Hitler, Donitz, and the Baltic Sea (36 page)

In addition to the new-type U-boats, other causes for concern existed. The German submarines’ switch to transiting submerged and deploying individually led to a sharp reduction in signaling and thus of Allied decryption. Furthermore, the German Navy had begun experiments in flash transmission of radio messages. Such brief transmissions would have been devastating to Allied high-frequency direction finding as well as to their ability to intercept messages. In view of these developments, the new U-boats could have raised serious problems for the Allies. Churchill’s concern is evident in his request to Stalin at the Yalta Conference in February 1945 that the Soviets capture Danzig (one of three assembly sites for the Type XXIs) as quickly as possible. Signals intelligence provided the Allies with detailed information on U-boat specifications, though estimates on the number of these submarines available were often far from the mark.
⁴¹

When Dönitz had so jubilantly reported to Hitler on the new-type submarines in July 1943, Hitler had declared that it was vital to bring technologically advanced weapons to bear. He had added, however, that technicians must not make exaggerated demands that delayed their availability. Dönitz apparently remembered only Hitler’s enthusiasm. One of the most puzzling questions about these U-boats is why they took so long to become operational. Several reasons account for this. One is certainly that the navy had allowed itself to be surpassed technically, switching much too
late to submarines with high submerged speed.
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Another major cause of delays was damage inflicted by Allied aircraft. Air raids on shipyards caused serious problems, although bombing never halted U-boat construction. Air attacks on German shipyards and assembly yards destroyed and damaged a number of the new submarines as well as essential installations and equipment.
⁴³
Bombing caused greater delays, however, by blocking Germany’s inland waterways; the transport of U-boat sections from inland factories to assembly yards near the coast required passage through a number of canals. Bomb damage to the Kaiser Wilhelm, Mittelland, and Dortmund-Ems canals hampered the delivery of sections.
⁴⁴
Air raids on factories producing parts for U-boats, particularly batteries and accumulators, were particularly devastating.
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In addition, the time lost to bomb damage, absenteeism, or simply from workers taking shelter during air raids rose considerably in 1944.
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Anglo-American aircraft increasingly mined the Baltic to disrupt German shipping and submarine training. Dönitz frequently complained of this to Hitler, claiming that if Germany could not hold open the entrance to the Baltic, the U-boat war would come to naught.
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On several occasions the Skl noted that U-boat training areas, as well as several shipping lanes in the Baltic, had been closed because of the danger from mines.
⁴⁸

Many delays resulted from simple poor planning. The worst example was rushing the submarines into production without a prototype. Inexperience with sectional construction also caused serious problems. The tolerance for fitting sections together (initially plus or minus two millimeters for sections seven meters high and six meters wide) was rarely met, which meant that there was a good bit of shuffling sections around in hopes of finding a better match. Section ends often had to be stretched, shrunk, or patched to obtain a fit.
⁴⁹
Another problem was that the Type XXI submarines incorporated hydraulic power for all control systems and the periscope, antiaircraft armament, and torpedo hatches. But the Germans were relatively inexperienced with hydraulic design, and defects in the system led to chronic delays. Furthermore, construction of the submarines had already begun when snorkels were added to the design.
⁵⁰
On several occasions shortages of various components, such as batteries, periscopes, or electric motors, usually caused by Allied bombing, postponed production. Many sections arrived at the assembly yards with essential components missing. Moreover, at this stage of the war Germany lacked many high-quality materials required for these advanced submarines and had to substitute whatever was on hand.
⁵¹
Besides shortages of materials, the navy always lacked skilled workers.
⁵²
The Type XXIII submarines did not contain as much highly sophisticated equipment as the XXIs, which accounts
for their reaching operational status first. Further, although Hitler had assured Dönitz on 24 September 1943 and again on 26 February 1944 that he would support any measures to accelerate production of the new U-boats, in April 1944 he suddenly granted fighter production top priority. This confusion in armaments production also contributed to delays.
⁵³

Problems mounted in the final months. The Soviet capture of Danzig in March 1945 robbed Dönitz of one of three assembly sites for the new U-boats. The loss of Upper Silesia denied the navy that area’s industrial output. Chronic shortages of coal and electricity for shipyards, as well as fuel for the submarines themselves, impeded construction and training. A final reason for the Type XXIs’ delay was that each required a long period of trials to rectify teething problems, and their crews needed extensive training.
⁵⁴
The first Type XXI U-boats built required additional work after commissioning, about six weeks. Recognition of several problems that could be corrected during the construction process later reduced this time to about three weeks. Even proven submarine types normally required four months after commissioning before they were ready for action.
⁵⁵
The Germans obviously needed more time to work out the bugs in these new submarines and then train the crews. A variety of factors, therefore, contributed to failure of the Type XXI to reach the open seas before the war ended. Postwar studies conducted by the U.S. Navy concluded that had the Type XXIs become operational in large numbers, they could have posed a grave threat indeed.
⁵⁶

As it turned out, the Germans had devoted two years and enormous amounts of increasingly scarce raw materials to produce a weapon that did not yield a single Allied casualty. Vast numbers of skilled workers put in a colossal number of hours of labor to build these U-boats, which never fired a single torpedo at an enemy vessel. The construction of each submarine required an average of 252,500 man-hours, and approximately 40,000 production workers were involved in the Type XXI program.
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The new U-boat program tied up not only thousands of workers and 80 percent of the output of the nation’s entire electrical industry but enormous amounts of steel. The steel for the 170 Type XXI submarines ordered would have provided Guderian 5,100 additional tanks.
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The German war effort certainly would have benefited more from five thousand tanks than from Dönitz’s “miracle weapon.”

The Soviet Baltic Fleet

D
ÖNITZ
’
S GREATEST FEAR
was that the Soviet fleet would sail from Kronstadt into the Baltic and wreak havoc in U-boat testing and training areas. Until
the fall of 1944 he could point to the importance of shipping supplies to Finland and receiving imports from Sweden as equally vital reasons to maintain the blockade of the Soviet fleet within the Gulf of Finland. Then Finland surrendered and Sweden closed its ports to German vessels. Dönitz’s cries to keep Russian warships out of the Baltic, however, became no less shrill.

The Russians had begun to build up their fleet in the mid-1930s, because Stalin hoped to make the Soviet Union a world-class naval power. One area in which the Soviet Navy had an advantage over the Germans was its independent air arm, an asset Dönitz eagerly desired. Yet in the midst of the naval building program Stalin carried out his purges, which struck the Soviet Navy even more ruthlessly than the Red Army. In June 1941 Russia’s Baltic Fleet consisted of two old battleships, two modern cruisers, two antiquated cruisers, twenty-one destroyers, seventy submarines, and numerous smaller vessels.
⁵⁹
Raeder kept little of his naval strength in the Baltic in June 1941, because he expected the army to capture Russian naval bases quickly. The German Navy planned a defensive campaign in the Baltic, laying mine barrages to pin the Russian fleet within the Gulf of Finland until its bases had fallen.

At first everything proceeded according to plan. As Nazi troops neared Reval the Russians planned to withdraw to Kronstadt, forming four convoys with over one hundred warships and sixty transports and auxiliary vessels. The ships sailed from Reval but encountered trouble almost immediately. The convoys ran into German mines and came under repeated attack by aircraft. Exact losses are uncertain, but an estimated sixteen warships and thirty-five transports sank during the flight from Reval.
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By mid-September the Germans had severed Leningrad’s land contact with the Russian interior. Hitler feared the Soviet fleet would attempt to flee to neutral Sweden and he ordered German warships to take up blocking positions near the Åland Islands. The Luftwaffe then carried out a series of air raids on the Soviet fleet, damaging nearly all the heavy Soviet warships. By the end of the month the Skl had returned German warships to their home ports.
⁶¹
For nearly three years Russia’s Baltic Fleet remained blockaded near Leningrad. During this time its vessels served as floating artillery batteries, aiding in the defense of Leningrad and in January 1944 shelling German positions to support the offensive that finally lifted the siege. Soviet submarines broke into the Baltic in 1942, but they could not penetrate the mine barrages and submarine nets the Germans erected the following year.

Shortly after his appointment as the German Navy’s commander, Dönitz instructed the fleet to consider action to counter the possible emergence of
Soviet warships from the Gulf of Finland. Soviet minesweepers became more active there during the summer of 1943, increasing anxiety within the German Navy. As a precautionary measure the Skl ordered one thousand mines held in readiness in case the Soviet fleet forced a passage through existing mine barrages.
⁶²
In the fall of 1943 Dönitz faced a dilemma. Fearful of attracting Allied air raids to submarine bases and training areas, in September 1943 he forbade the transfer of the damaged battleship
Tirpitz
to Gdynia for repairs. To Dönitz, an operational battleship in no way justified the possible threat to the U-boat war, and Hitler supported Dönitz in this decision. Naval Group Command North/Fleet proposed the transfer of the heavy cruiser
Prinz Eugen
to Norway to compensate for the
Tirpitz’
s operational loss. Dönitz agreed to release
Prinz Eugen
from its training duties and prepare it for action, but not in Norway. He ordered the cruiser to remain in the Baltic, insisting that even a temporary disruption to the U-boat war must be avoided.
⁶³

At the beginning of 1944 the Soviets lifted the siege of Leningrad and pushed the Germans back to Narva. Dönitz’s panic resulting from these events has been examined previously. The Skl’s fear of the Soviet fleet’s breaking out from Kronstadt threatened to become reality. At this time the Germans gauged Soviet naval strength at one battleship, three cruisers, eleven destroyers, fifty motor torpedo boats, thirty-five submarines, and over one hundred small vessels.
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Compared to the British fleet this was not a terrifying force, but the Skl preferred not to have to scrape together units to meet this threat. The Second Task Force Dönitz had formed in January remained operational.

Finally, with Finland’s defection, the failure to capture Hogland, and Army Group North’s withdrawal from Estonia, the Skl’s fears were realized. Russia controlled the entire coast along the Gulf of Finland, and Soviet warships could enter the Baltic from Finnish ports or from Reval. Several naval commanders believed the Soviets would immediately send out submarines and motor torpedo boats. To make matters worse, German naval intelligence confirmed POW reports that the Soviets had increased their submarine strength in the Baltic by bringing additional submarines to Kronstadt via the Ladoga Canal and Volkhov River. Although the Germans did not expect the appearance of heavy surface vessels before the following spring, they could not rule this out. Germany’s Baltic task force made preparations for a fleet engagement.
⁶⁵

The belief in an imminent fleet engagement made the Germans reluctant to expose the Second Task Force to danger for any other purpose. Admiral Burchardi maintained it was too risky to support Army Group North’s withdrawal in the Riga area, insisting that the task force remain clear for action
against the Soviet fleet; similarly, Meisel informed Guderian in December 1944 that the navy had to preserve its cruisers and destroyers for an anticipated clash with the Russian fleet. Kummetz declared his intention to send the Second Task Force into action as soon as vessels the size of a destroyer or larger appeared.
⁶⁶
In mid-February 1945 Soviet motor torpedo boats attacked a Courland convoy. Dönitz’s reaction to this relatively minor incident demonstrates his fear that disaster loomed. He considered transferring Germany’s entire motor-torpedo-boat force from Holland and Norway to the Baltic. Other officers vigorously protested this proposal, and cooler heads pointed out that there would be problems finding bases for these vessels and that the withdrawal of all such vessels from the West would free considerable enemy forces. Meisel suggested that Dönitz transfer only two of the six flotillas currently stationed in the West. The following day Kummetz reported that Soviet aircraft were his greatest concern and assured the Skl that his forces could deal with Russian surface vessels in the area. Dönitz calmed down and accepted Meisel’s proposal.
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Nonetheless, Dönitz still wanted to wipe out any Soviet surface vessel that endangered the revival of the U-boat war. He advocated a raid by German destroyers or torpedo boats against Soviet bases in Lithuania, but the Skl warned that the danger from German mines in the area was too great.
⁶⁸
The Skl recalled the disasters that had befallen the warships that had attempted to reinforce German minefields the previous year. Dönitz did not.