Hitler’s U-Boat War- The Hunted 1942-45

by Clay Blair

  Nine days later, at about 4:00 A.M., May 14, the Ritterkreuz holder Siegfried Koitschka in the veteran U-616 came upon the next westbound convoy, GUS 39, off Cape Tenez between Algiers and Oran. He shot T-5s and hit and damaged two British ships in ballast, the 10,600-ton tanker G. S. Walden and the 7,200-ton Liberty ship Fort Fidler.

  Four modern American warships of the convoy escort fell out to hunt the U-boat. These were the destroyer Hilary P. Jones and the destroyer escorts Bostwick, Bronstein, and Vance, the last manned by a Coast Guard crew. After an eight-hour hunt, the Hilary P. Jones got a sonar contact (shortly after noon), but her two attacks produced no results.

  During that afternoon, British naval authorities launched “Operation Swamp,”* a relentless hunt for U-616. For that purpose, Hilary P. Jones of the convoy remained at the scene. She was joined by two American hunter-killer groups, one of three destroyers (Gleaves, Macomb, Nields) and another of four destroyers (Ellyson, Emmons, Hambleton, Rodman), plus numerous Leigh Light-equipped Wellingtons of British Squadron 36.

  That night, May 14, Koitschka surfaced at about 11:00 to charge batteries. Thereupon, a Wellington of British Squadron 36, piloted by J. M. Cooke, attacked into 20mm flak and drove the U-boat under with six depth charges, then alerted the eight destroyers. About an hour later, the nearest one, Ellyson, came up, got a solid sonar contact, and attacked U-616 with more depth charges. The missiles of the Wellington and Ellyson damaged a fuel-oil tank of U-616, and she began to trail an oil slick that at dawn was quite visible.

  While Allied ASW forces continued the hunt, Koitschka took U-616 deep and remained virtually immobile during the daylight hours of May 15. By nightfall his battery was dangerously low and the air in the boat was foul, so he surfaced about midnight. Two more Leigh Light-equipped Wellingtons of British Squadron 36 got U-616 on radar and drove her under again. Later, however, Koitschka was able to surface undetected and charge batteries.

  During the daylight hours of May 16, Koitschka again went deep and remained virtually immobile. As a consequence, the Allied hunters lost contact. After dark, at about 9:00 P.M., Koitschka surfaced again to charge batteries but an hour later, another Wellington of Squadron 36, piloted by H. R. Swain, got a radar contact and drove the boat back under with depth charges.

  On the heels of this Wellington attack, the destroyer groups (less Hilary P. Jones) raced to that position. Shortly after midnight, May 17, Koitschka surfaced again to charge batteries. The destroyer Macomb got the boat on radar, then illuminated her by searchlight and opened fire with her main battery. Koitschka crash-dived and evaded with violent maneuvers, but Macomb and Gleaves hung on and carried out depth-charge attacks. The other five destroyers joined in the depth-charging and finally, at about 8:00 A.M.—seventy-six hours after Koitschka hit and damaged the two British freighters of convoy GUS 39—the Hambleton loosed a salvo set for six hundred feet, and this drove U-616 to the surface.

  Those of the seven destroyers that could bring guns to bear opened fire. Koitschka scuttled and abandoned ship. Ellyson and Rodman rescued the entire German crew—six officers and forty-seven men—bringing to a conclusion the longest and most relentless U-boat hunt of the war.

  As in the case of Albrecht Brandi, Ritterkreuz holder Koitschka had registered an impressive list of claims. He told his Allied interrogators that he had sunk “about 45,000 tons of shipping,’’ which included “nine destroyers, two submarines and two landing ships.” His claims listed in German records were likewise impressive: six destroyers, two LSTs, two Italian submarines, and seven freighters sunk or probably sunk. Like Brandi, Koitschka’s confirmed score was startlingly less: one destroyer definitely sunk (the American Buck), one LST “probably sunk,” and the damage to the two British freighters of GUS 39 that led directly to the loss of U-616.

  As the seven destroyers of the Swamp/Monstrous operation were preparing to enter Mers-el-Kébir, the seaport of Oran, at about 1:00 P.M. on May 17, the destroyer Ellyson, which had most survivors of U-616 on board, reported that three torpedoes had missed her astern. These were fired by the newest—and last— U-boat to enter the Mediterranean, the U-960, commanded by Günter Heinrich, who had passed through Gibraltar Strait on May 9. He dived to about six hundred feet and eased away toward Toulon.

  Allied authorities immediately launched another Swamp/Monstrous operation. Five American destroyers (Benson, Ludlow, Madison, Niblack, Woolsey) steamed out of Mers-el-Kébir and Coastal Command aircraft of British Squadrons 36 and 500 saturated the area. After dark, Heinrich surfaced U-960 and continued toward Toulon. One Wellington of the search group was forced to abort with mechanical defects, but another of Squadron 36 “chanced upon” U-960 in the early hours of May 18 and drove her under.

  The Allied forces converged on the Wellington’s position report and hunted all day May 18, but found no trace of the U-boat. However, late in the evening of that day, another Wellington of British Squadron 36, piloted by the Canadian K.H.N. Bulmer, got a radar contact and gave the alarm. Heinrich dived but when he resurfaced three hours later at about 1:30 A.M. on May 19 to charge batteries, the Canadian crew of the Wellington was still circling. Bulmer again gave the alarm and this time dropped lighted marker buoys for the destroyers Ludlow and Niblack, which were not far away.

  In a series of cool and deliberate attacks over four hours, Ludlow and Niblack pounded U-960 with depth charges. These wrecked the boat and forced Heinrich to surface and scuttle. When he came up at about 7:00 A.M.—forty-two hours after shooting at Ellyson—Ludlow and Niblack opened fire with main batteries, and a Ventura of British Squadron 500, piloted by Canadian E.A.K. Munday, attacked with depth charges. Finally, Niblack closed the abandoned hulk of U-960 and finished her off with a salvo of depth charges. She and Ludlow rescued twenty of the fifty-one Germans of U-960, including Heinrich, who was wounded, and three other officers.

  The last U-boat success in the Mediterranean occurred at about noon that same day, May 19. Off the “toe” of Italy in the Ionian Sea, the veteran U-453, commanded by Dierk Lührs, sank from a local convoy, HA 43, the 7,200-ton British Liberty ship Fort Missanabie with a salvo of three torpedoes. Three British destroyers pounced with depth charges and Hedgehogs: Liddesdale, Tenacious, and Termagant. Lührs went to the bottom (590 feet) and lay doggo the night of May 19-20. Believing he could escape, at dawn the next day Lührs broke U-453 loose from the bottom and attempted to flee. However, the British warships were waiting, and at noon they commenced a relentless depth-charge attack that went on for about twelve hours.

  These missiles wrecked U-453 and forced her to the surface to scuttle shortly after midnight on May 21. As the fifty-one Germans of the crew leaped over the side, the destroyers opened up with main batteries and achieved several hits before the U-boat disappeared. The gunfire killed one German. The Tenacious and Termagant picked up fifteen men and took them to Taranto; the Liddesdale recovered the other thirty-four Germans and took them to Palermo.

  The sinking of the Fort Missanabie was the- last confirmed success of the Mediterranean U-boat force. From June 1, the remaining eleven boats were mostly shipyard-bound for battle-damage repairs and installation of snorts. None survived. Army Air Forces raids on Toulon on July 5 and August 6 destroyed five boats (U-471, U-586, U-642, U-952, U-969). After the invasion of southern France (Dragoon) on August 15, three more U-boats were scuttled in or off Toulon (U-230, U-466, U-967). Allied forces destroyed the remaining three boats (U-407, U-565, U-596, all snort boats based at Salamis) in September.

  Altogether, sixty-two Type VIIs passed through the Strait of Gibraltar into the Mediterranean Sea during the war and none survived. Operating under extremely hazardous conditions, these boats sank a confirmed total of thirty-seven warships and 137 merchant ships for about 503,000 gross tons. The confirmed warships:

  1 battleship (HMS Barham)

  2 aircraft carriers (HMS Ark Royal and Eagle)

  4 cruisers (HMS Galatea, Hermione, Naiad, and Penelope)

  1 large mine
layer (HMS Welshman)

  16 destroyers or destroyer escorts*

  1 frigate (HMS Cuckmere)

  1 sloop (HMS Parramatta)

  1 corvette (HMS Silvia)

  3 minecraft (HMS Hebe and Hythe; USS Skill)

  5 LSTs (four British, one American)

  2 ASW trawlers (HMS Vissiliki and Jura)

  PATROLS TO AND FROM THE FAR EAST

  During the period from January 1 to June 1, 1944, Control sailed sixteen boats to the Far East and eight boats from the Far East* to France. These carried supplies to the German U-boat base at Penang and scarce commodities, such as rubber, tin, wolfram (tungsten), quinine, and opium from Penang to France. Some conducted antiship patrols along the way, but only eight of the twenty-four completed their missions. In another great U-boat slaughter, Allied ASW forces sank eleven and compelled five to abort.

  To facilitate the extraordinarily long voyages of these boats, as previously related Control directed the German surface tanker Charlotte Schliemann to a convenient position in the Indian Ocean. The Allies learned of these plans from Enigma decrypts and ordered a small British hunter-killer group, consisting of the light cruiser Newcastle and the destroyer Relentless, to the scene. Reinforced by seven British Catalinas from Mauritius, on the night of February 11-12, Relentless opened fire on Charlotte Schliemann, and the Germans scuttled and abandoned ship. The British ships picked up forty-one crew of the tanker, †

  The loss of this tanker disrupted and confused German operations in the Indian Ocean. The first U-boat to feel the impact was the IXC40 U-532, commanded by Otto-Heinrich Junker. He had sailed from Penang to France on January 4 with a load of tin, rubber, wolfram, quinine, and opium. Patrolling home via the coast of India, he had sunk the 7,200-ton American Liberty ship Walter Camp and damaged the 7,300-ton British freighter Triona, but to get home, he had to refuel.

  Junker arrived at the rendezvous with Charlotte Schliemann on February 12. He reported to Control four days later that he had found no sign of the tanker but had seen two Catalinas. That led to the suspicion that the rendezvous had been compromised and that the Charlotte Schliemann was lost. Nonetheless Control directed U-532 to a new rendezvous with the tanker on February 19. In case the tanker was lost, Control ordered Wilhelm Spahr in the IXD2 cruiser U-178, also returning to France with cargo, to go to the rendezvous prepared to give Junker fuel, after which Spahr could resume his voyage to France.

  Junker reported on February 22 that he could not find Charlotte Schliemann and assumed she was lost. Control concurred and ordered the surface tanker Brake-^-the last German tanker in the Indian Ocean—to provide support for the U-boats at a new rendezvous on or about March 11. Junker in U-532, who had received some fuel from Spahr in U-178, but not enough to reach France, was to meet Brake and refuel, along with three other IXC40s (U-168, U-183, U-188), also homebound from Penang to France with cargoes of tin, rubber, wolfram, quinine, and opium.

  Commanded by Helmut Pich, the U-168 had originally sailed from Penang on January 28. Five days out, the first watch officer, Hans-Georg Stenger, had come down with appendicitis and Pich had to return to Penang. He had resailed on February 7 with, as he remembered, a cargo consisting of about one hundred tons of tin, wolfram, quinine, and opium. Patrolling home via India, Pich had sunk two ships (the 1,400-ton British repair ship Salviking, and a 4,400-ton Greek freighter) and had damaged the 9,800-ton Norwegian tanker Fenris.

  The U-188, commanded by Siegfried Lüdden, had sailed from Penang on January 9 with a similar cargo. Patrolling home via the Arabian Sea and Gulf of Aden, Lüdden had achieved astonishing results for this period of the war: seven confirmed British freighters for 42,500 tons sunk by torpedo, plus seven dhows (sailboats) with cargoes of cotton, sunk by flak guns and ramming.* Upon receiving Lüdden’s report, Dönitz had immediately awarded him a Ritterkreuz.†

  Commanded by Fritz Schneewind, the U-183 had sailed from Penang on February 10 with the usual cargo. Patrolling home via the Maldives and Ceylon, Schneewind had mounted attacks on two British vessels. On February 29, he had sunk the 5,400-ton freighter Palma. On March 9 he had hit the 7,000-ton tanker British Loyalty, anchored off Addu Atoll in the Maldives. She burned and sank to the bottom. Efforts to salvage her failed, and she was scrapped.

  The first boat to arrive at the rendezvous with Brake was Lüdden in U-188. He replenished and refueled on March 12 and left immediately for Bordeaux, France. Next on the scene that day was Junker in U-532, who had been dawdling around in the area for a full month. Last to arrive was Pich in U-168. Junker and Pich took on fuel, but Junker got no lube oil and Pich did not get a full load of either fuel or lube oil.

  “The captain of Brake was very nervous and rushed,” Pich remembered. “Before we finished up he broke off operations and instructed us to meet him at another rendezvous.” Pich and his crew “had very bad feelings about all this” and were also “very nervous.”

  Not without reason. Allied codebreakers had also provided good information on this rendezvous. Despite Churchill’s warnings against using Enigma decrypts tactically, the Admiralty had sent out another hunter-killer group to spoil the party. It was composed of the “jeep” carrier Battler, the heavy cruiser Suffolk, the light cruiser Newcastle, and the destroyers Roebuck and Quadrant As though on routine patrol, aircraft from Battler “spotted” Brake and the three U-boats. The British destroyer Roebuck raced up. Upon sighting the aircraft from Battler, the Germans realized they had been detected, took to the lifeboats, and scuttled Brake. Pich in U-168 dived away but later rescued all 135 Germans from Brake (bringing the total personnel on U-168 to 190) and returned to the Far East in company with Junker in U-532.

  It was imprudent to use Enigma decrypts tactically to sink the last two German tankers, Charlotte Schliemann and Brake, at U-boat refueling meets in the vast reaches of the Indian Ocean within a period of one month. The German skippers and U-boat Control agreed that U-boat Enigma had been “systematically compromised.” In a top-secret message, U-boat Control therefore immediately initiated an “emergency procedure” to outwit Allied codebreakers. Assuming that the Allies had somehow obtained current keys, on March 13 these settings were canceled. Until new keys could be distributed, every U-boat at sea was to set the four rotors and other keys to match the first letters of the given names and surnames and the home addresses of the radio-electrician and third watch officer, information known to U-boat Control from the crew sailing lists.

  In this top-secret message, U-boat Control instructed all skippers to destroy the messages after committing the modifications to memory or “unobtrusively” making a private memo to be shown only to officers. Importantly, the message also informed skippers that “major changes in cipher settings” were to be made “shortly.”

  This news caused deepest concern and pessimism among Allied codebreakers at Bletchley Park and OP20G in Washington. The senior hands were furious that the Admiralty had acted so thoughtlessly against the tankers. Sheepishly the Admiralty got off a message on March 16 to all recipients of naval Enigma decrypts, informing them that the Germans had “modified” U-boat Enigma and that all commands were to steer clear of U-boat refueling meets until further notice.

  Lüdden in U-188 continued his voyage to France, but he needed help from other U-boats. Near Cape Town on March 22, he met the outbound VIIF supply boat U-1062 and got the latest Enigma keys. One month later, on April 22, near St. Paul Rocks in the South Atlantic, he met Kurt Freiwald’s outbound IXD2 cruiser U-181, got lube oil and took on board a sick engineer from U-181. Three hundred miles farther north, on April 26, Lüdden met the outbound IXC U-129 and got a Naxos radar detector. On April 30, Control directed Lüdden to run at maximum speed to render assistance to a “stranded” IXC, U-66, near the Cape Verde Islands. Lüdden met that boat on May 2 and gave her some fuel and food, but he was attacked by carrier aircraft during the transfer. Lüdden’s radio then failed and he was unable to notify Control of this meet—and of the presence of carrier aircraft—
and inched onward to Bordeaux, where he arrived on June 19, to the surprise of Control, since it had assumed from Lüdden’s radio silence that U-188 had been sunk.

  The loss of Brake placed two other U-boats in jeopardy. One was the home-bound IXC40 U-183, commanded by Fritz Schneewind, loaded with the usual cargo. His batteries were in poor condition. He hoped to get help from Brake but he had to turn about and return to Penang. The other was the ex-Italian Cappellini, redesignated U-IT24, commanded by Heinrich Pahls, which was France-bound with the usual cargo of tin, rubber, tungsten, quinine, and opium. Pahls linked up with Junker in the IXC40 U-532, got fuel, and returned independently to Penang. Thus Enigma information enabled the Allies to thwart the sailing to France from the Far East of four out of six U-boats with cargoes and to sink the valuable German surface tankers Charlotte Schliemann and Brake*

  In Penang, the commander of the IXD2 cruiser U-183, Fritz Schneewind, reported that all but 30 percent of his battery had disintegrated. Since he could not return U-183 to France with only one-third of his battery operable, U-boat Control directed him to make a short patrol to Ceylon and the Maldives in the Indian Ocean, then take the boat to Japan, where the battery could be replaced or repaired, or so it was hoped.

  In compliance with these orders, Schneewind sailed from Penang on May 17 and reached the western limit of his patrol area near the Maldives on June 5. That day he sank the 5,300-ton British freighter Helen Moller. Per further orders, on June 24 Schneewind met the IXC40 U-843, outbound from France to Penang under the command of Oskar Herwartz, and got two sets of new Enigma keys and Naxos gear. Schneewind was to meet and give one set of Enigma keys to Karl Albrecht in the VIIF supply boat U-1062, homebound to France. However, a broken air compressor compelled Albrecht to abort to Penang. The two boats canceled the rendezvous and returned to Penang, Albrecht on July 2, Schneewind on July 7.