Chapter XIV
U-boat operations in the Indian Ocean and the Far East

  1. Organization and background.
    1. German interest in these operations and lack of Japanese cooperation.
    2. The development of U-base Penang. German difficulties.
    3. Decline of the German effort. Japanese press for cooperation.

  2. Blockade running submarines.
    1. Plans and preparations.
    2. Achievement.
    3. Japanese U-boats.
    4. Satsuki U-boats given to Japan.
    5. Ex-Italian Akira U-boats.
    6. German U-boats.
    7. Summary.

  3. U-boat chronology.
    1. First German U-boat operations in the Indian Ocean area, October to December 1942.
    2. Group Seehund operations, February to March 1943.
    3. The exchange of Subhas Chandra Bose.
    4. Gift of U-boats to the Emperor of Japan.
    5. Independent operations, May to August 1943.
    6. The Monsun venture.
    7. Operation of Monsun submarines on outward voyage.
    8. Second cruise of the Monsun submarines - Far East to Germany.
    9. The sinking of the Charlotte Schliemann and the Brake.



  1. Organization and background.

    1. German interest in these operations and lack of Japanese cooperation.

      Although German and Japanese Naval Attaché traffic for 1942 is scarce, it appears that as early as August 1942, the Germans had begun negotiations for the use of a base on the Malay Peninsula where they could supply and repair U-boats operating in the Indian Ocean.

      There were many reasons for the decision to undertake extensive operations in the Indian Ocean. In 1942 Germany appeared to be winning the Battle of the Atlantic and could afford to divert part of the U-boat fleet to new fertile fields. Allied anti-submarine measures around South Africa were primitive as compared to those in the Atlantic, and with the tightening of the anti-submarine defenses off the South American coast, the Freetown area and in other areas previously considered "soft spots," the planning of operations in waters less well patrolled was considered urgent.

      As Germany's war situation deteriorated new reasons for Indian Ocean operations appeared. The Germans had expected to take the Suez Canal and to sweep through the Caucasus to meet the Japanese in India. But in the latter part of 1942, the German drive in North Africa was halted, and Rommel was forced into full retreat. The sinking of Allied supply ships became even more important, and the Persian Gulf and Red Sea supply routes to Russia and the British forces in Egypt became priority targets. Even after the Germans had been chased out of Africa, and the Mediterranean was opened to Allied use, the Indian Ocean was considered important by the Germans. With the reverse in North Africa came also the defeat of the U-boats in the Battle of the Atlantic in the spring of 1943. The U-boat packs were withdrawn from the North Atlantic and large numbers of unemployed submarines were sent to patrol distant areas where shipping was plentiful and anti-submarine defenses less dangerous. Until the U-boat Command could devise new weapons and defenses to meet Allied antisubmarine


      tactics some shipping successes were demanded to support morale and propaganda warfare.

      A Far Eastern base of operations was clearly required if German plans were to reach fruition. A base required supplies, and the smashing of surface blockade runner traffic threw the burden on operational U-boats, a burden made back-breaking by the necessity for using submarines to carry cargo vitally needed by Germany. This phase of U-boat operation will be discussed separately in section 2 of this Chapter.

      Cooperation between the Germans and Japanese in the planning and execution of this program was thoroughly unsatisfactory and results achieved by the Germans were brought about in great parts in spite of, rather by reason of, joint negotiations.

      When it had become clear that the Germans and Japanese armies would not meet in India, the Japanese lost interest in plans for a German base in the Far East. Japanese apathy continued until 1944. They seemed to believe that the tonnage sunk in the Indian Ocean would be of greater benefit to the Germans than to themselves, and that German U-boats would be using supplies which they could well use themselves. Furthermore, German exploitation of Japanese influenced waters was distasteful to them. Whether they did not wish to be too closely associated with an ally whose changing fortunes of war were likely to make her a burden to the Japanese, or whether it was merely their innate and traditional distrust of foreigners, it was evident that they were not enthusiastic.

      Germany persisted in its attempts to build up the Far Eastern flotilla until the Allied threat to the homeland became too great. By that time the Japanese had decided that it would be well to have a large submarine fleet to help in their fight. It was then too late. Each nation attempted to use the other for its own advantage. Each in its turn had been rebuffed.

    1. The development of U-base Penang. German difficulties.

      As mentioned above, negotiations for a German base in Malaya had begun in 1942. The German-Japanese Naval Communications Agreement had been under discussion since early 1942, and by August of that year the joint correspondence had reached the phase of assigning spheres of operations. The message from the German Naval Attaché in


      Tokyo referring to this question is interesting, not only because it is the earliest evidence that negotiations were underway, but also because the dissensions and misunderstandings which characterized all succeeding attempts at collaboration are here clearly shown to have hindered the planning at its inception. The German Naval Attaché said:

      "Interpreter was given to understand that (Germany's), penetrating into (Japan's) operation area is not favored. Propose (that question) be brought up again . . ." (Seahorse #443, 27 August 1942)

      The final assignment of spheres of operation was not made until September 1943, German U-boats being restricted to the area west of 70°E. As it will appear later this agreement was never obeyed and probably was discarded with the tacit consent of both parties, Japan having become increasingly unable to conduct offensive operations in the Indian Ocean.

      In September 1944, the choice of a person "to look after the Naval Attaché's affairs and for supervising the south area" (Seahorse #87, 4 September 1942) was under discussion, and Captain Vermehren was chosen, being more acceptable to the Japanese than other candidates mentioned. Thereafter Vermehren retained general control of all Far Eastern activities, although direct control of the Penang-Batavia area was maintained by the Commander Southern Area. The site of the main submarine base was chosen in December, Penang being favored by the Japanese because of its suitable naval equipment. The fact that the Japanese COMSUBs was also located there may have been a deciding factor, for possibly the Japanese wished to keep a high ranking eye on the situation. Singapore was named as the port for major repairs and docking.

      The first German U-boat to dock at Penang, in July 1943, was U-511. Schneewind, its commander, took temporary charge of the base while his submarine was presented to Japan. The first regular commander was Dommes, who arrived in August 1943, in U-118.

      Innumerable difficulties were placed in the way of the Germans. Services and supplies were of poor quality; bases were never well equipped with personnel or supplies; and it was reported that "everything must be begged in protracted discussions from Japanese stations." (Seahorse, PPA 60, 20


      October 1944) U-boat and blockade runner crews had to load, unload and repair their own vessels, while the few Japanese workers seemed to spend their time spying on new German equipment. No torpedo house was available, and the U-boats were forced to stow torpedoes in a building used by the Japanese. U-boats had to go to Japan proper to change worn out batteries.

      The greatest difficulties were encountered with regard to Japanese fuel and anti-submarine patrol in the straits leading to the bases. There was a good bit of duplicity on the part of the Japanese in representing the quality of the fuel and lubricating oil with which they supplied the Germans. They affably agreed to provide oil of the quality required by German submarines, but unofficially spoke of the fact that the oil would not come up to the standards. Samples of proper quality were provided, but when quantities were delivered the promises and samples were found to be merely promises and samples. Diesel oil was particularly unsatisfactory, and caused so much damage to U-boat diesels that the Germans were finally forced to conduct their own purification experiments. These seem to have been fairly successful.

      Even in 1943, when the Japanese would seem to have been most able to furnish a sufficient number of well equipped anti-submarine patrol vessels for escort purposes, their activity in this respect was so weak and resulted in the loss of, or damage to, so many submarines that the Germans were forced to protest strongly. When no improvement was forthcoming they found it necessary to enforce radio silence in the vicinity of the bases in order, as they thought, to deceive the ever lurking Allied submarines. In fact, timely and accurate radio intelligence enabled the Allies to deploy their submarines with a view to economical destruction of enemy craft. Only after Japan was faced with the threat of disrupted supply lines, after Germany began to lose interest in Far Eastern adventures, were steps taken to increase and improve patrol vessels.

      Not even personnel matters were removed from the no-man's land of quarrels. The Japanese COMSUB in the Southern Area was an Admiral. The German commander was a Lieutenant Commander, and was therefore unable to deal on an equal footing with the Japanese. Although Vermehren in Tokyo was a Captain, Japanese organization made it impossible for him to deal effectively with the Japanese staff in Tokyo, which automatically referred all questions to the local office.


      In order to improve the situation Naval Attaché Wenneker suggested that a Captain or Admiral be made Commander Southern Area. This suggestion was not followed, although Berlin did promote Dommes, the Commander, to the rank of Commander.

      Even more disastrous difficulties confronted U-base Penang. The first supplies sent to the new base were carried by 11 U-boats which left Biscay in June and July 1943. By the end of August, five had been sunk in the Atlantic, partly as a result of radio intelligence fore knowledge of rendezvous points, and one had been forced to return to port. This misfortune also deprived Penang of the man slated to become its first Commander, Kuppisch. It was necessary to relieve Dommes of the command of U-178 to become Commander Penang.

      The whole, history of the bases in the Far East is a history of improvisations to meet problems posed by Allied interference with German routine. Two U-boats, slated to carry cargo between Germany and Penang, were pressed into the cargo run between the south and Japan and finally immobilized by decrepitude in Kobe. The problem of sending supplies from Germany was never solved. Plans to use old Italian submarines failed; a program of cargo boat construction was canceled; operational U-boats were forced to carry cargo and consequently lost much of their offensive efficiency. In short, when it became clear in 1944 that U-boats were more needed in the Atlantic, there was no great urge to continue building up the Far Eastern fleet.

    1. Decline of the German effort. Japanese press for cooperation.

      In October 1944, it became apparent that Penang was no longer a suitable base. Allied submarines prowled the Malacca Straits constantly and often lay just outside Penang harbor, so inept were Japanese anti-submarine defenses. The concentration of the British fleet at Ceylon, the Burma campaign, and attacks on the Nicobar Islands also endangered the base. Further, the Germans were convinced that part of their troubles were caused by the British D/F stations which concentrated on Penang. Even the Japanese were dissatisfied and the Japanese COMSUB was planning to shift his base.

      Accordingly, on 25 October orders were issued making


      Batavia the main homing port, Penang being used only in urgent cases. On 15 November this order was expanded, Surabaya becoming a major repair base in addition to Singapore. For all practical purposes Penang was evacuated, the last U-boat (U-843, Herwartz) leaving before 1 December. On 1 January 1945, Dommes was promoted from Commander Penang to Commander Southern Area in recognition of his increased duties.

      No great problems, other than those concerned with transferring supplies and personnel, were involved in the change of bases. Surface blockade runners had used both Batavia and Surabaya, and an organization was already in existence. There had also been German seaplane bases at both ports. The change was not destined however, to improve Germany's Far Eastern fortunes.

      German desires and intentions concerning the Far Eastern venture are nowhere more in evidence than in the statistics showing the number of U-boats sent out. In 1943, eight submarines were sent to the Far East. From 1 January 1944 until the invasion of France on 6 June, 15 submarines commenced the trip. During the remainder of the year only five were sent, none of them putting out after August. In 1945, two departed Norway, and at the time of the surrender there were no plans to send more. Indeed, those based in the Far East were sure to be sent home.

      The disintegration of the German effort in the Far East was made even more apparent by the growth of Japan's interest in strengthening that effort. Formerly an unwelcome burden, the German U-boats became weapons to be desired. In September 1944, began a series of requests for more submarines for joint operations in the Pacific. Every possible assistance was promised if this were brought about, and work was actually started on the long promised anti-submarine defenses. The Japanese put forward many reasons why the transfer of more and more U-boats would be of benefit to both countries. The loss of French bases had forced the submarines to Norwegian and German waters where they would be particularly vulnerable to Allied aircraft. Since Allied radar had sharply curtailed successes in European waters, it would be far better to operate in the Pacific where Allied anti-submarine measures were less advanced and attack opportunities were good. It was further argued that such operations would stimulate German morale, which would need a stimulus if the


      fuel shortage in Europe forced many U-boats to remain idle.

      But Germany now showed as little enthusiasm for this plan as Japan had shown two years before. Japan was thanked politely and informed that an intensification of Far Eastern operations was to be desired; but there was a limit to what could be done, since the German war situation demanded full use of the U-boat fleet. Grand Admiral Dönitz said that the old type submarines, which Japan claimed were too weak defensively to operate in the Atlantic, had on the contrary almost never been discovered by the Allies since the advent of the schnorchel. With schnorchel they were equal to the most difficult patrols off the English coast. However, something might be done if the Japanese Navy would show its good-will by making better arrangement for anti-submarine measures in the entrances to the southern bases.

      Japanese pressure was not relaxed, and being aware of German misgivings, they proposed in September 1944, the establishment of a combined command under Admiral Nomura, a man well thought of by the Germans when he was the special representative of the Japanese Navy in Berlin. Nothing came of this scheme, however.

      Germany made only two tangible efforts to cooperate. In December 1944, one U-boat operated off southern Australia with moderate success. In January 1945, it was announced that a German Vice Admiral would reveal a concrete plan for carrying out operations of German submarines in the Philippines area after consultation with the Japanese. One U-boat left Batavia enroute to the Philippines late in April, but is believed to have been sunk by a U.S. submarine when only two days out of port.

      The last Japanese attempt to lure more U-boats to the East was made in April 1945. Dönitz' excuses were: defense of the homeland and lack of fuel for the long trip. Japan's neat circumvention of the latter excuse by offering to refuel any U-boats south of Capetown came too late, for the next news from Germany was surrender. Dommes, Commander Southern Area, had promised on 29 April to continue operations with the Japanese; and on 7 May Berlin ordered Dommes and Attaché Wenneker to turn over to the Japanese all but one U-boat, that one to carry selected personnel back to Germany. Japan, however, seems not to have depended on these formalities. As of 1 June 1945, it appears that the six remaining German U-boats in Far Eastern ports as well as all facilities were seized as


      early as 7 May.

  1. Blockade running submarines.

    1. Plans and preparations.

      Germany's relatively acute shortage of rubber, tin, tungsten and molybdenum forced the nation to attach great importance to blockade running. Surface vessels were used until January 1944, but the rate of attrition made it clear to the Axis almost a year earlier that some other means of transportation must be found to supplement, if not to replace, those ships. The German solution involved transport submarines. Fortunately, from the Axis point of view, conditions seemed favorable for the speedy development of such a system. Germany had been planning for some time to expand its area of operations to the Indian Ocean and in 1942 had arranged for a supply base at Penang. In addition, the long cruise between Europe and the Far East had been successfully completed by German and Japanese U-boats by early 1943, so that the scheme was not wholly untested. It is also significant that during 1943 the U-boat began to lose its effectiveness as an offensive weapon in the Atlantic Ocean. There were, therefore, more submarines available to serve as undersea freighters, at least until the German High Command could devise new weapons to meet Allied anti-submarine warfare.

      In April 1943 the Atlantic Section became aware of the elaborate plans for submarine blockade running through a report from Ambassador Oshima dated 31 March 1943. This mentioned a plan to convert some old Mediterranean U-boats to carry rubber and other materials. No German submarines used as cargo carriers fit such a description, and probably the reference was to nine Italian Akira submarines, first mentioned by name in April 1943. The Germans evidently desired to put their program into immediate operation; and, pending readiness of their own submarines, they took over nine Italian boats for use beginning in May. General outlines of the plan were revealed in traffic read during May, but complete details were lacking until after the surrender of Italy. The U-boats (cover names: Akira and Mercator) ranged around 1,000 tons, and the plan was to have them make two round trips yearly, carrying 150 tons of cargo per trip.

      In the meantime Germany was to build 30 transport


      submarines which eventually were to handle the bulk of the traffic. These were to be ready for operation late in 1944, but plans for their construction were canceled early in 1944, because they were "unsuited to the present enemy situation." (Seahorse PPB 68, 17 January 1944)

    1. Achievement.

      Whether by accident or intent, the burden of carrying out this supply program fell almost entirely on German supply program fell almost entirely on German submarines sent to operate in the Indian Ocean. The disastrous failure of the Akira plan, the cancellation of plans for 30 transport boats, and the poor record of Japanese U-boat transport made this inevitable. During 1943, most of the submarines used were 750 tonners which had previously operated in the Atlantic. During 1944, however, most of the U-boats sent out were of the 1200 ton class, and it is clear that this class was to have been standard unless and until a more efficient new type was developed. At one time it had been planned to use high speed type XXI U-boats in this traffic, but this plan was dropped when the situation in the German homeland became desperate.

      The most important cargoes to be brought from the Far East have been already mentioned. In return, Germany shipped lead, mercury, aluminum and special steels in bulk. Of far more strategic importance, however, were the secret offensive and defensive weapons and special devices which were sent to Japan. The list includes acoustic torpedoes, radar gear and ENIGMA cipher machines. The plan to transport materials to Japan was never carried out fully, however, because the maintenance of the U-bases at Penang, Batavia, etc., made it necessary to use almost all available cargo space for supplies to these bases.

      Submarines were also used to transport key personnel. Vice Admiral Nomura (Chief of the Japanese Army-Navy Military Inspection Group which toured Europe in 1941), Rear Admiral Koshima, German Ambassador to Nanking, Woermann, and Subhas Chandra Bose were transported by this means, as were many civilian and military technicians. The last U-boat to leave Germany for the Far East carried the newly appointed Air Attaché to Tokyo, General Kessler. His trip was interrupted in


      May 1945, and he landed at Portsmouth, New Hampshire.1 Fortunately - and partly because of the nature of the subject - current information was available during almost all of the cruises, and experience gained during the period of surface blockade running enabled the Atlantic Section to cover this traffic without additional difficulties. It is interesting to note that of the 56 cargo carrying submarines sailing to or from the Far East since 1942, 29 were sunk by Allied action while outbound; one was interned in the U.S. shortly after sailing for Asia; and three were forced to cancel their trips. Of the 23 that managed to complete half of the round trip only five managed to return to the homeland; nine were sunk while returning or operating in the Far East; one was given to Japan by Germany; six German and ex-Italian U-boats were seized by the Japanese; and two were interned by the Allies while returning to Germany.

    1. Japanese U-boats.

      Four Japanese submarines - all approximately 2,600 tons - sailed for Europe. Only one completed the round trip without mishap. Two returned to the Far East but were sunk before the voyage ended. The fourth, carrying about 270 tons of tin, rubber, tungsten, molybdenum, and gold, as well as at least 14 technicians and diplomatic officials, was sunk in the Atlantic before reaching Europe.

      Japanese submarines, therefore, brought only about 250 tons of rubber, tungsten and gold to Europe, and carried only some machinery back to Japan - so far as is known. Of approximately 100 passengers carried, about 90 reached their destination (including an entire crew for a submarine given to Japan by Germany).

    2. Satsuki U-boats given to Japan.

      Two 750 ton German U-boats (Satsuki) were given to Japan. One cruised safely to Japan manned by a German crew and carrying two important passengers. What its cargo was, if any, is not know. The other left Germany with a Japanese crew. It was equipped with all the latest U-boat gear (around


      March 1944) and carried about 85 tons of cargo, probably lead and mercury, as well as about 12 passengers. It was sunk enroute.

    1. Ex-Italian Akira U-boats.

      Nine Italian submarines (Akira), ranging from 950 to 1,300 tons, were converted to transports in 1943. The plan to carry 150 tons on two yearly round trips was a complete failure. One boat remained in Bordeaux, and was finally destroyed in August 1944. Five left Europe but were sunk before reaching the Far East. Three reached Singapore in 1943 with a cargo of aluminum, ammunition, machinery and medicine. The main purpose of the voyages - to return to Europe with vital cargoes - was not carried out, and the Germans were forced to abandon their plan. One of the three was sunk off Penang; and the last two, after vain attempts to return, were given the job of carrying cargo between Singapore and Japan, and of refueling other submarines in the Far East. They were presumably seized by the Japanese in May 1945.

      At most, Japan received 450 tons of aluminum and assorted medicine and machinery on the Akira submarines. Germany gained experience and perhaps good will.

    2. German U-boats.

      Forty-one German U-boats attempted the cruise to the Far East. Two were forced to cancel their trips, one was interned in the U.S. after Germany surrendered, and twenty-two were sunk while outbound. Only sixteen, or 39%, reached the Far East. Of this number four completed the round trip, six were sunk while operating in Asiatic waters or returning, four were seized by the Japanese, and two were taken by the Allies while attempting to return to Germany.

      Two 1,000 ton, type VIIf submarines were sent to Penang early in 1944, with torpedo stocks for that base. Each carried about 25 torpedoes, but information on additional cargo is not available. It is probable that total cargo capacity was about 150 tons. One of these U-boats was sunk while still in the Atlantic. The second reached Penang but was sunk in the Atlantic while returning with a cargo of tungsten.

      Three submarines of the second special class were sent out. These were type Xb U-boats, 1,600 ton mine laying and


      refueling craft. The first such submarine was sunk in mid-Atlantic in June 1944; but the second was able to reach Penang, after conducting a refueling operation enroute, landing 8,552 bars of aluminum, 868 bars of lead, 990 bottles of mercury and 61-boxes of crude glass for the Japanese. It was seized in Batavia in May 1945. The third of this type left Norway in April 1945, and was forced by the surrender of Germany to put into Portsmouth with a valuable cargo of documents and General Kessler, new German Air Attaché to Tokyo.

      The remaining submarines were the so-called Monsun boats, operational U-boats, forced by necessity to act as cargo carriers even though the dual role lowered their effectiveness in carrying out either task.

      During 1943, 750 ton type IXc boats were most commonly used. They were able to carry about 110 tons of cargo and to operate enroute if refueled. Fourteen of this type left Europe between June 1943 and March 1944, carrying supplies to Penang. One was forced to put back into port; six were sunk while outbound to or returning from the Far East. Of the seven which managed to reach port unscathed, three were sunk while operating in the Far East. Only one of the remaining four is known to have been completely successful in his round trip, bringing 29 tons of tungsten and about 80 tons of tin, quinine, opium and vitamins to Germany. Still another returned to Norway but was sunk enroute Kiel. The other two returned too late, and were seized by the British.

      Late in 1943 it was obvious that 750 ton boats were not sufficiently effective, their cargo capacity and offensive abilities being too greatly weakened. The inability to refuel without Allied interference was one important reason for this, and the actual cargo record bears out this belief. In two years, the 750 ton submarines delivered only about 110 tons of cargo to Germany, and carried no more than 750 tons of lead, mercury, etc. to Japan.

      Accordingly, the new 1,200 ton type IXd U-boats were used exclusively after March 1944. This class was able to carry a cargo of 200-250 tons and to operate enroute without refueling. Only about 110 tons were carried on the outbound cruise, additional fuel and weapons for patrolling probably being responsible for the smaller cargo. Most of the cargo carried to the Far East consisted of lead, mercury, aluminum, platinum, special steels and optical glass, as well as supplies for Penang. More important, however, was the relatively light


      weight cargo of secret weapons, special devices and important documents. It is also probable that passengers were carried on most of the trips.

      About 50% of the 200-250 ton return cargo was rubber. Approximately 60 tons of tin were carried in the keel, with some 40 tons of tungsten and molybdenum and 10 tons of vitamin concentrates, bismuth, iodine, selenium and quartz crystals completing the cargo.

      Twenty-two type IXd submarines attempted the trip to Asia. One was forced by aircraft damage to cancel its trip while still in the Baltic. Only three completed round trips (and one of these was sunk while outbound for the second time). These trips netted Germany about 188 tons of tin, 83 tons of rubber, and 67 tons of tungsten. Fifteen of the boats went down between ports. The last three were preparing to return to Germany when they were seized by Japan in May 1945.

      Thus, in spite of the greater efficiency of these U-boats, they failed to remedy Germany's desperate supply shortage and failed also to keep the Asiatic bases properly supplied. Only about 400 tons of cargo were carried to Germany on the 1,200 ton submarines, while the Japanese, although faring better, received only approximately 600 tons of special metals, finished products and secret devices.

    1. Summary.

      To summarize: the U-boat blockade running system was in operations for about two years. During that time Germany received only about 700 tons of raw materials, some gold (to bolster Japanese credit) and a few blueprints and weapons. Japan received some 1800 tons of metal and secret devices. The utter and ignominious failure of this plan is nowhere more clearly portrayed than in this one comparison: one surface blockade runner, the Wesserland, was carrying about 10,000 tons of cargo to Germany when it was sunk in January 1944.

      It was clear to the Germans as early as September 1944, that the plan was not a success. Vice Admiral Abe, speaking on 15 October 1943, stated that Germany's minimum tungsten requirement by the end of that year was 3,000 tons but that transportation had been arranged for no more than 700 tons. By 1 May 1945, no more than 300 tons had been received. And while a few such trips were necessary for vital


      commodities and for morale purposes, the will to succeed in the Far Eastern adventure gradually died.

      Submarine blockade runners did not solve Germany's supply problem, but they have perhaps created a new problem for the Allies in the Pacific. The secret weapons, special devices and cipher equipment transferred to Japan may noticeably increase the fighting potential of that nation. In spite of themselves the Japanese have benefited from the program.

  1. U-boat chronology.

    The following section presents an outline of some of the war cruises in the Far East. Only highlights of the more important cruises have been given.

    1. First German U-boat operations in the Indian Ocean area, October to December 1942.

      In the month preceding the invasion of North Africa in November 1942, what were apparently the first German U-boats to operate in this area appeared off Capetown. Perhaps a half dozen reached this area around the middle of October and in November passed to the eastward and operated in the southern part of the Indian Ocean as far north as Lourenco Marques. The names of but four come to light from traffic: Lüth (U-181), Witte (U-159), Ibbeken (U-178), and Gysae (U-177). Little traffic was read for this period, and it is not possible to state how many ships were claimed sunk by this group. Suffice it to say that shipping losses in the Indian Ocean began to rise. All the submarines known to have operated returned safely to port.

    2. Group Seehund operations, February to March 1943.

      The operational campaign was resumed in the first week of February 1943, when group Seehund, consisting of Lassen (U-160), Wibe (U-516), Clausen (U-182), Würdemann (U-506), and Witte II (U-519), arrived of southern Africa. Capetown became the main area of concentration, with two submarines going north along the eastern coast of Africa as far as


      Inhambane. Having been refueled before beginning operations, the U-boats were able to stay in their attack areas until the first week in April. As far as can be learned from traffic, 22 ships, of about 148,000 GRT, were claimed sunk as a result of this operation. The submarine commanders were all impressed with shore and aircraft radar, which often forced them to submerge and prevented them from approaching closely to the main ports and to ships and convoys. An important part of this group's work seems to have been the supplying of information to Command concerning convoy gathering points and independent shipping routes.

    1. The exchange of Subhas Chandra Bose.

      The first Indian Ocean cruise not undertaken primarily for offensive purposes involved the transportation of Subhas Chandra Bose, former president of the All-India Congress and an agitator of pro-Japanese persuasion, from Germany to Japan so as to enable him to enter India at the heels of the victorious Japanese army. Bose was embarked on the U-180 (Musenberg) and left Germany on 9 February 1943. During the cruise information on Indian activities was passed to Bose by means of special "Nelke" messages. These messages provided the first clue to the existence and then the identity of the passenger. They were also of great value in analyzing the workings of the Free India Movement and in identifying the participants.

      Undismayed by the presence of such "distinguished" supercargo, Musenberg attempted offensive action during the outbound cruise, managing to sink one ship.

      Bose was transferred to a Japanese submarine at a rendezvous in the Indian Ocean late in April. In addition, German torpedoes and mail were exchanged for Japanese inventions, apparatus, gold, quinine, and Japanese naval technical personnel. After unproductive patrolling along the southeast African coast, Musenberg returned to the Bay of Biscay. In order to prove to the Japanese the comparative safety of U-boat transport operations, Musenberg and his crew were instructed to "dispel the fears already entertained by the Japanese command in regard to the Biscay cruise . . .by appropriate attitude and conduct of your whole crew . . .under no circumstances is the attention of the Japanese to be drawn to any special endangerment of the Bay of Biscay." (Shark 1304/24 June 1943) Nevertheless, the Japanese attention was


      forcibly called to this condition by Allied aircraft which attacked U-180 the day before it reached port, 1 July 1943. A record of this trip, kept by the Weapons Officer on the U-180, was among the documents taken from U-505, whose commander, Lange, was that Weapons Officer.

    1. Gift of U-boats to the Emperor of Japan.

      Part of the German attempt to improve relations with Japan involved the gift of two U-boats to Hirohito. This gesture of goodwill was to be completed by the presentation of two Japanese submarines to Germany. Japan had requested two large U-boats, 1100 and 1350 tons, but only 750 tonners were sent. The Germans, therefore, were in no position to complain when the Japanese gift turned out to be three old ex-Italian boats which the Germans themselves had repaired.

      As usual, misunderstanding plagued the exchange. The German navy demanded payment, evidently not having been informed that the submarines were gifts, and the personal intervention of Hitler was required to straighten matters out.

      The first German submarine left Europe in April 1943, under the command of Schneewind (U-511). On board were Admiral Nomura, former special naval representative in Germany, and Woermann, German Ambassador to Nanking. As was the case with Musenberg, Schneewind did not hesitate to engage in operations along the way, with no more success than the former.

      On 14 July 1943, U-511 reached Penang, the first German U-boat to touch at a Far Eastern port. The U-boat was officially turned over to the Japanese navy at Kobe on 16 September. Schneewind became Senior Officer U-Base Penang.

      The Japanese officers and crews to man the second gift submarine were brought from Japan on the Japanese submarine I-8 in the fall of 1943. After several months of training and study, they took over U-1224, and on 30 March 1944, departed Kiel for Japan. As an instrument of German goodwill, U-1224 was a failure. The course and approximately daily positions of the submarine were known by radio intelligence and enabled TG 22.2 to meet U-1224 on course at about 18°E - 33°W and to sink it, possibly on 13 May 1944.


    1. Independent operations, May to August 1943.

      During the summer of 1943, seven U-boats operated independently in the Indian Ocean: Kentrat (U-196), Hartmann (U-198), Bucholz (U-195), Lüth (U-181), Gysae (U-177), Dommes (U-178) and Bartels (U-197). They were concentrated, mainly around Durban, Lourenco Marques, south of Madagascar and off Mozambique. Capetown and Mauritius were also patrolled. According to claims reported in their messages, operations were highly successful. Thirty-six ships, of about 235,000 GRT, were claimed sunk, nine of them by Lüth, who was awarded the highest German decoration for his success.

      On 22 June all of these U-boats were refueled by the Charlotte Schliemann south of Madagascar, the first refueling of its kind in the Indian Ocean. Five of the seven returned to Europe. Bartels was sunk while operating off Madagascar, and Dommes was ordered to make Penang his homing port and operational base. U-178 was, therefore, the first U-boat assigned to U-base Penang.

    2. The Monsun venture.

      The operational culmination of negotiations begun in 1942 for the use of German U-boats in the Far East came in mid-1943, when the Monsun boats left France. The role of these submarines as cargo carriers has already been discussed; in addition, they were also expected to patrol assigned attack areas before continuing on to Penang. This scheme was said by prisoners of war to have been the idea of Lieutenant Kuppisch, who commanded a Monsun boat, U-847, and, according to prisoner of war information, was destined to be the first Commander U-Base Penang.

      Pich (U-168) and Lüdden (U-188), the first Monsun boats to sail, left France about 30 June 1943. Tillesmann (U-516), Würdemann (U-506), Auffermann (U-514), Hennig (U-533), Schäfer (U-183), Junker (U-532) and Witte (U-509) left between 5 and 8 July. Pietzech (U-532) also left at this time, but was forced back to port with engine trouble and did not leave until 16 August. Kuppish (U-847) left the end of July. By the end of August, of the eleven Monsun boats which had sailed from France, five had been sunk in the Middle Atlantic, and one had been forced to drop out of the operation. Behind the disaster lay one of the most important reasons


      for the eventual replacement of the 750 ton U-boats by the 1,200 ton U-boats in Monsun traffic. In order to make the long trip and to operate on the way it was necessary to refuel 750 ton submarines, and the mortality rate at refueling rendezvous' was staggering.

      In the instant case the rendezvous area, 27°N - 37°W, was infested as never before with U.S. Navy EVE's. The Core, Santee, Bogue and Card were in the area, and the Core and Santee, escorting UGS convoys, were detached on about 10 July 1943, to operate against submarines in the vicinity.

      The appearances of the EVE's at the scene of the rendezvous was not by chance. The following information from radio intelligence sources was available. Several U-boats were known to be outbound and were thought to be headed for the Far East. Metz (0-487), known to be a supply U-boat, was ordered to head for the area of 36°N - 30°W. It was customary for submarines to be refueled before beginning a long cruise, and radio intelligence experience had proved that the area south-southwest of the Azores was a popular rendezvous area. The bits of information fell into place, and the approximate date and position of a large refueling operation could be determined, in spite of the fact that at the time traffic was not being read currently. The original German plan had been for Vowe (0-462) to fuel the Monsun submarines. He, however, when only a few days out of port, was forced back by aircraft damages. Metz was then the only regular refueler available, and since he did not have sufficient supplies, Pommer-Esche (U-160) was ordered to turn over his provisions and extra fuel as a supplement. Unknown to COMSUBs, Pommer-Esche had been sunk earlier. Metz arrived at the rendezvous by 13 July and was promptly sunk by Core aircraft. By 18 July, COMSUBs realized that Metz had been sunk and ordered direct fueling from Pommer-Esche, still believed to be active, and Piening (U-155), an outbound operational U-boat. When COMSUBs became aware of the sinking of the former, Tillessen, a Monsun boat, was substituted. He fueled Schäfer, Pich, Hennig, Junker and Lüdden, the only remaining Monsun submarines, Witte having been sunk by aircraft from the Santee, and Aufferman and Würdemann while enroute to the rendezvous.

      The sinking of a refueler was always important, but this U.S. Navy action had more far reaching consequences. The whole Monsun plan required revision. Having received so little


      fuel from the make-shift provisioners, the U-boats had to break off operations in the Indian Ocean and refuel for the second time, from a surface tanker sent out from the Far East. Valuable supplies for Penang were lost or carried back to France, and efforts had to be concentrated on the Penang supply problem.

      With the sinking of Metz is connected to loss of another important Monsun boat, Kuppisch (U-847). Three other active refuelers besides Metz had been sunk in July 1943, and Kuppisch was one of the several operational U-boats forced to act as refuelers pro-tem. On his way to the Far East in July, he was ordered to refuel six submarines. While standing by in the rendezvous area, (which radio intelligence had spotted several days in advance) he was attacked by Card aircraft and sunk on about 27 August. Not only the submarine but the man possibly destined to be the first Commander Penang was lost.

    1. Operations of Monsun submarines on outward voyage.

      Five U-boats finally reached the Indian Ocean for operations: Hennig, Schäfer, Pich, Junker, and Lüdden. They were fueled by the Brake on 8 September, southeast of Madagascar, before cruising to their attack area. Each commander was allowed to use his own judgment to some extent in choosing his attack area, and from September to November 1943, the northern Indian Ocean was well patrolled. The main areas of concentration were the Gulf of Aden, Gulf of Oman, and the Laccadive-Maldive Islands. Operations were also conducted off Mombassa, Calcutta and Bombay.

      The operations on which so much time, fuel and work had been expanded were extremely unproductive. Only three ships, of about 19,000 GRT, were claimed sunk, and the loss of Hennig on 16 October reduced the Monsun fleet to four submarines. A note of desperation may be heard in COMSUBs message to Schäfer: "This undertaking ought to lead to something." (Shark 1246/12 October 1943) The four remaining Monsun boats reached Penang by November 1943.


    1. Second cruise of the Monsun submarines - Far East to Germany.

      The return cruise of the Monsun submarines was even more ill-fated than the first. It was a most important operation, and the submarines were ready to sail only after two months of intensive preparations. They had been stripped to the hull in order to carry the greatest possible cargo load, torpedoes and armament being sacrificed to this end. Interim operations in the Indian Ocean were planned, but they were incidental to the main objective.

      Schneewind, who took over U-183 after Schäfer's death in Penang, Pich (U-168), Junker (U-532), Lüdden (U-188), and Spahr, who replaced Dommes in U-178, left Penang at intervals from 29 November 1943 to 1 February 1944. During January and February, patrols were maintained from Ceylon to the Gulf of Aden and around Mauritius Island. Contrary to plans this was the most productive phase of the entire operation, the U-boats claiming 21 sinkings, totaling about 119,000 GRT.

    2. The sinking of the Charlotte Schliemann and the Brake.

      The Monsun return voyage went well until it became necessary to refuel the submarines, and the disaster accompanying this operation may be credited to radio intelligence. The refueling expeditions of the tankers Charlotte Schliemann (7,447 GRT) and the Brake (9,925 GRT) from January to March of 1944, while not of the first of their kind, were the first that the Atlantic Section had been able to follow currently. Both ships had refueled submarines in 1943, but in neither case was the traffic read in time to lead to the destruction of the participants. In the case of the rendezvous', however, the traffic containing the three crucial messages was broken by OP-20-G and was available well before the meetings were to take place, although the positions were at first incorrectly estimated. It is pertinent that both expeditions ended in the loss of the supply ship and a warning of compromise by the commander of one the submarines involved.

      In early January 1944, it became evident that the Schliemann was scheduled to refuel U-boats in the Indian


      Ocean. It had arrived Singapore from the China Sea area on about 24 December 1943, and on 13 January the Atlantic Section learned that it was to deliver supplies to homebound submarines.

      Besides the Monsun boats two others required provisioning: Eick (U-510), an Atlantic boat entering the Indian Ocean for operations; and U-IT-24 (pahls) an ex-Italian cargo submarine returning to Europe. The Schliemann's first task was to supply Eick and the Monsun boat Spahr, and a rendezvous was ordered beginning on 26 January at approximately 23°57'S - 68°E.

      The Schliemann left Singapore for Batavia on 8 January carrying 400 units of the fuel oil, arriving on the 11th. On 22 January it was learned by OP-20-G that the rendezvous had been shifted to a new position, later determined to be 24°03'S 67°52'E. The meeting was to take place at noon on or after the 26th, the supply vessel pulling off at night. To avoid the sinking of the ship by German submarines, attack on independents was forbidden south and east of 20° 15'S 64°33'E.

      The rendezvous was successful and uneventful, Spahr receiving cipher devices, provisions, 19 tons of rubber, fuel and a new fireman second class. The Schliemann was left with provisions for six submarines, 1,477 cbm fuel oil, 455 cbm Tarakag oil for Akira submarines, and 101 cbm lubricating oil. It was now possible to supply the other Monsun boats, and a message translated on 3 February ordered Junker to proceed to 22°30'S - 73°00'E for provisioning commencing the 11th. U-IT-24 was to be filled up on the 23rd at 31°03'S - 55° 12'E, and Lüdden on the 26th at about 31°S - 58°E.

      Junker met the Schliemann on 11 February, but the weather forced them to cruise south before fueling. Junker sighted a Catalina aircraft and submerged. When he surfaced he saw nothing but a Catalina on the 12th at 25°09'S - 72°55'E. After waiting two days he sent his report. He was ordered to wait two more days; but when he reported failure on the 22nd, COMSUBs was forced to change all plans and send the Brake to carry out the mission. The Charlotte Schliemann was sunk by HMS Relentless on 12 February in position 23°23'S - 74°37'E.

      The Brake, which had also been told in December that it would supply homeward bound submarines, seems to have been kept in reserve, COMSUBs evidently thinking that the


      Schliemann could take care of all demands in the January-March period. It had been reported in Batavia from 14 October to 25 November 1943 leaving on the latter date for Singapore to load 7,000 kilotons of #2 fuel oil. On 21 December and again on 13 January 1944, the vessel was, reported in Singapore.

      The Brake's inactivity was ended suddenly by the sinking of the Schliemann, leaving Junker, Lüdden, Pich, Schneewind, and U-IT-24 short of fuel and provisions; and it left port on about 29 February enroute to a new rendezvous.

      On the day following Junker's final report on his failure to meet the Schliemann, a message was read ordering him, as well as Lüdden and Pich, to meet the Brake in approximately 26°57'S - 68°E, on the 10th of March or shortly thereafter. Schneewind was to meet the supply ship about nine days later at 34°57'S - 63°E.

      Final orders were given Junker, Lüdden, and Pich in a message read by the Atlantic Section on 6 March. They were to rendezvous at noon on the 11th in position 31°57'S - 73°00'E. The fate of the Schliemann was still in COMSUBs' mind, for an intensive preliminary scouting of the rendezvous area was ordered; strict watch to be kept for aircraft, warships or heavy traffic. For this purpose Junker was stationed at the rendezvous point, Pich west of it and Lüdden north.

      The confusion incident upon the destruction of the Brake is reflected in the inconsistent reports made by the submarines present. But analysis of these reports gives the following picture. The Brake met Junker, Lüdden and Pich on 11 March at 31°57'S - 73°04'E. Lüdden was filled up, Junker received all but lubricating oil and Pich got part of his fuel but no lubricating oil. Bad weather then intervened, and the ships headed southwest in company. At 1056/12, in position 31°39'S - 72°32'E, a plane was sighted on the port beam. At 31°45'S 72°24'E, thirty-two minutes later, two more aircraft were sighted on the port beam. In seven minutes a flying boat appeared aft. Trails of smoke, with two aircraft above, bearing 1400T from 31°45'S - 72°24'E, were noted at 1210A. This was followed nine minutes later by artillery fire from the direction of the smoke. At 1320A/12 March, in position 31°45'S 72°16'E, the Brake sank. According to Pich, who rescued all but 4 of the Brake's crew, the vessel scuttle after being attacked by a cruiser and destroyer. The planes were reported as Albacore-type carrier aircraft.

      COMSUBs made no further attempts to refuel his boats.


      Lüdden was ordered to return to Europe, and the others, including Schneewind and U-IT-24, were forced to carry their valuable cargoes back to their Far East bases.

      Two strategically invaluable supply ships had been sunk one a month after the other. Both were caught almost exactly on the assigned rendezvous point after sightings by flying boats or carrier aircraft. It is significant that Junker, who had been present at both disasters, was of the opinion that "provisionings have been systematically compromised." (Shark 1809/12 March) No further submarine-surface vessel rendezvous were attempted. Of the eleven original Monsun boats, only one returned to Germany.


Table of Contents ** Previous Chapter (13)


1. This was U-234 whose cargo also included a shipment of uranium for Japan.

Transcribed and formatted for HTML by Chuck Roberts for the HyperWar Foundation