by Clay Blair
GERMAN PLANS AND NAVAL RESOURCES
Inasmuch as the Allies had proclaimed a policy of “unconditional surrender” at the Casablanca conference, the leaders of the Third Reich believed that they had no choice other than to fight to the finish regardless of the cost and the consequences. Vital for his fight to the finish, Hitler believed, was the development of a large family of exotic new weapons. He therefore gave the highest priority to jet-and rocket-powered aircraft and land-based radar and radar detectors to counter Allied heavy bombers; a new heavy tank for the ground forces; the V-l cruise and V-2 ballistic missiles; the small Type XXIII and big Type XXI “electro boats”; improved looping and homing submarine torpedoes with more powerful warheads; a “pressure” mine, activated by the wave action of surface vessels; and “midget” submarines that could attack Allied invasion forces with defensive mines or torpedoes.
Amid growing tension, shifting loyalties, and defections in the German high command, Admiral Dönitz assured Hitler and the German citizenry that, come what may, the Kriegsmarine would not waver in its support of the national government. Meeting with the Führer on two occasions in January 1944, at his command post in East Prussia, Wolfschanze, Dönitz and Hitler agreed to a number of important policy matters.
• Assuming that an Allied invasion of Norway or France or—more likely— both places was to occur in the spring, the U-boat force was to go over to the defensive at once to mass the greatest possible strength to repel these operations. By an order issued on January 10, the Arctic U-boat force was to be increased to a total of thirty boats. Another large group of U-boats (group Mine, or Central), fresh from Germany, was to be held in readiness in southern Norway to repel an invasion of that area or Denmark. The Atlantic U-boat force was to accumulate a large ready force (group Landwirt) in Brest and in the Biscay ports to repel an invasion of France. Notwithstanding the general disappointment his U-boat crews had shown for snorts, Dönitz was to equip as many U-boats as possible with the device and hurry along the training of crews in its use.
• U-boat operations against Allied convoys in the Atlantic were to be continued from French bases but on a sharply diminishing scale as the likely invasion date approached. The main purpose of these operations was not so much to sink ships as it was to give crews battle experience, test new electronics and flak guns, and free up space in the U-boat pens in France for snort upgrades. Fitted with the Naxos radar detector and the new 37mm automatic flak gun, the U-boats were to continue operations in scattered groups but were to stay in the eastern Atlantic so that if necessary they could be quickly redeployed against the expected invasion forces. In addition, certain boats were to broadcast twice-daily weather reports for the benefit of the Luftwaffe raids on London and for those German air and ground forces earmarked for anti-invasion duties.
• The Atlantic U-boat force was to provide the Mediterranean U-boat force with another dozen boats to ensure that the Allies were not relieved of convoying in that body of water. The forty-one-year-old Werner Hartmann, crew of 1921, who had won a Ritterkreuz on U-37 in 1940 and had commanded the U-cruiser U-198 on a two-hundred-day cruise to the Indian Ocean, was appointed to relieve Leo Kreisch as commander of the Mediterranean U-boat force, effective January 1944.
• Patrols to remote areas by long-range Type IXCs, IXC40s, and IXD2 U-cruisers were also to continue, albeit on a modest scale. The single remaining XIV “milk cow” tanker in the Atlantic force, U-488, was to provide replenishment services for the Type IXs of this group in what was believed to be relatively safe waters west of the Cape Verde Islands. The new rules governing the rendezvous with U-tankers were to be followed to the letter. The tenth—and last—Type XIV tanker, U-490, delayed by the aforementioned accident in the Baltic and the installation of a snort and experimental gear for submerged refueling, was to be brought to the Atlantic as soon as possible.
• Owing to the great—and possibly decisive—offensive capabilities they promised, the small Type XXIII and big Type XXI “electro boats” were to be rushed to completion with maximum priority. Setbacks to the production of electric motors and diesel engines caused by Allied air raids and labor shortages were to be compensated for by higher production goals, faster repair of bomb damage to the factories, and yet another set of new restrictions on drafting shipwrights into the German Army. Although the problem of providing exotic fuels had not been overcome, work on the “Walter boats,” powered by a closed-cycle, hydrogen-peroxide engine, was also to continue at a high priority.
• In response to urgent requests from Dönitz, in order that the Luftwaffe could provide the oncoming “electro boats” with better information on Allied convoy movements, Hitler assured Dönitz that production of four-engine JU-290 aircraft was to be accelerated. However, Goring, citing priorities for other aircraft and shortages of materials, declared that an increase in JU-290 production was “impossible” By January 1944, only eight JU-290s were available to assist the Atlantic U-boat force in convoy locations and that number shrank rather than grew.
• The battleship Tirpitz, under repair in Altenfiord, was to remain in northern Norway as a “fleet in being” threat to tie down ships of the Home Fleet and to repel the expected Allied invasion of Norway. Consideration was given to moving the heavy cruiser Prinz Eugen from the Baltic to northern Norway for that purpose (and to prey on the Murmansk convoys), but finally she was held in the Baltic to fight Soviet forces advancing on Germany from the east.
• Owing to the heavy losses incurred while inbound and outbound to and from French ports, no more surface-ship blockade-runners were to sail to the Far East. All U-boats sailing to and from France and the Far East were to carry cargo. These included Japanese submarines,* the two failed IXDl U-cruisers, and the several big Italian submarines that had been converted for that purpose.
Some historians of the Battle of the Atlantic write that on January 1, 1944, the German U-boat force reached a peak wartime strength of 436 or 456 boats.† Seen at a glance, these figures imply an enormous threat to Allied shipping, but nothing could be further from the truth. Although the personnel of the U-boat arm remained resolutely and famously defiant, its strategy, tactics, and weaponry had failed—indeed, had failed abysmally. The only hope for a comeback rested on the possibility—repeat possibility—of obtaining at the earliest feasible date an effective search radar and radar detector, improved sonar, a reliable, high-angle automatic 37mm antiaircraft gun, better T-5 homing and other torpedoes, small and big “electro boats “ “Walter boats,” and a big fleet of Luftwaffe JU-290s.
The gross inflation of the .U-boat threat in early 1944 by many American and British historians, whether intended or unintended, doubtless arises from the picture presented in the war diary of U-boat Control. On January 1, 1944, it lists a total of 436 U-boats “in commission.” Included is a breakdown by types, assignment, and location:
Type school Workup War fronts
II(ducks) 33 0 6‡
VII 3 0 0
VIIB & C 48 140 120
VIIF(supply) 0 2 2
VIID 0 0 2
IXB & C 3 27 31
IXD2 0 8 5
XB(minelayer) 0 1 1
XIV(tanker) 0 1 1
XVII(tanker) 0 2§
—— — — —
Totals 87 181 168
The 181 boats in “workup” included a few boats assigned to R&D and a great many being fitted with new flak guns and bridge configurations to accommodate them, snorts and new electronics (Gema and Hohentwiel search radar with retractable “mattress” antennae), new radar detectors (Fliege for ten and Mücke for three centimeter wavelengths), and other gear.* Therefore, the only real threat posed by the U-boat arm on January 1, 1944, was the 168 boats at the warfronts. Not counting the six ducks in the Black Sea and two Type VIIF torpedo-supply boats in the Atlantic or Norway, the remaining 160 warfront boats were distributed as follows:
Many of the 122 Type VIIs in the three main war zones were undergoing battle-damage repairs,
modifications, or upgrades. For example, that figure includes in the Atlantic force the surviving seven Type VII flak boats (or would-be flak boats), which were reconverted to normal attack boats, and boats being fitted with snorts.
Owing to Hitler’s orders to substantially increase the Arctic, Norway, and Mediterranean U-boat forces, and to heavy battle losses, the Atlantic U-boat force shrank sharply from January 1 to May 1. In this period, only twenty-five new attack boats (sixteen VIIs, nine IXs) joined the Atlantic force, while forty-nine attack boats were lost (forty VIIs and nine IXs) and eight VIIs went to the Mediterranean. The decline in strength of the Atlantic force month by month:
As a consequence of this shrinkage and of the decision to recall and/or hold back boats to defend against the expected Allied invasion of France, the Atlantic force mounted an ever-shrinking number of patrols to its three principal areas of responsibility.
It is clear from this analysis that the large number of U-boats listed as “in commission” on January 1, 1944, means little or nothing, and that the U-boat peril to the Allies was yet another glaring instance of “threat inflation.” As a consequence of this inflation, the Allies continued to pour masses of new naval assets (“jeep” carriers, destroyers, destroyer escorts, frigates, sloops, corvettes, four-engine land-based aircraft, and so on) into the North Atlantic that might have been used to greater effect on other warfronts.
Historians generally omit or pass quickly over this phase of the U-boat war. It deserves greater attention, not so much for conventional reasons, but because it reveals a fascinating portrait of a once-proud naval force undergoing complete disintegration in the face of Allied ASW forces finally grown to maturity and to awesome size.
U-BOAT ACTIONS IN THE NORTH ATLANTIC: I
In mid-January 1944, Admiral Godt at U-boat Control sent a morale-boosting message to all U-boats. He gloated that from the onset of war to December 31,1943, German U-boats had sunk 19 million gross tons of Allied shipping, including 184 warships. The true figure by all Axis submarines was about 14 million gross tons, including seventy-eight warships. Therefore, German overall claims exceeded actual results by about 25 percent and warship claims were inflated over 100 percent.#
Most of the twenty-eight attack boats sailing to the North and Middle Atlantic areas in January were to join the two organized groups that were already in operation, Rügen and Borkum. Owing to the absence of tankers and the mounting threat of an Allied invasion, they, too, were held in the eastern Atlantic. The winter weather was ghastly. The captain of the old British destroyer Warwick, Denys Arthur Rayner, assigned to convoy escort, wrote that the weather was the “worst of the whole war” with “quite stupendous waves,” which, in his opinion, rendered U-boat operations “impossible.” *
The Allies enjoyed overwhelming intelligence and naval and air superiority in all areas. The four-rotor bombes of the U.S. Navy’s OP20G continued to read Enigma fluently and currently, enabling Allied authorities to evade or to track and attack U-boats. Inasmuch as the boats operated close to air bases in Iceland, the British Isles, Gibraltar, Morocco, and the Azores, Coastal Command was able to provide saturation land-based air cover in most of the threatened areas. In addition, the Royal Navy finally had a sufficient number of “jeep” carriers and hunter-killer groups to reinforce the escort of almost all convoys, inbound or outbound, although sustained operations of aircraft from “jeep” carriers in the North Atlantic in winter were, as always, iffy.
Two VIIs outbound from France in January incurred mechanical or structural failures:
The U-714, commanded by Hans-Joachim Schwebcke, which sailed from Lorient on January 11, reported a cracked exhaust manifold that could not be repaired. Schwebcke aborted to Lorient, but after repairs he was able to resail on January 20.
The ex-flak boat U-263, commanded by Kurt Nölke, which sailed from La Pal-lice on January 19, reported that “external fuel tank No. 2, portside, caved in during her deep dive test” and that the boat needed immediate help. Control rushed minecraft and aircraft into Biscay to assist, but they could find no sign of U-263 or its crew. Control attributed her loss to “mechanical failure”; the Allies speculated that she hit a mine.
Of the twenty-eight boats that did sail to the North Atlantic in January, quite a few carried out special missions.
• In compliance with Hitler’s orders, the VIIs U-343 and U-952, which sailed in December, entered the Mediterranean from January 3 to 5, and three more VIIs sailed to the Mediterranean in January.*
• To assist in locating departing convoys, Control assigned three experienced VIIs to closely reconnoiter likely ports. The U-260, commanded by Hubertus Purkhold, laid off Reykjavik, Iceland. She accomplished nothing and finished out the patrol reporting weather. On return to St. Nazaire, Purkhold left the boat for other duty. The U-386, commanded by Fritz Albrecht, and the ex-flak boat U-621, commanded by Max Kruschka, laid off in areas close to the mouth of North Channel. On the morning of January 13, a B-24 of British Squadron 59, piloted by the Australian Wesley G. Loney, attacked U-621 with eight depth charges and machine-gun fire that killed one man and wounded five. Forced to abort, Kruschka limped into Brest ten days later, on January 23.
• Apart from Purkhold in U-260, a half dozen boats fulfilled the urgent requirement for weather reporting.† Inasmuch as the twice-daily reports of these boats from the waters between Iceland and Greenland had been declared vital for the German anti-invasion forces in France, the patrols were maintained through the late winter and spring.
• The U-257, commanded by Heinz Rahe, sailed from St. Nazaire into Biscay to plant new Thetis radar decoys.‡ After completing this task, Control directed Rahe to meet the supposedly inbound (but actually lost) blockade-runner Rio Grande and give her updated charts.
When Control realized on January 27 that the Rio Grande was lost, it reassigned U-257 to be a weather reporter. While homebound from that mission on February 24, Rahe came upon Slow Convoy 153, guarded by Canadian Escort Group C-5 and British Escort Groups 3 and 6. Two of the sixteen-odd escorts, the new Canadian frigate Waskesiu and the British frigate Nene, detected U-260, blew her to the surface with depth charges, and Waskesiu sank her by gunfire. One of the nineteen German survivors who were rescued said that Rahe, who elected to go down with his ship, threw his life preserver into a dinghy to assist another man, then probably shot himself.
Notwithstanding the hostile winter weather, RAF Coastal Command maintained patrols in the Bay of Biscay and elsewhere in the eastern Atlantic. These operations included the thirty-six B-24s of the U.S. Navy’s Fairwing 7 assigned to Bombing Squadrons 103,105, and 110.* Although seldom mentioned in the histories of this period, the results in the first week of January were highly gratifying for the Allies. British aircraft over Biscay hit inbound and outbound boats.
Some air attacks on transiting boats:
• The VII U-625, commanded by Hans Benker, an Arctic transfer. When on January 2 a B-24 of British Squadron 224, piloted by J. E. Edwards, attacked, Benker damaged the plane and drove it off. When a second B-24 of Squadron 224, piloted by E. Allen attacked, Benker had the Naxos antenna on the bridge with its wire running to the control room through the conning-tower hatch. Under attack from Allen, Benker elected to dive but forgot to pull down the Naxos antenna wire, It caught in the hatch, prevented a seal, and caused flooding. Benker canceled the dive, and he and another German rushed to the bridge to unsnarl and reel in the wire. Benker’s order to cancel the dive was not heard and the boat went deep, leaving Benker and the crewman topside. They were not recovered. The first watch officer, Kurt Sureth, brought the boat into Brest on January 6. Control promptly told all boats that this tragedy was wholly unnecessary; firm hatch pressure on the Naxos antenna wire would snip it.
• The VII U-629, another Arctic transfer, commanded by Hans-Helmut Bugs. This was the boat that had rescued the crew of U-284, so nearly one hundred men were crammed belowdecks. In the early hours of January 4, a Leigh Light-equipped Wellington
of Polish Squadron 304, piloted by H. Czyzun, dropped six close depth charges and riddled the boat with 1,200 rounds of machine-gun fire. Heavily damaged, Bugs called for help and Control diverted two outbound boats, U-426 and U-539, and sent two minesweepers to assist. Fortunately for the hundred-odd German submariners in his care, Bugs reached Brest on January 5.
One of Bugs’s would-be assisters, the outbound U-426, commanded by Christian Reich, soon came to grief, hounded by enemy aircraft. On the morning of January 8, a Sunderland of Australian Squadron 10, piloted by J. P. Roberts, found the boat and during two runs into flak, dropped six depth charges and strafed. This fusillade destroyed U-426. Roberts reported “about forty men in the water” amid debris, but none survived.
• The VII U-415, commanded by Kurt Neide, who had sunk the British destroyer Hurricane on Christmas Eve. On the night of January 5, a Halifax of British Squadron 58, piloted by I.J.M. Christie, found U-415 and attacked with six near depth charges. Neide returned fire, then dived and escaped. He put into Brest the following day.