From the German viewpoint, the U-boat war in the North Atlantic in the last two weeks of March went from bad to worse. Setting off on his second patrol from Lorient in U-69, Jost Metzler wrote that the weather was “appalling,” even worse than it was on his first patrol in February. The “elements seemed to have gone mad,” he remembered. It was impossible to conduct organized reconnaissance; visibility was virtually nil.
Nonetheless the Condors, based in Norway and France, flew patrols. On March 19, they reported three convoys, two outbound and one inbound. With merely five boats in the north hunting grounds, all engulfed in raging seas, Dönitz was unable to do much about the reports. He ordered Engelbert Endrass, fresh from Lorient in U-46, and three other boats, including the new VIICs U-98 and U-551 from Germany, to intercept one outbound convoy, but none of the four boats could find it.
A day later, March 21, Metzler in U-69 came upon a convoy inbound from Halifax. Dönitz directed Herbert Schultze in U-48 and four Italian boats in the area to converge on Metzler’s report. But during that day Metzler, tracking submerged, was detected and driven deep by two aggressive escorts. Working as a team, the two escorts depth-charged U-69 for “several hours,” throwing the boat “backwards and forwards,” Metzler wrote melodramatically, in “a slow, bitter, life-and-death struggle….” During the struggle, the convoy got away. The destroyers finally broke off the attack to rejoin the convoy, leaving Metzler and his crew thoroughly shaken.
Fritz-Julius Lemp in the new U-110, patrolling far to the west of Iceland on the night of March 23, found a 2,500-ton Norwegian freighter. He tracked her carefully and fired a torpedo at close range. It missed, as did two others, fired singly. These three misses raised Lemp’s total misses on this patrol to nine, doubtless reflecting the lack of practice in the Baltic because of the ice conditions. Lemp, however, blamed not himself or his fire-control team, but the torpedoes.
Having “lost confidence” in the torpedoes, Lemp, “fighting mad,” attacked the ship with his 4.1” deck gun. In the excitement of this first gun attack, “somebody” (as Lemp put it) forgot to remove the tampion (waterproof plug) from the muzzle of the gun barrel. When the crew fired the first shell, the gun “was blown to bits.” No men were killed or seriously hurt, but the hurtling pieces of steel slashed through ballast-tank vents and fuel tanks, causing severe damage and heavy oil leaks which forced Lemp to abort, having sunk no ships that were confirmed in postwar records. He arrived in Lorient in an angry mood, complaining of the lack of training in the Baltic and the unreliability of the torpedoes.
The increasing number of reported torpedo failures caused grave concern at Kerneval and prompted yet another close analysis. The study revealed that six new boats sailing from Germany had experienced twenty-one torpedo failures or misses in the month of February. In spite of the restricted shooting practice in home waters and the unfavorable seas, these failures were not the fault of the skippers, Dönitz insisted, but had to be some new “unexplained” defect in the torpedoes. One possible explanation, Dönitz speculated, was that the unprecedented extreme cold in Germany was adversely affecting the inner mechanism of the torpedoes. Hence he insisted that boats sailing from Germany not be loaded with torpedoes that had been exposed to extreme cold, and furthermore, that tests of torpedo performance in extreme cold be carried out.
Farther east that same day, the new VIIC U-551, commanded by Karl Schrott, age thirty, from the duck U-7, reached her patrol area southeast of Iceland. Commissioned on November 7, the U-551 had completed her final workup in the ice-free waters off Bergen, sailing on March 18. On this fifth day of his maiden patrol, Schrott found the lone 7,430-ton Belgian freighter Ville de Liège, and prepared to attack at dawn on the surface. Spotting U-551, Ville de Liège radioed an alarm.
The British armed trawler Visenda, which was escorting a nearby convoy, responded. Racing up at full speed (13 knots), Visenda saw U-551 on the surface four miles ahead. The U-boat crash-dived, but Visenda closed and got sonar contact, held it, and during the next hour and a half, fired a total of eighteen depth charges. These charges destroyed U-551. Visenda—the first ASW trawler to kill a U-boat—brought back proof: a plywood locker door with German lettering, articles of clothing stenciled with six different German names, a novel in German, and “pieces” of a human body, identified by medical authorities as the heart and lung of “an adult but not an old person.” German POWs identified the locker door; it came from the port side aft of the bow compartment. Based on this—and other data—the Admiralty’s Assessment Committee speculated that one of Visenda’s depth charges must have detonated a torpedo in U-551’s bow compartment, demolishing the forward end of the boat and blowing the locker, clothing, and other debris to the surface.
When U-551 failed to respond to radio queries that night, Dönitz was gravely concerned. If, as he feared, U-551 had met with misfortune, it meant that five U-boats—about 25 percent of the Atlantic operational force—had been lost in the area south southeast of Iceland in a period of merely seventeen days: U-47 (Prien), U-70 (Matz), U-99 (Kretschmer), U-100 (Schepke), U-551 (Schrott). Besides that, U-37 (Clausen) had been rammed submerged and had survived only by greatest good luck, and U-A (Eckermann) had nearly been lost in a depth-charge attack.
The loss and near loss of seven boats in so brief a period in the North Atlantic gave rise to the suspicion that the British had developed some ndw means of locating U-boats. But Dönitz had no idea what it might be. Was there a spy in the Kriegsmarine or Luftwaffe with access to U-boat positions or radio traffic? Had British scientists achieved some technological breakthrough in radar that enabled them to put sets on escorts? Had British scientists developed a new and tremendously improved sonar? Or DFing gear? Or some wholly new device unknown to German science?
These suspicions prompted Dönitz to withdraw the boats from the Northwest Approaches. On March 25, he repositioned the six boats left in the hunting grounds on a 300-mile north-south line at 20 degrees west longitude. The extreme northern end of the line—closest to Iceland—was occupied by the most experienced skipper and boat: Herbert Schultze in the record-holding U-48. Engelbert Endrass, in U-47, occupied a position in the center of the line.
Schultze in U-48 found an inbound convoy passing south of Iceland on March 29. This was Halifax 115, guarded by eight escorts. With remarkable daring, skill, and calm, Schultze attacked and fired five torpedoes which sank four ships. He claimed 24,500 tons; his confirmed score was four ships for 17,300 tons, plus one tanker damaged. In view of the heavy escort, Dönitz ruled against sending the “extremely inexperienced boats” to help Schultze. No other boats found the convoy.
That same day, farther south in the patrol line, Metzler in U-69 found convoy Outbound 302. In response to his alarm, Schultze in U-48 and Endrass in U-47 attempted to intercept. Endrass found it, but was only able to sink a 1,800-ton freighter. Still tracking far to the west on March 30, Metzler sank what he claimed to be a 7,000-ton freighter, but which in reality was half that size. In this, and a previous action, Metzler reported five electric-torpedo failures, which combined with the nine misses or failures reported by Topp in U-552 and a similar number by Lemp in U-110, intensified the concern at Kerneval about torpedo reliability.
Altogether in March 1941, three hundred loaded ships crossed the North Atlantic, all from Halifax.* Bedeviled by an acute shortage of U-boats, by foul weather, by increasingly aggressive surface and air convoy-escort forces (some with 1.5 meter-wavelength radar), and by the failures of the Condors and Italian submarines, the Germans in that area turned in poor results: a total of twenty-four confirmed ships sunk, half of them loaded ships (four tankers) in eastbound Halifax convoys. Almost half of these had been sunk by two Ritterkreuz holders: Kretschmer in U-99 and Schultze in U-48. In return, British forces had sunk five U-boats, an “exchange rate” of about five British ships for each U-boat lost, a disastrous ratio for the U-boat arm.
In striking contrast to the boats in the north, the three Type IXBs enjoying better weather in the south continued to do very well. Off Freetown, on March 16, Jürgen Oesten in U-106 made contact with another convoy, Sierra Leone 68, en route to Britain. Oesten radioed an alarm and beacon signals to bring up Georg Schewe in U-105, then attacked, sinking a 6,800-ton freighter. Mounting a second attack on the next night, Oesten claimed sinking three freighters for 21,000 tons and damage to another. Schewe in U-105made contact, and over the next three days, March 18 to March 21, the two boats chewed away at the convoy, until all fourteen internal torpedoes on each boat had been expended. Schewe sank four ships for 25,500 tons; Oesten in U-106 claimed one “freighter” sunk, one damaged. Unknown to Oesten, the “freighter” claimed as sunk was actually the battleship Malaya, which was escorting the convoy. Slightly damaged, Malaya limped across the Atlantic to the island of Trinidad, thence to the United States, where, as related, under the provisions of Lend-Lease, she was repaired and refitted along with the battleship Resolution, which had been badly damaged by the Vichy French submarine Beveziers in the abortive Allied attack on Dakar.
Schewe and Oesten reported great success. In seven days of tenacious attacks, Schewe claimed sinking six ships for 41,000 tons, Oesten five ships for 36,000 tons—a total of eleven ships for 77,000 tons. The confirmed score was less: Schewe five ships for 27,000 tons, Oesten three ships for 17,000 tons—a total of eight ships for 44,000 tons, plus Oesten’s hit on Malaya, which put her out of action for months.
Winston Churchill was especially shocked and enraged by the losses in this convoy. In a “rocket” to First Sea Lord Dudley Pound he expressed his displeasure and criticized the absence of destroyers in the escort, especially since Malaya was in the formation. Pound replied that the destroyers at hand did not have sufficient range to sail with Sierra Leone convoys, and refueling at sea was deemed to be too dangerous since the ships involved were virtually unmaneuverable during the process. To this Churchill responded: “Nonsense!” If there were four destroyers present, three could protect the other one while it refueled from a tanker in the convoy.
The third IXB in southern waters, Georg-Wilhelm Schulz’s U-124, attempted to rejoin the others after resupplying from Kormoran, but she had a catastrophic failure in both engines, which left her helpless. After the engines were repaired, she closed the coast of Africa and sank a lone 3,800-ton British freighter, bringing Schulz’s total credited sinkings, including substantial overclaims, to 100,117 tons, earning him a Ritterkreuz. While Schulz was closing on Freetown, Schewe in U-105 and Oesten in U-106 downloaded deck torpedoes and then hauled westward and resupplied from Kormoran and the supply ship Nordmark, respectively. En route to the rendezvous, Oesten claimed sinking a 5,000-ton freighter, bringing his total claims to about 82,000 tons. Having heard from B-dienst that Oesten had hit Malaya, Dönitz awarded him a Ritterkreuz*
To then Dönitz, unshakably convinced that the decisive naval battleground lay along the convoy routes in the Northwest Approaches—between Iceland and the British Isles—had resisted to the utmost any “diversion” of U-boats from that area. But the poor returns and the loss of five boats to “obscure” (i.e., unexplained) causes (three of them commanded by his most experienced and notable skippers) led him to a profound decision: He would withdraw all U-boats from that rich target area for the time being and disperse them to more distant areas where British ASW was less intense, such as the waters west of Iceland and in the South Atlantic.
This little-noted decision was a milestone in the U-boat war against the British Empire: the first clear-cut defeat for the German submarines.
The principal reason for that defeat was the paucity of U-boats. Counting all gains and losses, at the end of March 1941, Dönitz still controlled only twenty-seven combat-ready oceangoing boats, the number with which he began the war nineteen months earlier. Three of these boats were temporarily unavailable because of battle or other damage; three were patrolling off West Africa. That left only twenty-one boats to patrol the North Atlantic convoy routes, and half of these were new. Owing to the travel and refit time, only a third—seven boats—could be in the hunting grounds at one time. In view of the clever diversion of convoys and the ever-growing numbers of experienced, aggressive-minded surface escorts, there were simply not enough U-boats to find, track, and carry out successful pack attacks on enemy convoys in the Northwest Approaches.
The decision to disperse the U-boats to distant waters west of Iceland and to the South Atlantic entailed a severe penalty. The Type VIIBs and VIICs in the North Atlantic did not have sufficient fuel capacity for extended patrolling at long ranges, especially if required to chase one or more convoys at high speed. The fuel limitations were to reduce the number of boats available to form a pack in the more westerly North Atlantic hunting grounds. Similarly, the extreme distances involved in South Atlantic patrolling were to reduce the combat availability of the bigger boats sent to that area. Notwithstanding the prospective increase in the size of the Atlantic U-boat force, the number of boats that could be brought to bear on enemy shipping on any given day was to decline.
It was at this time—March 1941—that Lend-Lease was enacted and that President Roosevelt transferred the ten Coast Guard cutters to the Royal Navy (in addition to the fifty destroyers), and authorized other measures to provide the British cargo ships and tankers, to reinforce the British oil “shuttle” in American waters, and to repair British warships in American shipyards. Dönitz characterized these measures as “a chain of breaches of international law” and urged Hitler to lift the tight restrictions on attacking American ships. Absorbed with planning operations in the Soviet Union, the Balkans, and the Mediterranean Basin, Hitler was still wary of antagonizing the Americans and risking open warfare with them, and rejected the proposal.