SRH-232

US Navy COMINCH

Radio Intelligence Appreciations Concerning German U-Boat Activity in the Far East
(January—April 1945)

Declassified per Para. 3, E.O. 12356 by Director, NSA/Chief, CSS

Date: 2 March 1983


Far Eastern Situation
COMINCH appreciation number one
My 221317 refers

Para one
Only two German U/bs remain in southern ports following the recent departure of four (U-843, U-510, U-532, U-861) on transport cruises to Norway. Both are cargo U/bs. U-181 arrived Singapore on 15 January for bearing repairs after an abortive start for Atlantic. U-219, lately arrived from the Atlantic, was damaged when a Jap munitions ship was torpedoed and blew up in Tandjok Priok late Dec and is now being repaired in dock at Batavia. Completion date end of February war readiness mid-March.

Para 2
Two U/boats are in Kobe for battery exchange. U-183, a 740 tonner, will depart about 9 February for Batavia and after refuelling in Balikpapan is expected to operate against US traffic between New Guinea and Mindanao alternatively New Britain-Palau area. U-IT-25, Ex-Italian Cargo U/b, is scheduled to leave Kobe early March. A similar type, U-IT-24, is now enroute Kobe from Singapore to deliver cargo and obtain new battery.

Para 3
U-862, a 1200 tonner, is returning to Batavia via Sunda Strait from operations off Australia. U-195, a cargo carrier, will return to Batavia in about two months after refuelling an Atlantic bound U/b probably south of Madagascar. U-871, a 1200 tonner, may be approaching Batavia via Sunda Strait from operations in Gulf of Aden, although it is probable this U/b was sunk in Atlantic last September. U-537 and U-863, whose return to port has been ordered, are both considered sunk.

Para 4
Batavia is now the main German U/b operating base in the Far East; Soerabaja and Singapore are repair ports with latter headquarters for German CO of southern area (Fregattenkapitan Dommes). U/b fuel is brought to these ports from Balikpapan by two 12000 ton surface tankers, Quito and Bogotá, which also transport supplies between the southern bases. Evacuation of the southern area by all German U/bs is being considered in event Japs move out.


Far Eastern situation
COMINCH appreciation number two
My 221317 January refers

Para One
U-IT-24 left Singapore for Kobe 1 February suffering a battery explosion 3 February but is continuing cruise. Best estimate of speed 180 miles per day plus or minus 30 miles. This U/b is expected to cruise mainly on surface in view of worn battery and explosion. Known points on route are 09-55N 107-36E, 11-1BN 109-14E, 20-25N 112E and 22-50N 119-36E.

Para 2
From latter position U-IT-24 track may pass approximately via 24-37N 120-04E, 28N 122-45E, 31-11N 125-46E and 33-31N 128-30E which was route taken by U-183 on voyage to Kobe last October (later Jap RI may clarify onward route of U-IT-24).

Para 3
As this U/boat is carrying important cargo including new German cipher for Berlin-Tokyo traffic whose use would result in the loss of much valuable information, it is considered that U-IT-24 offers a most valuable target.


Far eastern situation
COMINCH appreciation number three
My 221317 January refers

Para one
U-862 arrived Batavia 15 February from operation in Australian waters having torpedoed the Robert Walker 24 December off Sydney and the Peter Silvester 6 February about 800 miles west of Perth. This U/b arrived Singapore 20 February presumably for overhaul. U-181 is at Singapore undergoing major engineering repairs which are expected to take until June, including fitting by Japs of rigid schnorchel.

Para two
U-219 remains at Batavia to which port U-195 will return from the Indian Ocean via Sunda Strait about the first part of March. Ultimate return of both these cargo U/bs to Germany without battery renewal is intended.

Para three
U-IT-24, due to arrive Kobe 18 February from Singapore, reported having passed 24 North 11 February and 30 north 14 February. New Tibet cipher carried by this U/b was promulgated 21 February by German Naval Attaché Tokyo. Departure of U-183 from Kobe for Batavia was delayed until about 22 February. Her scheduled noon positions for 25 to 27 February are 30-07N 124 03E and 26-50N 121-32E and 22-unknown minutes north 119-38E. This U/b will not be able to reach a tentative operating area in the Philippines until the end of March by which time German Naval Attaché Tokyo expects US supply traffic will proceed directly from Guam to new beachheads. U-IT-25 is still scheduled to depart Kobe southbound early in March.

Para Four
German CO of southern area is now stationed at Penang. Bogotá left Singapore 17 February with supplies for Batavia and was scheduled to return 20 days later.

Para Five
U-864, a 1200 ton U/boat scheduled to depart shortly for the Far East, was sunk off Bergen on 9 February by a British sub. At present there are no indications of any U/boats in the Atlantic which are enroute to the Far East.

Far eastern situation
COMINCH appreciation number four
My 221317 January refers

Para One
Two 1200 ton U/bs are undergoing overhaul at Singapore. U-862 with 66% battery capacity, will be ready to depart end of April except for desired rest period for the crew. This U/b is to load as much rubber as possible and carry 8 torpedoes for interim operation off south east African coast enroute to Atlantic. U-181 will have limited navigating capacity by middle of April and final readiness including installation of rigid schnorchel by first June for departure Germany with cargo.

Para Two
U-183 arrived Batavia 9 March from Kobe. As of 5 March she was still scheduled for offensive operations in Southwest Pacific. U-219 is at Batavia undergoing repairs to be completed end of March. U-195 arrived Batavia 4 March from refueling task Indian Ocean and departed following day for Soerabaja arriving 7 March.

Para Three
Bogotá arrived Singapore 17 March. Quito was due to sail Batavia shortly after 14 March to load U/b fuel at Balikpapan.

Para Four
U-IT-24 arrived Kobe 18 February for battery exchange. Further repairs deferred departure date of U-IT-25 from Kobe southbound until early April.
Para Five
German Naval Attaché in Tokyo was informed by Berlin on 8 March to count on only two U/bs (U-234 and U-876) going to southeast area, leaving Germany in March and April. Each will be a transport U/b carrying only 8 torpedoes for possible operation enroute. Comment: U-876 is a 1200 tonner X U-234 is a 1600 tonner for which charts of Tierra Del Fuego and Pacific areas have been requisitioned suggesting route via Cape Horn. Both U/boats are currently estimated in the Baltic. On 14 March Berlin informed Tokyo there was no longer any possibility of delivery new merchant ship recognition signals before August 1945.

Far Eastern situation
COMINCH appreciation number Five
My 221317 January refers

Para One
U-183 undergoing diesel repairs at Batavia since 15 March is scheduled to depart 21 April for offensive operations in area north of New Guinea to 05N and east of Morotai to 153E. Enroute to pass through following points: 05-15S 10S-00E, 04-49S 114-41E, 04-15S 116-51E, 03-18S 118-25E, 00-39S 118-13E, 01-30N 120-40E and 05N 125-20E. Noon positions: 22 April 05-12S 109-30E, 23 April 04-54S 113-30E, 24 April 04-00S 117-18E, 25 April 02-00S 11, 8-18E, 26 April 00-18S 118-30E, 27 April 01-12N 119 Recognition Signals: two white lines on forward deck and Jap flag displayed on C/T. Night time: Jap challenge JIG Peter (Alternate King Queen) German reply dog uncle (Alternate easy victor).

Para Two
U-219 has been loading cargo at Batavia and was scheduled to leave drydock end of March with two weeks rest for crew prior to departure for Atlantic. There is yet no confirmation of her sailing.

Para Three
U-195 at Soerabaja undergoing repairs expected to be completed middle of May. She will have limited cruising capacity after 20 April.

Para Four
U-181 and U-862 are at Singapore, with the latter scheduled to sail for Atlantic in May. U-862 is to proceed directly to Southeast African coast for interim operations, Berlin having refused request by Jap navy that she land agents off Madras coast enroute.

Para Five
U-IT-24 and U-IT-25 are still at Kobe for repairs further delayed by bomb damage to dockyard. Repairs to U-IT-25 will require at least three months. She may even be scrapped.

Para Six
Quito while approaching Balikpapan from Batavia escorted by sub-chaser was strafed and slightly damaged by three B-24s 1920 to 2045/12 April. Bogotá scheduled to arrive Batavia 20 April from Singapore with her next port of call probably Soerabaja.

Para Seven
Berlin intends to abandon as German bases Penang and one other port to be designated by German CO of southern area whose HQ is now at Seletar (Naval Harbor Singapore).


Source: Cryptologic Documents Collection, Navy Department Library. Also available at the National Archives and Records Administration, College Park, Maryland, in Record Group (RG) 457, Records of the National Security Agency.


Note: The opinions expressed in this document are those of the author and do not necessarily represent the views of the Naval History & Heritage Command.