title graphic


Chapter VI

German-Japanese Cooperation in Communication Intelligence1

 

  1. Introduction: Little evidence of effective exchange.
  2. Early proposals 1942. German successes with British systems to be exchanged for Japanese assistance with U.S. navy systems.
  3. Tokyo's silence.
  4. The Joint Communications Agreements.
  5. German communications intelligence relayed to Tokyo via the German Naval Attach, August - September 1943.
  6. Cipher material for shipment to Japan, November 1942. Indication of German progress, November 1942. Merchant signals.
  7. Neglect of "Clause 7" and the Japanese Naval Attach's complaint of December 1943.
  8. Possible explanation of neglect Clause 7 in 1943.
  9. Cooperation 1944.
  10. An exchange on crypto-problem, May 1944.
  11. The situation in general combined intelligence, May 1944.
  12. Weakness of German intelligence, summer 1944.
  13. Concrete liaison July 1944. Description of German cryptanalytic activity.
  14. German requests.
  15. Japanese compliance.
  16. The Japanese Naval Attach's plans and instructions. Japanese proposals.
  17. Contents of material (traffic analysis) offered by Germany in 1944. Very similar to that offered in 1942.
  18. Material requested by Tokyo via dispatch.
  19. Critical situation, fall 1944.

-- 65 --

  1. Introduction: Little evidence of effective exchange.
  2. While information on German-Japanese cooperation in communications intelligence is still incomplete, it seems evident that effective exchange has never been established, despite the endeavors of the Japanese Naval Attach and apparent willingness of the German Navy to share its material. On the whole the past history of German-Japanese cooperation in communications intelligence seems to be an account of professions and intentions, without any evidence of combined efforts in attacking high grade naval ciphers. The Germans have talked darkly about their successes with such ciphers but there is no record here that the Japanese have ever done that much. This conclusion is based largely on the earlier Japanese Naval Attach traffic which became available in 1944, and on the few days of German Naval Attach traffic which have been read for 1942-1943.2

    The more recent dispatches of the German Naval Attach (including the Offizier messages) which have been read since the fall of 1944 lack any reference to joint cryptanalytic work. The summary given immediately below lists only those identifiable items which have been mentioned in available traffic as either exchanged or ready for exchange, but does not list the "operational intelligence" reports which have been seen in increasing numbers since the summer of 1944. Some of these may contain elements from communications intelligence, as indeed was claimed for a German report of December 1943 (see paragraph 7 below), but it is not possible to give a detailed derivation for them.

    1. Germany to Japan exchanges.
      1. BAMS intercepts (Indian Ocean).
      2. Via dispatch to German Naval Attach, Tokyo. Instances available from 1942, 1943, and 1944. Comment: Presumably passed for correlation with Axis submarine activity in Indian

-- 66 --

        Ocean. German information on current locations of Japanese submarines was apparently very limited, at least prior to the establishment of the U-boat base in Penang. In July 1943, for example, the Japanese Naval Attach stated that German navy had many radio intelligence reports of merchant vessels sending out submarine warnings in Arabian Sea, Oman Bay, and off the coast of Aden. The Germans presumed this was due to Japanese submarines and asked the Japanese Naval Attach to check. At this very time the German Monsun U-boats were departing western France for Indian Ocean operations and the establishment of the base at Penang.

      1. General information on British D/F via Japanese Naval Attach dispatch, July 1944.
      2. Comment: Germany recognized the "amazing progress" which England had made. Radio transmissions of over 10 seconds were certain to be D/F'd with effective and reliable results in the Indian Ocean as well as the Atlantic. It is interesting to note that in another dispatch of the same day (10 July) the Japanese Naval Attach accounted for the loss of the Satsuki #2 as follows: ". . . she was first located by D/F . . ."

      3. Traffic analysis.
      4. British naval frequencies, British call signs and call sign construction (ready for shipment November 1942). The same with addition of similar information on U.S. Navy and outline of joint British and American naval communications (principally for Atlantic and Mediterranean). (to be shipped August 1944, not sent). This material was requested by dispatch in view of transportation difficulties. (Sent by dispatch fall of 1944).

      5. Captured documents
      6. "Merchant navy code." (included in material ready in November 1942.)

      7. Merchant signal recoveries, 1942.
      8. Included in the material ready in November 1942 with promise to include any subsequent recoveries.

-- 67 --

      1. Presumably from decryption, exact source unknown.
      2. Via dispatch to German Naval Attach, 9 September 1942. Merchant vessel movements, Allied escort rendezvous' in Indian Ocean.

    1. Japan to Germany exchange.
      1. BAMS intercepts.
      2. Via German Naval Attache 1944.

      3. Allied anti-submarine aircraft reports.
      4. Via German Naval Attach. One instance known, July 1944, and this may have been a BAMS. There was also the operation Transom deception message which the Japanese reported on request.

      5. Allied submarine positions and ship movements.
      6. The submarine positions have been seen in increasing quantities in German Far Eastern communications with growing U-boat activity in Japanese waters.

      7. Decryption.
      8. Via German Naval Attach dispatch 26 October 1944. Only instance seen here. Japanese communications intelligence deciphered a message "from New Dehli to agents (probably in Penang) containing request for information on German U-boat armament and speeds."

  1. Early proposals 1942. German successes with British systems to be exchanged for Japanese assistance with U.S. Navy systems.
  2. As early as January 1942, the Japanese Naval Attach was reporting very favorably on German progress in decryption and was urging joint research in cryptanalytical

-- 68 --

    work. He was confident that the Germans would solve the problem, "even though they have troubles in the methods to be used in attacking the fundamentals."

    There was also a "change" which would "give some trouble in breaking the systems," but the Germans had already achieved some finished results. They have been working at it very cleverly and have recently broken into the English Navy systems with some success, and have gotten some clues to solving the U.S. Navy systems." Lacking adequate data on U.S. Navy systems, the Germans hoped to meet this need through joint research with the Japanese. The Japanese Naval Attach proposed that intercepts of what the Japanese regarded as the principal U.S. Navy systems be forwarded via the German Naval Attach to Germany, where "the Germans will endeavor to break them." It is clear that the Japanese Naval Attach approved of the proposal, at least as a temporary measure, "although you (Tokyo) may be considering other plans ..."

  1. Tokyo's silence.
  2. The reply from Tokyo is not available. If any was sent at all, it was surely non-committal, for in April 1942, the Japanese Naval Attach brought the subject up again. It was apparently necessary to remind Tokyo that "The cryptanalytic section of the German navy is organized on an extremely large scale, and seems to be obtaining fairly good results." For the third time Tokyo was informed that the Germans desired cooperative investigations, "from the standpoint of joint operations," and were willing to turn over their decryption methods, "especially those on U.S. Navy systems."

    The Japanese Naval Attach had planned to assign a Lieutenant Commander Mishina to joint work with the Germans in these matters but this officer had been transferred and no qualified person was now available. The Attach respectfully inquired of his superiors whether they might be disposed to send a specialist on the submarine which was about to leave for Germany (presumably I-30). It is unlikely that the I-30 carried such a specialist to Europe, but on her return trip to the Orient she did carry secret documents and a shipment of German ENIGMA cipher machines, some of which were unloaded in Singapore before the submarine struck a mine and sank.

-- 69 --

  1. The Joint Communications Agreements.
  2. In June 1942, Vice Admiral Nomura reported the clauses of the "German-Japanese Naval War Communication Agreement" which had just been concluded with Vice Admiral Maertens, then Chief of Naval Communications. The 7th Clause provided that:

    "The Japanese and German Navies will collaborate in regard to radio intelligence."

  3. German communications intelligence relayed to Tokyo via the German Naval Attach, August - September 1943.
  4. The few days of German Naval Attach traffic which have been read for 1942 suggests that Germany made a show of compliance with "Clause 7." The German Naval Attach received intercepts of U-boat sightings broadcast (BAMS) for the Indian Ocean area, and on 9 September he received what appeared to be results of German decryption, giving the movements, passage points, and speeds of the following ships in the Indian Ocean: Helen Moller, Catrine, British Sovereign, American transports Cremer and Maetsuyeker, and the Australian Manunda.

    In addition, the German Naval Attach was informed that at 0600/8 September an Allied unit was to relieve another unit in 23°15'S - 90°10'E (about 1440 miles northwest of Perth). The above items bore "B" serial numbers and were probably taken from current German communication intelligence bulletins. It is unfortunate that evidence available is not sufficient for judging the extent of German communication intelligence information which reached the German Naval Attach in the above manner.

  5. Cipher material for shipment to Japan, November 1942. Indication of German progress, November 1942. Merchant signals.
  6. A message of 26 November 1942, from the Japanese Naval Attach stated that in response to Tokyo's request the Germans had turned over certain material on the British merchant shipping code and had promised to "organize any recoveries made hereafter and deliver them by the time the

-- 70 --

    submarine is ready to leave."3 Matters urgently needed by the Japanese were to be forwarded by dispatch upon request. Contents of the material then available:

    1. 200 pages of British naval frequencies and call signs of every sort, including main points of call sign construction, "but apparently practically no specific call signs for vessels are included."
    2. "Merchant Navy Code." The Germans held an original of the document itself and were supplying photographic copies to the Japanese. The British had changed the key words and the substitution table on 15 March 1942, but the basic code appeared to be the same and the Germans were gradually accumulating the number of messages needed to recover the new key words and substitution table. As of November, they had recovered only about 20 of the new key words of the new key word groups.4

  1. Neglect of "Clause 7" and the Japanese Naval Attach's complaint of December 1943.
  2. The Japanese Naval Attach traffic for 1943 which has been seen in the Atlantic Section is singularly lacking in any references to the project for cooperation in radio intelligence. It is evident from the Japanese Naval Attach's complaint in December 1943, that the whole business had fallen into neglect, at least as far as Japanese assistance was concerned. To what extent the Germans had continued to send cryptographic material is not known,5 but they had at least given the Japanese some operational information gained from radio

-- 71 --

    intelligence, for it was an instance of this that occasioned the Japanese Naval Attach's complaint.

    German radio intelligence had warned Japan via the German Naval Attach in Tokyo that the Americans were preparing to challenge the increasing activity of Japanese ships and convoys in the northern New Guinea area. The situation was compared to that which immediately preceded the Battle of the Solomons. The Japanese Naval Attach shared the German fear that a sudden change was imminent and introduced his plea for cooperation by pointing out the obvious: "If, at this time we could learn the plans of the enemy of the movements of his vessels, it would help us considerably in planning our own operations."

    The Germans, he declared, fully appreciated the importance of crypto-intelligence, but, although doing their best with limited personnel, they were handicapped by lack of material. "By mutual exchange of material between Japanese and German navies, it is hoped that there will be a gradual development of cryptanalytical intelligence. Even when it is difficult to get concrete decrypted material, analyses should be possible." The Germans had evidently put the Japanese Naval Attach in an embarrassing position, if one may judge from the following paragraph which summarized his own reactions:

    "With regard to our cooperating in this matter, although it was our intention to exchange information frequently, these exchanges have been reported on the general war situation. At a time when one feels more than ever the necessity for mutual alliance and cooperation between Germany and Japan, the best plan for Japan is not to change the obligations set forth in the communications agreement. It is an important matter from the point of view of joint operations. In addition to considering this matter anew, I humbly urge that we do all we can to realize cooperation in this matter. (Where nothing else is possible, we can at least exchange information about this problem)"

    A further statement is ambiguous, but seems to imply that the Japanese Naval Attach recognized how little material

-- 72 --

    of operational value the Germans could actually furnish the Imperial Navy at that time.6

  1. Possible explanation of neglect Clause 7 in 1943.
  2. In view of Germany's initial determination not to share her technical advancements with the Japanese, notably the T-V acoustic torpedo, it is quite possible that she had not been completely honest with Japan in matters of radio intelligence. It will have been noted that the material being prepared for shipment to Japan in November 1942 did not include naval ciphers or codes, at least no mention was made of anything but Merchant Ship Code. Yet the British recorded cases in 1942 of German successes with Naval Cipher #3. Certainly U-boat traffic up to the summer of 1943 showed an impressive total of German decryptions in Naval Cipher #3, and some successes with Naval Cipher #5 was obtained in the fall of 1943.

    It is conceivable that the Germans might have shown these to the Japanese Naval Attach and have convinced him that they were of operational value to the Germans only, but it seems more likely that for security reasons the Germans kept these things to themselves and did not press for cooperation until things began to go badly for them. Such an explanation could, of course, work equally well from Tokyo to Berlin and mean that the reluctance of the Japanese to share with the Germans was based on reasons of security. Certainly the professions of mutual aid revived and became increasingly vigorous as Axis fortunes waned in 1944.

  3. Cooperation 1944.
  4. The first actual statement from Tokyo on communications intelligence ever seen in the Atlantic Section bore the date 3 February 1944.

    "With regard to Japanese-German Naval collaboration in the matter of radio intelligence, we intend to make it our policy henceforth to cooperate in as positive manner as possible; but the situation at present is that as yet little of the material we

-- 73 --

    have on hand is worth offering to the Germans. At present, every time special information that seems important is derived from radio intelligence reports, it is communicated to the German Attach in Tokyo . . ."
    (Remainder of this message was not intercepted.)

    As far as it is known here, and especially subsequent to 3 February, this cooperation has been largely confined to the relay of submarine sighting and attack reports in the Indian Ocean and to the relay of Allied submarine locations in East Indian waters. While information is admittedly scant, the following case from May 1944 may be characteristic of actual German-Japanese cooperation.

  1. An exchange on crypto-problem, May 1944.
  2.  

    On 16 May 1944, the Germans intercepted an aircraft sighting report of a naval task force which had been relayed by Colombo, and sought to exploit it with the assistance of the Japanese cryptanalysts.

    18 May German navy requested via Japanese Naval Attach any information which could be used in connection with the intercept.
    25 May Tokyo replied but could not help. The Japanese had likewise picked up the sighting report. They assumed that the aircraft had mistaken an Allied for an enemy task force, although it was also deemed possible that the report had been a deception message.
    Comment The sighting report was part of a deception plan for operation Transom and was sent in self-evident code.7

  3. The situation in general combined intelligence, May 1944.
  4. Meanwhile, on 20 May, the Japanese Naval Attach raised the whole subject of general combined intelligence, and in so doing provided the following summary of the situation as of that date.

-- 74 --

    1. The Japanese maintained liaison in operational intelligence.
    2. "German Navy and Air Force are now offering the intelligence reports that had not previously been given to the Japanese."
    3. The Germans were "having trouble getting current intelligence and the operations sections of all the services pay close attention to the Japanese intelligence reports."
    4. The Japanese had, however, sent little useful information and the Germans were dissatisfied. Germany did not understand why Japan did not furnish special material, for example, from prisoners of war and from their Attach in Russia.
    5. Tokyo was requested to send weekly:
      • "Our intelligence reports."
      • "Lessons learned in air in naval battles with the English and Americans."
      • "Weekly War Reports" from the Navy.

      The Japanese Army weekly war reports were already being received.

  1. Weakness of German intelligence, summer 1944.
  2. That the Germans were having trouble in getting current intelligence late in May 1944, was well demonstrated by the Allied landings in Normandy and the subsequent campaign. According to the reports which the Japanese Naval Attach and Ambassador Oshima were receiving from German Headquarters and relaying to Tokyo, the Germans were not only surprised by the landings but continuously and grossly underestimated the number of troops which gathered in Normandy during June and July. At the time of the breakthrough at St. Lo, the Japanese representatives in Germany were informed that "Patton's Army" was still in England, whence he threatened an invasion of Dieppe throughout July.

-- 75 --

  1. Concrete liaison July 1944. Description of German cryptanalytic activity.
  2. Following a very friendly interview with Rear Admiral Stummel, Chief of Naval Communications, the Japanese Naval Attach declared on 10 July that he had begun concrete liaison with the head of Naval Communications Intelligence, who at once agreed to place Japanese in the German communications intelligence organization. Furthermore, the Germans would make up a shipment of all types of communications intelligence material now on hand for forwarding on the Japanese submarine which was soon to reach Lorient. Meanwhile, however, it was requested that the Japanese indicate just what problems were of especial interest to them. During this visit the Japanese Naval Attach learned the following about the German organization:

    Two main sections: Evaluation
    Cryptanalysis
    Total personnel: About 800

    German difficulties were blamed on Italy's betrayal, which had increased Allied security measures.

    "English and American countermeasures are very vigilant (secure), especially since Italy's 'Stab in the back' of last year when the communications intelligence situation was realized by the enemy. At present, although they are bending every effort, the results are not satisfactory. It is said that this is especially true where American communications are concerned."

  3. German requests.
  4. The Germans in turn made certain demands upon the Japanese, of which the last is somewhat surprising:

    1. "All types of British and American material, including captured documents."
    2. "Absolutely all available information on the disposition of the British and American fleets."

-- 76 --

    1. "They would also like to have the forms of all Japanese naval traffic so that they can distinguish them from British and American traffic."

  1. Japanese compliance.
  2. Tokyo complied with this last request on 26 July sending a brief description of "the external form of Japanese naval communication" in terms of the different types of call-signs and the different types of textual grouping.

  3. The Japanese Naval Attach's plans and instructions. Japanese proposals.
  4. As part of his immediate program for cooperation the Japanese Naval Attach planned to assign his special secretary to duty with the German organization, "after the code clerk on the Momi arrives." Before going further, however, he apparently wanted "to know as soon as possible the views and desires of the central authorities concerning this matter." The Momi (I-52) with its code clerk never made port, but the central authorities did communicate their views. Two and one half years after the first known discussions of Clause 7 the Japanese Naval Attach was being told that "We desire that you negotiate as fully as possible with the Germans in this matter." The Japanese proposed the following steps:

    1. The assignment of Japanese research specialists to the German organization, in order to effect technical liaison. Four to be sent from Japan by next submarine transport, two reserve officers and two non-coms, prepared to stay in Germany for approximately one year. In the interim qualified special clerks now attached to the Japanese Naval Attach's office will be assigned.
    2. "If occasion warrants," German specialists to be employed in joint research in Japan.
    3. Exchange of Material:
      1. Material offered by the Germans to be sent on the Momi's return trip.

-- 77 --

      1. Material offered by the Japanese to be sent be German vessel or by next Japanese cargo submarine.
      2. "For the immediate present we will exchange material gathered since the last time (August of last year)."
      3. Comment: If the above statement means a mutual exchange, it may refer to the I-8 (Flieder) which arrived west France in late in August 1943 and to the U-511 (Satsuki #1, RO-500) which reached Japanese waters in August. It is not known here that these submarines did carry such material. There are no known departures of submarines in either direction during the month of August which might fit the above.

  1. Contents of material (traffic analysis) offered by Germany in 1944. Very similar to that offered in 1942.
  2. On 25 August 1944 the Japanese Naval Attach reported that he had received the material which had been destined for the Momi's return trip and that he would forward it by the next appropriate transportation.8 The Imperial Navy could judge from the list of contents what was of immediate necessity, extracts of which could be sent by dispatch. The contents were:

    1. British navy: call signs (shore stations, ships, convoys), frequencies, communication circuits, areas, abbreviations, British and American merchant ship call signs, outline of British and American naval (joint) communications.
    2. American navy: as above. Also "American Army field radio cipher machine (it cannot be heard by ear)."
    3. The above material applied principally to the Atlantic and Mediterranean areas; information on Indian and Pacific Ocean areas was not abundant.

-- 78 --

  1. Material requested by Tokyo via dispatch.
  2. On 31 August Tokyo requested that the following be sent by dispatch:

    1. On the British: call signs for ships and escorted convoys and the basis for their deduction. Various types of abbreviations. Outline of communications used between the British and American navies, including call signs, code identification, frequencies, procedure, etc.
    2. On the American navy: Structure of the "KU numeral-letter" call sign system, and period of its use. Basic material necessary for traffic analysis. (i.e., material which has appeared in the past where there has been a connection between operations and communications conditions.)

  3. Critical situation, fall 1944.
  4. One assumes that efforts toward cooperation have increased since the summer of 1944 with the dangerous situation in which both Germany and Japan find themselves. It is evident, however, that the situation itself tends to defeat these efforts, for exchange other than by dispatch has been practically impossible. The report of an interview between Vice Admiral Abe and Admiral Meisel on 30 October sounds characteristic of the Axis plight. Admiral Meisel pointed out that:

    "It is extremely important to Germany, fighting a defensive battle, to fix the time and place of enemy attacks. Especially at this time, when there is a great possibility of enemy landings in Norway, the Germans are uncertain as to the place selected."

    "In view of the brilliant successes of the Japanese Navy" in repelling the October thrusts of the U.S. Navy, Admiral Meisel asked whether the Japanese had used special long range reconnaissance planes "or did it have any other special help!" "Other special help" surely includes communication intelligence. Vice Admiral Abe replied diplomatically and referred the matter of "lessons gained from the battle" to Tokyo.

-- 79 --

    The persistent "shelving" by the Japanese of German requests for information which was of the utmost importance as the situation became more desperate, and their long standing neglect of Clause 7 had begotten a similar attitude on the part of the Germans by March of this year. Vice Admiral Abe urged Tokyo to release more operational information and estimates of enemy plans together with Japanese counterplans. He complained that the lack of such information was making effective liaison virtually impossible, that conferences with German officials were difficult to arrange and when arranges, he received the same "diplomatic" treatment which it had formerly been his habit to administer.

    By comparison with the German attitude indicated above there is some inconsistency in the message to the German Naval Attach, transmitted the day before the Japanese Naval Attach's report to Tokyo. The consent contained therein for the formation of a German Armed Forces communication intelligence liaison with the Japanese General Staff may have been inspired by the hope that more practical results could be obtained by cooperation in Japan than via the existing communication system.

    Concluding notes:

    The following additional information was made available through traffic read subsequent to the writing of this chapter.

    A report from the German Naval Attach in September 1942 (only part of which was intercepted) implies that the Japanese were more concerned at that time with the possible compromise of their own ciphers than with decryption of enemy ciphers.

    "At desire of Japanese Navy prolonged conference was held 29 August on basic communication questions: documents captured at Nanking showing disposition of Japanese fleet have apparently aroused the impression that their own communication service is inadequately secure. Japanese communication practices is modeled on English and American. Crystal controlled transmitters. Cipher procedure only by hand

-- 80 --

    substitution. Radio, cipher and technical personnel separate; each understands only part of the field. Control station procedure unknown."
    (PPA 91, #469 2 September 1942)

    More than a year later, in March 1945, even the reports on the general war situation mentioned above were being sent to the Germans in a form which indicated only a perfunctory consideration for cooperation. In an exchange of information reviewing the general war situation between the German Naval Staff (Rear Admiral Wegner) and the Japanese gave "information on the Greater East Asia Area situation and general conditions, based on weekly intelligence reports of the army." The lack of current and specific information from Tokyo again placed the Japanese Naval Attach in an embarrassing position for, in response to questions concerning Japanese submarines in the Singapore area, he was forced to refer to a German intelligence report on submarine operations. Hence his request, included in the report, that the Japanese Naval Staff "arrange immediately to furnish the report on the war situation in Greater East Asia and in the general situation requested in 'N' Serial #299" as well as information regarding the present and future policy in regard to submarine operations in the Indian and Pacific Oceans. (JNA #049, 03/080900/45)

-- 81 --

References

Paragraphs References
1 JNA #675, 07/061830/43
JNA #209, 07/102000/44
2 JNA #087, 01/24/44
3 JNA #313, 04/071800/42
4 JNA #277, 03/271200/42
JNA #511, 06/151200/42
5 1520/21/8/42, Diplogerma
9/9/42, #75-78, Diplogerma
6 JNA #546, 11/26----/42
7 JNA #150, 12/211230/43
9 JNA #386, 02/031600/44
10 JNA #943, 05/182000/44
                  05/252330/44
11 JNA #970, 0520 2000/44
13, 14 JNA #197, 1130/10/7/44
15 JNA #750, 1150/26/7/44
16 JNA #751, 2100/26/7/44
17 JNA #355, 2200/25/8/44
18 JNA #825, ----/31/8/44
19 JNA #649, 1000/4/12/44
JNA #035, 03/011350/45
PPB 31, 2 March 1945

--82--

Table of Contents
Previous Chapter - Chapter V   *   Next Chapter - Chapter VII


Footnotes

1. Based on information available as of 8 December 1944.

2. See note at end of Chapter.

3. The submarine referred to may have been one of the German submarines which sailed for the Indian Ocean early in 1943, either U-180 which departed Kiel on 8 February 1943 to rendezvous with the I-29 in April, or the U-511 which departed Lorient on 10 May 1943, carrying Admiral Nomura home.

4. The B-Dienst captured a copy of the new codebook, in the Arctic theater, four weeks before it came into effect.

5. There seems to have been at least one exchange in 1943. See paragraph 16 below.

6. See note at the end of the Chapter.

7. Operation Transom was the 17 May 1944 Allied carrier raid on Soerabaya.

8. The large consignment (70) of German ENIGMA machines and all non-crypto material destined for the I-52 were destroyed at Lorient in September.



Transcribed and formatted for HTML by Rick Pitz, HyperWar Foundation