Ironically, at the time Churchill proclaimed the “Battle of the Atlantic,” the U-boat force was in the worst shape since the beginning of the war. On March 1, 1941, there were only eight German U-boats in the North Atlantic, including a new Type IID duck, U-147. Five U-boats, including U-147, patrolled between Iceland and Scotland. Two others patrolled near Rockall Bank: Prien in U-47 and Kretschmer in U-99. The eighth U-boat, Heilmann in U-97, was out of torpedoes and assigned to weather reporting.
There was no help on March 1 from the Condors, but after dark, Erich Topp in the VIIC U-552 ran into the inbound convoy Halifax 109, which was approaching the coast of Scotland, leaving little sea room. Topp broadcast an alarm and with his last three internal torpedoes sank a 12,000-ton British tanker, Cadillac, his first success in U-552. A new VIIC, U-70, commanded by Joachim Matz, age twenty-seven, from the duck U-59, merely eight days out of Helgoland, arrived and set up on the Cadillac, only to see Topp blow it up in his face. Gerd Schreiber came up in the VIIC U-95 and sank two ships for 11,100 tons. Reinhard Hardegen in the duck U-147 sank a 4,800-ton Norwegian freighter, then returned to Germany.
One of two Condors staging from Norway reported an outbound convoy and attacked on the morning of March 2. Dönitz directed six of the seven oceangoing boats in the hunting grounds to form a north-south patrol line west of Rockall Bank. While the boats were moving into position through a dense fog on March 3, Condors scoured the probable course of the convoy but saw nothing. Nor did the near-blind boats.
After a hurried analysis of this failed operation, Dönitz ordered a drastic—and “lamentable”—change in Condor operations. Concluding that when Condors openly attacked a convoy they forced it to make a drastic alteration in course to avoid the converging U-boats, Dönitz barred Condors from attacking convoys. Henceforth they were only to spot and report convoys and make every possible effort to remain undetected, restrictions that hardly pleased the Condor crews.
The next day, March 4, a Condor reported another outbound convoy. It was not clear from the position report whether this was the same outbound convoy or a new one or if the position report was accurate. Nonetheless, Dönitz redeployed the six boats in a patrol line farther west, adding to it the U-A, commanded by Hans Eckermann, en route from Germany to Lorient to stage to West African waters. After the line was in place, on March 5, Gerd Schreiber in U-95, in the center of the line, inexplicably broke radio silence to report his accumulated sinkings. Assuming the British had DFed U-95’s report and would alter the convoy’s course to avoid him—as well as the whole patrol line—Dönitz logged that Schreiber had made “an extremely clumsy mistake.” Dönitz may have been correct; the convoy got away.
The failure to intercept either of these two outbound convoys led to a more detailed analysis of Condor/U-boat operations. The study revealed that in two months the U-boats had benefited only once (February 19-20) from Condor convoy reports. Almost without exception, Condor reports were incorrect as to the positions and courses of the convoys. Besides that, it took too long to redeploy the boats. By the time they reached the most likely interception line based on the reported convoy course (whether accurate or not), the report was twenty-four hours old and not reliable. Dönitz therefore directed that until better means of submarine/aircraft position reporting and cooperation could be found, “no more U-boat operations” were to be “undertaken on aircraft reports.” Condors were to continue patrolling and reporting convoys for the benefit of all German forces and they were again allowed to attack convoys on sight.
On March 6, Dönitz redeployed the boats. Five VIIs formed a north-south patrol line west of Rockall Bank, and the U-A went west to relieve U-97 as the weather reporter. The patrol line had only just formed when Prien in U-47 encountered and reported an outbound convoy. He shadowed and broadcast beacon signals to bring up the other boats. Dönitz directed three other boats of the patrol line—U-37 (Clausen), U-70 (Matz), U-99 (Kretschmer)—and also the westbound U-A to converge on Prien’s signals. This was convoy Outbound 293, escorted by two destroyers, Wolverine and Verity, and two corvettes, Arbutus and Camellia.
Prien in U-47 and Kretschmer in U-99 met in moderate, misty seas at 6:00 P.M. Talking by megaphone across the water, they planned a joint attack on the convoy. As they were talking, the two destroyers—both with Type 286M radar—loomed out of the mist: Wolverine, commanded by James M. Rowland, and Verity. Patrolling ahead of the convoy, the destroyers caught Prien and Kretschmer by surprise, forcing both U-boats to crash-dive. The destroyers found Prien and worked him over with depth charges. Kretschmer went deep and slipped away. Later in the night, both boats surfaced.
Meanwhile, Joachim Matz in the new U-70 arrived, taking up position in the dark ahead of the convoy. Matz had been in the Atlantic all of two weeks and had yet to fire a torpedo. At 0430 hours on March 7, he attacked, firing all four bow torpedoes at four different ships. He later claimed that he had hit and sunk all four (for 35,500 tons) but in reality, he had hit but only damaged the 6,400-ton British freighter Delilian and possibly the 6,600-ton British tanker Athelbeach. Ten minutes later, Prien, who was low on torpedoes, radioed Dönitz an updated position report, then attacked, choosing the largest ship in the convoy, the 20,640-ton Norwegian whale-factory ship, Terje Viken, converted to a tanker. Prien hit her with two torpedoes, but she was in ballast and thus very hard to sink. Although damaged, she sailed on.
Having reloaded his four bow tubes, at 0600 Matz came in for a second attack. He saw the damaged Terje Viken and fired three torpedoes at her, but all three missed. He was on the point of firing his fourth bow tube when another boat hit the factory ship with one torpedo. That shot came from Kretschmer in U-99. Kretschmer then fired one torpedo at another ship, but missed. Swinging about, he shot three torpedoes at the possibly damaged tanker Athelbeach, which hit but did not sink her. To save torpedoes, Kretschmer went after the crippled Athelbeach with his deck gun, but the gunners were not successful and he was forced to expend another torpedo, which finally put the tanker under.
The four escorts, under tactical command of James Rowland in the destroyer Wolverine, reacted aggressively. While the convoy was making a sharp evasive turn to port, they lit up the area with star shells and commenced hunting U-47, U-70, and U-99, all of which were in close proximity. The corvette Arbutus got the first sonar contact at 0448 hours and dropped depth charges, calling up the other corvette, Camellia. The destroyers Wolverine and Verity spotted U-boats and drove them under, dropping depth charges.
Matz, who still had one torpedo in a bow tube, closed submerged on the 7,500-ton Dutch tanker Mijdrecht. He hit and damaged the ship, but the Dutch captain saw U-70’s periscope ahead and turned at it to ram. His aim was good; Mijdrecht’s bow cleaved into U-70’s conning tower, smashing the bridge and periscopes and throwing the boat down and under as though it had been hit by a huge wave. Mijdrecht was not seriously damaged; her crew repaired the hole made by the torpedo and sailed on.
The collision caused leaks in U-70’s conning tower but no serious damage to the pressure hull. Matz hauled off into the mist to surface and assess the topside damage. At 0815 hours, the corvette Camellia spotted U-70 about four miles ahead and charged, forcing Matz to crash-dive. Camellia radioed an alarm, which brought up the other corvette, Arbutus. Camellia’s sonar failed, but she fired a salvo of six depth charges “by eye.” At 0925, Arbutus arrived, got a firm sonar contact, and in two quick successive attacks, fired twelve depth charges. Acting on Arbutus’s sonar information, Camellia also attacked again, firing another six charges, but lacking sonar, Camellia was of little help and she was ordered off to protect the damaged ships and to rescue survivors.
Arbutus doggedly pursued U-70, firing five more salvos of six charges over the next three hours. In all, U-70 took fifty-four charges from Arbutus and Camellia. The last three attacks by Arbutus fatally wrecked U-70. She flooded aft and went out of control, assuming a 45-degree up-angle. Matz crammed all available men into the bow compartment, but to no avail. The boat slipped down by the stern to 656 feet. Unable to regain control, Matz blew all ballast tanks with his last bit of high-pressure air and surfaced to scuttle. Seeing her, Arbutus came in to ram, firing her 4” deck gun and other weapons.
When Matz opened the conning-tower hatch, the pressure inside the boat was so great that it blew him and five other men straight up into the smashed bridge. Seeing the U-70 crew jumping into the water, Arbutus veered off and dropped two life rafts. With hatches and sea cocks open, the U-70 plunged down by the bow and sank. Arbutus fished Matz and twenty-five other men from the water. Twenty Germans died in the sinking.
The movements of Prien’s U-47 and Kretschmer’s U-99 that day are not certain. The destroyers Wolverine and Verity apparently made sonar contact and repeatedly attacked both boats. Kretschmer reported later that an “old type” destroyer drove him under and held him down for about nine hours, delivering fifty-one depth charges. It is possible that Prien in U-47 was caught in the same barrage and was destroyed.
Nothing more was ever heard from Prien. That night Prien—as well as Matz—failed to respond to requests from Dönitz for position and sinking reports.
Later that same evening, March 7, at 10:00 P.M., Hans Eckermann in U-A made contact with the convoy farther west and radioed a position report. Nikolaus Clausen in U-37, who had not yet found the convoy, requested beacon signals. Eckermann broadcast another position report a half hour after midnight, March 8. Soon after that, he closed the convoy and attacked, firing two torpedoes at the lead ship in the starboard column. Eckermann believed both torpedoes had hit, but only one did, causing slight damage to the 5,300-ton British freighter Dunaff Head.
At that time the destroyers Wolverine and Verity were steaming on the starboard side of the convoy. The U-A lay directly in the path of Wolverine. Hoping to catch the U-boat by surprise and ram her, Wolverine’s, captain, James Rowland, refrained from firing star shells or speeding up or changing course. Thirteen minutes later Rowland saw “smoke resembling diesel exhaust” dead ahead and his sonar operator reported a contact. Three minutes later Wolverine spotted a wake, then the U-boat itself “zigzagging wildly at high speed.” Rowland rang up full speed but withheld gunfire, still hoping to ram. But Verity spoiled the plan, firing star shells, which lit up the area and forced the U-boat to crash-dive about three-quarters of a mile ahead of Wolverine.
Rowland reduced speed but was unable to make sonar contact or estimate where the boat had dived. He and Verity reversed course. Seven minutes later Wolverine and Verity obtained “firm” sonar contacts. Rowland ran in and fired two separate salvos, comprising eighteen depth charges. He followed up with three more modified salvos, a total of six depth charges, and dropped a flare to mark the U-boat’s position. There was no apparent result from these twenty-four depth charges, but Rowland’s engineer reported that he had “unmistakably seen and smelt shale oil,” indicating possible damage to the U-boat’s fuel tanks.
In an analysis of this attack, the British, unaware that U-A had torpedoed Dunaff Head, were to claim that the U-boat Wolverine and Verity attacked was Prien’s U-47, which they sank. No positive evidence ever developed to support this claim. Possibly it was true. Possibly Prien chased the convoy westward during that evening. But it does not seem likely. He had already attacked five ships by torpedo on this patrol (four on February 26); he could not have had enough torpedoes left to justify pursuit and another attack. He made no contact reports that night; if his radio was out of commission, there would have been no point in chasing the convoy, unless Prien thought the radio might be repaired in time to be of use. Significantly, Otto Kretschmer, who had an ample supply of torpedoes, did not chase the convoy westward that night.
Eckermann in U-A later reported that immediately after firing his torpedoes (at Dunaff Head) the boat was subjected to a brutal depth-charge attack. This was doubtless delivered by Wolverine and Verity. The U-A’s first watch officer, Carl Emmermann, remembered: “We got away and surfaced in the dark close by the destroyers. Eckermann wanted to run off at high speed on the diesels, but I persuaded him to creep away quietly on the electric motors, so we wouldn’t make smoke or noise. We escaped by the skin of our teeth.” Later, when he was well-clear, Eckermann radioed Dönitz that U-A had suffered “heavy” depth-charge damage and that he was compelled to abort to Lorient.
Wolverine continued the hunt tenaciously. Rowland wrote that at about 0410 Wolverine picked up the noise of a U-boat on the surface and commenced a chase at 20 knots, slowing occasionally to 8 knots to listen on sonar in order to reestablish the U-boat’s bearing. After one hour—a twenty-mile chase—Wolverine spotted the U-boat dead ahead and Rowland prepared to ram at full speed. But the U-boat crash-dived “200-300 yards” ahead. Passing over the spot, Rowland saw a V-shaped “rush of bubbles” intensified by “phosphorescence.” Based on six years of prior duty in submarines, Rowland was positive the bubbles were caused by air from venting ballast tanks and that he had a U-boat at shallow depth, directly under his keel. He turned hard to port, and at four-second intervals he fired ten depth charges set for 100 feet.
Unless Rowland had been chasing a phantom or a whale or a school of porpoises, his depth-charge salvo should have blown the U-boat to smithereens, releasing wreckage and bodies. But to Rowland’s “great disappointment,” no wreckage of any kind rose to the surface. Rowland saw a mysterious “faint orange light” for “about ten seconds” near the spot where the depth charges exploded, but he could not pause to investigate because sonar still had “firm contact” on the target. He circled around, maintaining the sonar contact, and continued dropping single depth charges sporadically until 0755, but ceased further attacks when “porpoises were sighted in the vicinity at daylight.”
So many false claims of U-boat sinkings had been made that the Admiralty had established strict criteria for crediting a positive kill. Wolverine’s evidence was not sufficient to meet the criteria. However, when it discovered from Matz and others captured from U-70, and from other sources, that Prien had been in the vicinity and had not returned from this patrol, the Admiralty’s Assessment Committee accepted this “circumstantial evidence” and ruled that Wolverine “probably sunk … U-47, commanded by Prien.” Doubtless another factor that entered into this weak and uncertain assessment was the propaganda benefit to be gained by crediting a British captain and crew with destroying Germany’s most famous U-boat ace. It is more likely that Prien was lost on March 7 by depth-charge attack, by a circular-running torpedo, by a crew error, or by a catastrophic structural failure in U-47. It is also possible that U-47 was lost by unknown causes (mine, crew error, etc.) en route to Lorient with a defective radio.
Whatever the case, the four escorts of convoy Outbound 293 deserved highest praise and awards. Their aggressive U-boat attacks had not only fended off Germany’s two foremost U-boat aces with slight losses in ships* but also had sunk one of them, as well as the U-70, and had nearly sunk U-A. No other escort team had ever done as well. Moreover, U-47 and U-70 were the first confirmed U-boat kills by British forces since the loss of U-31 on November 2, ending a humiliating dry spell of more than four months.
Dönitz felt “great anxiety” when U-47 and U-70 failed to respond to inquiries. But he could not permit himself to believe that both boats—the invincible Prien in particular—had been lost. He consoled himself with the possibility that Prien and Matz had radio failures, that any day Prien would appear off Lorient with new battle pennants flying from his raised periscope. And yet …
There was better news from southern waters. Very, very good news, in fact. The three Type IXB boats en route to Freetown, Sierra Leone, U-105, U-106, and U-124, had refueled March 4 to March 6 from the German tanker Corrientes, in the Spanish Canaries, then continued southward. On March 6 the lead boat, U-124, commanded by Georg-Wilhelm Schulz, met Gneisenau and Scharnhorst off the African coast. The next day, the battle cruisers found inbound convoy Sierra Leone 67, escorted by the British battleship Malaya and other vessels. Inasmuch as the German ships were still under orders not to engage British capital ships, they pulled off and U-124 was alerted. The plan that evolved was for U-124 and U-105 to close the convoy and sink Malaya, so that Gneisenau and Scharnhorst could return and attack the merchant ships. If any ships survived this combined assault and slipped by, the U-106, which was trailing the other boats by several days, might intercept them farther north.
The plan did not work out, but the U-boats nonetheless had great success. Attacking first in the early hours of March 8, Georg Schewe in U-105 sank a 5,200-ton British freighter. Sailing into the middle of the panicked convoy, Schulz in U-124 fired all six tubes (four forward, two aft) over a period of twenty-one minutes, at six different ships. He claimed sinking five of them for 33,000 tons and leaving another of 6,000 tons “in sinking condition.” Postwar analysis credited him with sinking four British freighters for 23,300 tons, a remarkable salvo. Later, Jurgen Oesten in U-106 arrived at the same place and sank a 7,500-ton British freighter. Total confirmed results: six ships sunk for 36,000 tons.
The Malaya was not touched, therefore Gneisenau and Scharnhorst could not attack the convoy. They refueled from their supply ships and set a course northwestward to attack Halifax convoys. The U-124 cruised west to meet the merchant-ship raider Kormoran to obtain torpedoes and fuel, and to await a rendezvous with the Germany-bound “pocket” battleship Admiral Scheer, to deliver her a spare part for her primitive radar. The U-105 and U-106 proceeded directly to Freetown.