boat per patrol. Thus it was that the refueling of this group extended the patrols by about nine days, but did not appreciably increase the sinkings. Much still depended on the area of the patrols, aggressiveness of the skippers, skill of the crews, weather, luck, and other factors.
Contrary to the myths that arose in later years, the returns of the five VIIs sent to the Caribbean and Gulf of Mexico were disappointing. At sea an average of seventy days, these boats sank eleven ships for about 38,600 tons in the Caribbean and gulf, an average of 2.2 ships for 7,700 tons sunk per boat per patrol. This return was no better than the VII returns from other waters and it was small compensation for the extreme hardships the crews endured from the terrible tropical heat and humidity and the chronic shortages of food and fresh water.
In the first five months of the campaign in the Americas, Dönitz mounted seventy patrols by Type VIIs. These sank 155 confirmed ships for 778,307 tons, including all trawlers and sailing vessels and ships encountered in the ocean coming and going. Partly reflecting the result of the attacks on convoy Outbound North 67, the nine VIIs that sailed in February achieved the best results.
For those staffers who opposed sending VIIs to the Americas, the decline in returns of the April boats was persuasive. The fifteen surviving VIIs that sailed in April had spent 991 days at sea to sink 158,210 tons of confirmed shipping, merely 25 percent of what was thought to be a reasonable return. The critics made the case for operating the VIIs in packs closer to home, especially in summertime, when the climate in southern American waters was so hot and debilitating, and so much more favorable for operations in the North Atlantic.
Dönitz conceded that the return on investment for the VIIs in American waters was marginal and that the patrols were very hard on the crews. And yet he did not want to stop altogether the VII patrols to American waters. Even a few VIIs operating on the Eastern Seaboard would insure that the Allies continued convoying there with the usual shipping delays and would tie down substantial numbers of ships and aircraft on ASW missions. However, he directed that most of the VIIs sent to United States waters in the month of May should first carry out special missions, such as minelaying or landing Abwehr agents.