S E C R E T

NAVY DEPARTMENT

OFFICE OF THE CHIEF OF NAVAL OPERATIONS

WASHINGTON

Final Report - G/Serial 30

REPORT ON THE

INTERROGATION OF SURVIVORS FROM U-231

SUNK 13 JANUARY 1944

S E C R E T

TABLE OF CONTENTS

				Page
CHAPTER	I.		INTRODUCTION	1
	II.		DETAILS OF U-231	3
	III.		TECHNICAL DETAILS AND PROCEDURES	10
	IV.		TACTICAL REMARKS	17
	V.		CREW OF U-231	20
	VI.		EARLY HISTORY OF U-231	24
	VII.		FIRST PATROL OF U-231	27
	VIII.		SECOND PATROL OF U-231	35
	IX.		THRID AND LAST PATROL OF U-231	39
	X.		SINKING OF OF U-231	42
	XI.		OTHER U-BOATS	48
	XII.		MORALE	63
ANNEX			CREW LIST OF U-231 AND U.S. EQUIVALENTS OF GERMAN NAVAL RANKS

CHAPTER I.  INTRODUCTION

        U-231 was sunk by several well placed depth charges dropped by Wellington L/172 at about 2230 Z, 13 January 1944, in position 44.15 N, - 20.38 W.  The 500 ton U-boat was commanded by Kapitänleutnant Wolfgang Wenzel, who had commissioned the boat on 14 November 1942.  U-231 had been at sea for a total of 121 days and had been singularly ineffective, never having sunk anything.  She was sunk while underway 18 days on her third patrol.

        The entire crew of 50 escaped from the sinking U-boat, but seven men died of exposure or drowning.  Forty-three men, including the commander, the executive officer, the 2nd watch officer, the engineering officer, and the doctor were rescued by U.S.S. PARROTT and U.S.S. BULMER.  The prisoners were later transferred to U.S.S. BLOCK ISLAND which landed them at Norfolk 3 February 1944.  After a brief interrogation of the entire crew 14 prisoners were brought to an interrogation center.

        The progress of the interrogation was slowed considerably by the extreme security-consciousness of the prisoners.  This was partly due to the fact that Kapitänleutnant Wenzel was a rabid Nazi and that many of the younger members of the crew were deeply steeped in Nazi ideology.  Morale had also been boosted by the alleged sinking of an Allied destroyer just one day prior to their own sinking.  In due course, however, interrogation proved fruitful.  

 

        U-231 was the first U-boat equipped with the new automatic

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37 mm. gun from which prisoners were taken.  Much information regarding the new weapon was obtained.  However, the prisoners from U-177, which was sunk on 6 February, were able to elaborate on the features of the automatic 37 mm. gun, and, in view of this, all information gained will be published in the interrogation report on U-177.

        The special features of this report are contained in Chapters III and IV.  Attention is drawn to the new H/F D/F set, to the procedure of A/C and U-boat cooperation, and to the complete drawings of the radio room and listening room aboard U-231.

        U.S. Navy equivalents of German ranks will be found in the Annex.

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CHAPTER II.  DETAILS OF U-231

TONNAGE

        500 tons.

TYPE

        VII-C.

BUILDING YARD

       Germania Werft, Kiel.

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DISTANCE FROM PRESSURE HULL TO DECK GRATING

        Normal.

MAXIMUM DEPTH ATTAINED

        220 meters.

CRASH DIVING TIME

        29 seconds to 15 meters.

BRIDGE ARMOR

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AMMUNITION

        (a)  For 20 mm. guns:  5,000 rounds carried.  New type of ammunition may have been carried.  (See Chapter III).

        (b)  For 37 mm. automatic gun:  New ammunition with high explosive power.  Referred to as "Minemunition" (mine ammunition).

        (c)  For demountable machine guns:  10,000 rounds.

READY AMMUNITION LOCKERS

        One pressure-proof ammunition locker aft of periscope housing; 4 lockers located between Platforms I and II, 2 over 2.

TORPEDO TUBES

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TORPEDO STOWAGE ON LAST PATROL

        2   F.A.T.-2 torpedoes in tubes 1 and 3.

        2   T-5 torpedoes in tubes 2 and 4.

        1   T-5 torpedo in tube 5.

        1   T-3 torpedo above floor plates in forward torpedo compartment.

        1   T-3 and 3 F.A.T.-1 torpedoes under floor plates in forward torpedo compartment.

        1   T-5 torpedo on floor plates in stern torpedo compartment.

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installed after return from the third patrol.  (See also Chapter III).

DIESELS

        Two G.W. 6 cylinder, 1400 h.p. Diesels.  R.P.M. speeds practically identical with the installation in U-664 (G/Serial 27).

SUPERCHARGERS

        Two "Kapselgebläse"  (Roote's type).

FUEL OIL CAPACITY

GERMAN ASDIC

        Not fitted.

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RADAR

        Not fitted.  U-231 was originally equipped with a radar set, the dipoles being fitted around the forward part of the conning tower.  After the first patrol the set was dismantled, but the dipoles were only removed after the second patrol.  The rods to which they had been fastened were left in place.  The radar was never used while on patrol.

RADAR DECOY BALLOONS

        Carried in 4/5 boxes.  One balloon was recovered by U.S.S. BULMER about 20 miles north of U-231's survivors' position.  (It is doubtful that this had belonged to U-231.)

G.S.R.

        Wanz G-2, 2 "Naxos" sets, and a "Borkum" set.  The G.S.R. sets covered the following wave bands:  Naxos:  8 - 12 cm; Borkum:  30 - 300 cm;  Wanz G-2:  120 - 180 cm.  (See also chapter III).  On first patrol U-231 carried a Metox R 600 with cross-type aerial.  On second patrol a Wanz G-1 was fitted.

D/F GEAR

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        (c)  40 watt emergency transmitter fitted.  This was used frequently in the Bay of Biscay on certain short waves not well suited for the 200 watt transmitter.

        (d)  U.K. gear not fitted.

REMOTE TRANSMITTER CONTROL PANEL

        Fitted - See Plate VI.

UNDERWATER TELEGRAPHY

        Fitted.  Used once in mid-Atlantic to contact another U-boat making a diving test.  However, no reply was received.

RECEIVERS

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CHAPTER III.  TECHNICAL DETAILS AND PROCEDURES

REMARKS ON T-5 TORPEDO

        T-5 torpedoes carried by U-231 had the plastic nose filled with liquid, not the type open to sea water carried by U-172.

        It was stated that these torpedoes are so sensitive as to be easily rendered useless by the explosion of depth charges in the vicinity of the U-boat, even when the U-boat itself sustains little or no damage.

        The propellers of T-5 torpedoes were said to be the same as those on any ordinary electric torpedo.

        The entire top surface of T-5 must be kept free of grease.  The body of the torpedo was stated to be homogeneous, of metal, no plastic, and without any inlaid strip along the top.  T-5 torpedoes carried on U-231 were withdrawn from the tube part way for charging only; when the charging was finished, the cover plate was wiped.  T-5 torpedoes were never withdrawn entirely from the tube for wiping.  This would have been done only if water were admitted to the tube and then expelled.  No reason could be advanced why the top surface of the torpedo was to be kept free of grease.  A rating was told to be careful of the torpedo at all times and to be especially careful to protect the nose while loading.

DEVELOPMENT OF A T-6 TORPEDO.

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T-5 but with increased speed and range.

SETTING OF FAT TORPEDOES

        F.A.T. torpedoes in tubes were on setting Right Long, 14,000 meters.  U-231 never fired and F.A.T. torpedoes.

INSTRUCTION ON F.A.T. AND T-5 TORPEDOES

        Torpedo-room personnel on U-231 were not aquatinted with this torpedo, nor with T-6.  Instruction given the torpedo petty officer of U-231 was sketchier than has been the case with other U-boats.  His F.A.T. instruction was confined to a short lecture by the flotilla torpedoman at La Pallice, probably in June 1943.  Instruction consisted only of servicing and setting and included no details of track except the a brief description of "Curly" course run by F.A.T-1.  His instruction in T-5 took place in Gotenhafen in July 1943.  He did not, unfortunately, take the whole course.  He attended two morning lectures on care and servicing of T-5, but was never present at firing trials.  He was shown no models, drawings, nor sketches of the torpedo's track.  He never saw nor made a Spatz test.  His knowledge was, therefore, considerably less extensive than that of any other torpedo petty officer recently interrogated.

TESTS OF COMBINATION PISTOLS

        All pistols carried by U-231 on her second and third patrols had combination impact-magnetic firing.  The magnetic apparatus was tested by the flotilla torpedoman in La Pallice

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before the start of each patrol.  No further test was ever made on board.

NEW TYPE OF MACHINE GUN

        One prisoner mentioned a new type of 15 mm. machine gun, said to have a theoretical rate of fire of 1,000 rounds per minute.  Whether and, if so, when this new type would replace the demountable machine guns now carried by U-boats could not be ascertained.

NEW 20 MM. AMMUNITION

        The new type of 20 mm. ammunition is known as "Ölbrandmunition (Oil incendiary ammunition).  U-231 may have carried this new type among other types on her last patrol.

        It was described as armor-piercing and explodes as an incendiary thereafter.  It has a pointed nose, has tracers up to 2,000 meters, and is self-destroying at 2,500 meters.  The prisoner who saw experiments at Mimizan described the explosion, after piercing the armor, as a flash of vivid orange flame.

NEW U-BOAT ARMAMENT

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        (d)  One 6-barrelled rocket projector aft on the bridge.  This device was claimed to be capable of firing in any direction.  The rockets are said to be inserted from the top and are electrically fired.  Coxswains and boatswains are now being trained to operate rocket projectors.

        (e)  Usual demountable machine guns on the bridge.

REMOTE CONTROL FIRING

        A radioman stated that he had never heard of remote control firing on U-boats.  He doubted very much whether any such developments are contemplated.

REMARKS ON G.S.R.

        (a)  Wanz G-2.  Covers a wave band from 120 cm. to 180 cm.  It is identical with Wanz G-1 except that radiation had been eliminated; consequently no telegraph key such as was fitted on U-841 was needed.  (See G/Serial 28).  Wanz G-2 is fully described in G/Serial 29 on the interrogation of survivors from U-172.  One of the radioman of U-231 stated that Wanz G-2 was a very delicate instrument and was easily put out of order.

        (b)  Naxos.  U-231 carried 2 Naxos sets.  Each set was used for three days at a time.  Two Naxos aerials of the usual type were carried.  The aerial had to be rotated continually while in service.  A wave band from 8 cm. to 12 cm. was covered; the practical range was said to be 15 kilometers.

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picked up by Borkum were heard through the Radione set.  The Borkum carried on U-231 was identical with the set carried by U-172 and is described fully in G/Serial 29.

G.S.R. SEARCH PROCEDURE

        Procedure on U-231 was to operate both Naxos and Wanz G-2 simultaneously.  If a signal was obtained on Wanz G-2, Borkum was connected to the drum-shaped aerial in place of Wanz G-2.  If a tone was then heard on the Radione set, Borkum was disconnected from the aerial again.  If the tone was then still heard on the Radione it was proof that the signal was being received by the Naxos set which remained connected to the Radione set.  Of course, if a tone had been heard on the Radione set in the first place, i.e., before the Borkum was connected to the drum-shaped aerial, this was an indication that Wanz G-2 had picked up the signal.

        It seems definite that German U-boats attach the greatest importance to the continuous observation of the 10 cm. wavelength.

NEW LORENZ H/F D/F SET

        A new H/F D/F set manufactured by Lorenz was installed on U-231 prior to her last patrol.  The set was referred to as "Zwischenfrequenzpeiler".  It was mounted in the radio room in place of the former D/F set.  (See No. 4, Plate I).  This set, as well as the long wave D/F apparatus, is supplied by one power pack, and either set could be supplied by simply throwing the switch.  The plate current for the H/F D/F is 5 to 7 volts.  The actual upper limit of the frequency covered by this set was not established, but

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the primary purpose was to D/F voice traffic on 124 meter wavelength.  It was believed, however, that the range below 124 meters was greater than that above 124 meters.  U-231 had no opportunity to use this set on her last patrol.

        In order to use the D/F loop for the new set, the windings in the loop were changed.  A radioman was under the impression that all but two of the windings were removed.  A special, radiating rod aerial ("Strahler", see also Plate VII, page 25, G/Serial 27), to serve as compensator for the D/F loop was mounted forward on the bridge.  The forward jumping wire aerial is used as compensator for the L/F D/F set.

NEW RADAR EQUIPMENT

        A radioman stated that, in the future, U-boats will be equipped with "Hohentwiel" radar sets.  This type was formerly used by G.A.F. and is being adapted for use in U-boats.  The set was said to operate on a wavelength of 50 cm.  In addition to the mattress type aerial, U-boats carrying "Hohentwiel" radar will also carry a drum-shaped aerial mounted on an extensible rod, thus permitting all-round search at periscope depth.  The dipoles of the drum-shaped aerial are believed to be shorter than those used on the drum-shaped G.S.R. aerial.  It was believed that U-boats equipped with "Hohentwiel" radar would no longer carry any G.S.R. gear whatsoever.

MULTI-UNIT HYDROPHONES

        The Multi-Unit Hydrophone set (G.H.G.) fitted on U-231

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had a dial which could be set to 0-500-1000-2000-3000.  It was stated that these settings affect the pitch of the tone heard.  Propeller sounds of destroyers were heard best in the 500 setting.  If the dial was set higher than 500 the sound became a high-pitched whine and was finally almost inaudible.

ARANGEMENTS OF RADIO AND LISTENING ROOMS

        The arrangements of the radio and listening rooms aboard U-231 are shown in plates I to V.

NEW ARRANGEMENTS OF RADIO AND LISTENING ROOMS

        It was stated that as of February 1944 the radio and listening rooms aboard U-boats will be rebuilt and rearranged.  New equipment, including a depth charge plotter and counter, will be added.

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CHAPTER IV.  TACTICAL REMARKS

ANTI-AIRCRAFT TACTICS

        It was stated that U-boats will not dive when an airplane has approached closer than 8,000 meters.  The officer on the bridge is responsible for estimating the distance and deciding whether the boat will dive or will fight it out on the surface.  Prisoners confirm that U-boats are in particular danger from A/C just after they have dived even though the U-boat makes an immediate turn to port or starboard.

U-BOAT AND A/C COOPERATION

        When U-231 was on her last patrol, operating in the group of U-boats stretched from Cape Finisterre to the Azores, she was instructed by Control to listen for A/C beacons for 3 days at 0800 and 2000.  The transmissions were said to be on a frequency of 385 kilocycles.  U-231's approximate position was 42 N. - 15 W.

        It was claimed that it is now the practice of U-boat patrol lines, operating in cooperation with German aircraft, to remain submerged almost continually.  The spacing between the U-boats was said to be about 20 miles.  Aircraft search for an expected convoy and, upon sighting, report to Control.  U-boats are required to listen at stated intervals (Programmzeiten) to transmissions from Control, either at periscope depth or upon coming to the surface.  They may then receive instructions either to proceed to a given position or to listen for aircraft beacon signals.

        Since experience has shown that positions given by A/C are known to be unreliable, Control will then generally instruct

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the A/C to transmit a beacon signal.  Thereupon each U-boat reports the bearing on which she has heard the A/C beacon, together with her own position.  From the information Control plots the exact position of the A/C (i.e. the Convoy) and issues the necessary orders to the U-boats which are to participate in the attack.

        Simultaneous attacks of U-boats and A/C against convoys have not been heard of by prisoners.

PASSAGE REPORT

        When passing 20⁰ W.  U-boats must report to Control.  Formerly this passage report was made at 15⁰ W.  Only if a U-boat has just previously been called to report position and stock of fuel on hand, may the passage report be omitted.

RADIO INTELLIGENCE ON U-BOATS

        A radioman stated that the practice of adding radio intelligence operatives to U-boat crews has been discontinued.  Experience had shown that the intercepted voice traffic was of relatively little value.  It is deemed more important to D/F these transmissions disregarding the contents of the transmission.  It is felt that the purpose of D/F'ing is amply served by the installation of the new H/F D/F Lorenz set, described in Chapter III.

U-BOATS IN THE BALTIC

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U-boats were said to have been kept in the Baltic.  The only reason advanced for this accumulation of boats was that the boats were waiting for new equipment such as the Wanz G-2 G.S.R. set and the new automatic 37 mm. gun.

ESCORT MEETING POINT

        U-boats entering or leaving La Pallice have an escort of a mine destructor vessel from or to a point identified as "Punkt Gabel".  This was stated to be on the 50 meter line.  It may serve more than one base and probably included the Bordeaux base.  A radioman was under the impression that the name of the meeting place would be changed frequently.

REPLACEMENT OF QUADRUPLE 20 MM. MOUNTS.

        It was stated that in the future all U-boats on operational patrol will be fitted with the new automatic 37 mm. gun instead of the 20 mm. quadruple mount.  The latter had proved unsatisfactory as the training and elevating mechanism was easily damaged by the corrosive action of sea water.

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CHAPTER V.  CREW OF U-231

TOTAL COMPLEMENT

        U-231 had a total crew of 50 on her last patrol.  This included the captain, 2 line officers, one engineer officer, one doctor, 15 petty officers, and 30 enlisted men.  Two petty officers and 5 enlisted men did not survive the sinking.

OFFICERS

        With the exception of the doctor the officers on U-231 had been with the boat since her commissioning on 14 November 1942.  The doctor took part on the second and the last patrol only.

        Kapitänleutnant Wolfgang Wenzel, of the 1934 German Naval Term, was definitely not the usual type of German U-boat commander encountered by his interviewers.  Apart from being 100% Nazi, stubborn and stupid in his political philosophy, he was highly nervous and confirmed the opinion which most of the crew and his officers had, namely that he was a coward, unfit for the dangerous task of commanding a U-boat.  Almost all prisoners were unanimous in their opinion that U-231 could at least have made an attempt to return to base after she had been attacked on 13 January 1944.  Whether this would have been the wise course is doubtful, but the crew's opinion was based on their previous experiences with Wenzel.  On both previous patrols Wenzel violated the oft-repeated instructions of Grand Admiral Dönitz always to attack.  He had submerged upon sighting ships or convoys giving as his reasons that such encounters were dangerous, due to air cover or to superior escort

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protection.  On three patrols U-231 only fired one torpedo; this was on the day before she was sunk.  The torpedo, aimed at what was believed to have been a destroyer, missed, but an explosion, as yet unexplained, was cited by Wenzel as the proof of a probable hit.

        Prior to entering the Navy in 1934, Wenzel was said to have belonged to the merchant marine for several years.  He is now 34 years old, three or four years older than his classmates.  His history is not well established.  He served as communications officer on Raider 16 which was sunk on 22 November 1941 by H.M.S. DEVONSHIRE.  Wenzel was rescued by a group of U-boats and was probably taken aboard an Italian submarine.  (O.N.I. Note:  This was probably the CALVI commanded by C.d.C. Emillio Olivieri.)  Upon his return to Germany, he volunteered for the U-boat arm.  On another U-boat he made one or two patrols as commander-under-instruction.

        When U-231 was sinking, Wenzel attempted suicide by shooting himself in the mouth.  Unsuccessful as always, he was not able to do away with himself.  The bullet lodged in the back of the neck and was extracted several days later on U.S.S. BLOCK ISLAND.  Few of the crew knew about the suicide attempt as he explained to his shipwrecked companions, while on the raft, that he only suffered from a sore throat.  He did not like to be reminded of it once he was ashore.

        The executive officer was an Austrian, Oberleutnant z. S. Friedrich von Schiefner, of the December 1939 Term.  He was

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23 years old.  His history is not known.  He was reasonably well liked by the crew.  His political beliefs were not necessarily  those of his captain, but he was an ardent advocate of a Greater Germany.

        Leutnant z. S. Joachim Hünefeldt, 21 years old, was second watch officer.  He belonged to the October 1940 Term.  Politically he was violently anti-Nazi, but sufficiently indoctrinated to remain adamantly security-conscious.  The third patrol of U-231 was Hunefeldt's sixth on U-boats.  He had previously served as midshipman on U-751 under Kapitänleutnant Bigalk; the three patrols on that boat had taken him to the East Coast of the U.S. in the heyday of U-boat warfare early in 1942.

        The engineer officer aboard U-231 was Oberleutnant (Ing.) Christoph Geyer, 26 years old, of the October 1939 Term.  U-231 was his first operational U-boat as he had previously only served on school boats.  The few times he was called upon to perform more than routine duties, he acquitted himself well.  The commander must have appreciated this as Geyer was awarded both the Iron Cross 1st and 2nd class after completion of the first patrol.

        Dr. Willi Reinhard, Stabsarzt d. R., was the medical officer aboard U-231.  He was born in 1909.  This was his second patrol since he joined U-231 after her first patrol.  Before being drafted to the Navy, he specialized in pediatrics after having attended the universities of Freiburg and Vienna.  Reinhard was not a full-fledged Nazi and on some occasions even voiced outspoken anti-Nazi sentiments, which were apparently not well received by

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Wenzel.  He was not sure why a U-boat carried a doctor as he only once had occasion to make use of his profession.  This was when three men from another U-boat were rescued in the North Atlantic in October 1943.

PETTY OFFICERS

        Among the petty officers the chief quartermaster, Albert Borck, 31 years old, was outstanding from a point of service.  He had made a total of 15 patrols, although U-231's last patrol was his first patrol on her.  Previously he had served with Kapitänleutnant Guggenberger on U-81.  He had been decorated with the German Cross in Gold.  He was pleasant but extremely security conscious.

        It was again confirmed that among a U-boat's crew this group of men has by far the most to offer and several of them responded well to the efforts of the interrogators.  Among them in particular Wenzel was disliked and distrusted. 

        The average age of this group was 24-1/2 years.

ENLISTED MEN

        Few groups of U-boat prisoners have been encountered on this side of the Atlantic with as low an I.Q. as this crew.  The average age was 21 years.  Their stupidity was only surpassed by their desire to keep whatever little they knew hidden from the interrogators.  Only Goebbels' teachings were well known and willingly spouted at the least provocation.

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CHAPTER VI.  EARLY HISTORY OF U-231

COMMISSIONING

        U-231 was commissioned 14 November 1942.  A small celebration was held at which the commander of the 5th Flotilla, Korvettenkapitän Möhle and the father of U-231's commander were present.

U.A.K. TRIALS

        U-231 was attached to the 5th Flotilla and began her U.A.K. trials in her home port Monday, 16 November 1942.  Nothing unusual happened during the acceptance trials except that a short trip to Rendsburg was taken for the purpose of conducting some listening tests.

T.E.K. EXERCISES AT GOTENHAFEN

        Upon completion of the U.A.K. trials U-231 was ordered to report to the 8th Flotilla at Danzig to which she, however, was not formally attached.  On the way, she stopped over briefly at Sassnitz, then conducted her speed trials from Sassnitz to Rönne.  The usual listening tests were conducted at Rönne, from which she reached Danzig 17 December 1942.  Several days later U-231 was sent to Gotenhafen to start the T.E.K. exercises, but after a few days the exercises were ended prematurely to allow U-231's crew to return to Danzig for the Christmas holidays.  Except for the crew members who lived nearby, none of the crew were given leave, although Wenzel spent the holidays with his wife at Kiel.

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        Shortly after Christmas U-231 returned to Gotenhafen to complete the T.E.K. exercises on New Year's Eve.

"AGRUFRONT" AT HELA

        On 1 January 1943 U-231 left for Hela to begin the exercises conducted by the Active Service Group (Agrufront).  About 20 other U-boats were present during the exercises which ended 4 or 5 February 1943.  At some time during her stay at Hela U-231 was used to train a group of engineer officers under instruction.

TORPEDO FIRING AT DANZIG

        U-231 arrived at Danzig 6 February to start a week's torpedo firing practice.  The crew was not too well impressed with their commander's shooting, but claimed that their executive officer did very well.

TACTICAL EXERCISES

        Having finished torpedo firing practice 13 February 1943, U-231 joined a group of about 12 U-boats at Gotenhafen 15 February to start her tactical exercises which lasted until 27 February.  Among the U-boats present were U-232 and U-533.  (See also Chapter XI.)  Surface ships participating were the depot ships KOPHAMMEL, SEEBURG, WILHELM BAUER, the U-boat tender SAAR; also VEGA.

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Blaming it on the commander, he told Wenzel:  "You'll have to repeat the tactical exercises; if you take your boat on patrol now, your entire crew will be on your conscience".  On 17 February 1943 U-231 was ordered to undergo her final overhaul after which she was to come back for another try at the tactical exercises.

FINAL OVERHAUL

        On 1 March 1943 work was begun at the Germania Werft, Kiel, on the final overhaul.  Only minor adjustments were necessary.

REPETITION OF TACTICAL EXERCISES

        End of March 1943 U-231 joined a group of U-boats off Bornholm to make good the convoy exercises which had been unsatisfactory the first time.  Early April she returned to Kiel to be fitted out for her first patrol.

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CHAPTER VII.  FIRST PATROL OF U-231

DEPARTURE FROM KIEL

        U-231 left Kiel 13 April 1943 in company with U-531, commanded by Kapitänleutnant Herbert Neckel, and another 750-ton U-boat commanded by Kapitan Werner Happe.  A small patrol ship supplied the escort until Kristiansand was reached.  U-231 remained there only for a few hours, then shaped course for the North Atlantic.  It was discovered that all frequency series tables were left behind, except the "Kustenschaltung" (coastal frequency).  Control had to send about 35/40 messages to give U-231 all the required frequencies.

PASSAGE THROUGH THE "ROSENGARTEN"

        From KristiansandU-231 reached the North Atlantic through the "Rosengarten".  The passage was uneventful.

ATTACK BY AIRPLANE 21 APRIL 1943

        About noon 21 April 1943 U-231 was attacked by an aircraft believed to be a Sunderland; no damage was sustained and U-231 dived immediately.  (O.N.I. Note:  This may have been the attack delivered by a Catalina at 1320 GCT 21 April 1943, in position 63.45 N. - 09.15 W.)

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tower hatch when he observed the cable from the G.S.R. aerial, which had not been taken down.  As the hatches could not be closed with the cable hanging down, he went up on the bridge in an attempt to unfasten the aerial.  By that time the bridge was already under water.  One of the ratings slammed down the hatch as tightly as possible and stood on top of the hatch leading into the control room.  Water came pouring into the boat, accumulating mainly in the forward part.  At 40 meters she was leveled off and broke surface shortly thereafter.  The Chief Quartermaster had been swept away, and Wenzel, seeing the airplane drop bombs, ordered the boat to submerge again after a rating had dislodged the G.S.R. aerial.  U-231 remained submerged for about 2 hours, and upon reaching the surface the commander made a search for his lost quartermaster.  It was only a gesture and recognized as such by the crew.  (O.N.I. Note:  The attack was probably delivered by a Catalina which dropped bombs on a surfaced U-boat at 0305 GCT 22 April 1943 in position 62.38 N. - 11.44 W.)

THIRD AIRPLANE ATTACK 23 APRIL 1943

        At about 1230 23 April 1943, an airplane believed to have been a Sunderland dropped one or more bombs near U-231.  One of them was thought to have exploded about five meters from the boat, but no damage was sustained.  Before U-231 dived, several rounds were fired at the airplane by the boat's 20 mm. cannon; however, ammunition was not passed quickly enough and firing ceased.  (O.N.I. Note:  It has not been possible to identify this attack.)

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FIRST OPERATIONAL AREA

        U-231 spent some time now in the Western Approaches where she may have belonged to group "RAUBRITTER", which was said to have consisted of 27 U-boats.  (O.N.I. Note:  Groups "MARKGRAF", "RAUBTIER", "RAUBVOGEI", and "RAUBITTER" have been mentioned as operating from late January to March 1943.)  No ships were sighted by U-231 nor was she attacked in this area.

SECOND OPERATING AREA

        The U-boat then was ordered northward and probably operated in an area northeast of Newfoundland where she may have been a member of group "SPECHT".  Later she joined another group of U-boats believed to have been "ELBE".  Among the U-boats present in the various groups were U-107, U-221, U-404, U-504, U-531 and U-533; also U-boats commanded by Kapitänleutnant Claus v. Trotha, Kapitänleutnant Karljürg Wächter, Kapitänleutnant Heinz Franke, and Kapitänleutnant Horst Uphoff.

        Although several convoys were reported to U-231, she never sighted but one.  This consisted of 3 or 4 larger ships.  Wenzel, always considerate of his boat's safety, gave the order to dive.  He did not report the sighting to Control.  U-231's executive officer threatened to make Wenzel's attitude known upon return but apparently never bothered to bring it up, once he was back at the base.

U-231 IS SUPPLIED

        About mid-May 1943 U-231 was ordered to meet U-504 and

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U-107 both of which were on their way home but could spare some fuel oil.  From U-504 28 tons of fuel oil were taken over.  The rubber boat which was loaded with food capsized.  After oil had been taken over from one of the boats, the process was repeated with the other.  The position of the meeting was estimated at about 45⁰ N. - 40⁰ W.

ATTACK BY CARRIER-BASED PLANE

        After this meeting U-231 turned north, and nothing happened for a few days to disturb the quiet pursuit of the patrol.  She may have rejoined group "ELBE".

        On 21 May 1943 at 0100, however, U-231 was surprised by an airplane believed to have been carrier-based.  Only one bomb was dropped but, aimed with splendid accuracy, it exploded close to the conning tower.  The stern trimming tank was ruptured and water started to leak into the boat; some of it reached the after battery which started to develop chlorine gas.  It was possible, however, to control the damage although the danger of a battery explosion remained for some time.  (O.N.I. Note:  This may have been an attack delivered by an airplane from U.S.S. BOGUE at 2113, 21 May 1943 in position 52.00 N. - 35.25 W.)

SIGHTING OF CONVOY AND ATTACK BY ESCORT

        Hardly had the necessary emergency repairs been made when a convoy was sighted.  Following his natural inclination, as well as taking into account the maneuvering his boat, Wenzel made off on the surface but was forced to submerge.

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The pursuing ship dropped one depth charge which landed far off and did not add to the damage already sustained in the airplane attack.

MEETING WITH U-459

        U-231 reported the extent of her damage and was ordered to rendezvous with U-459, under command of Kapitänleutnant Wilamowitz-Möllendorf.  The meeting took place 24 May 1943.  No fuel was supplied to U-231 as she was not to continue her patrol.  Two cross-type G.S.R. aerials were transferred, and a radioman was sent aboard U-231 to attempt to repair the damage to some of the radio equipment.  He was unable, however, to do it, quite to the delight of U-231's radiomen.

RETURN TO LA PALLICE

        U-231 returned from her first patrol 30 May 1943 and was immediately dry-docked at her base, La Pallice.  She was now attached to the 3rd Flotilla.  No torpedoes had been fired on this patrol.

REPAIRS AND ALTERATIONS

        After repairs had been completed, U-231 was fitted with the new armored bridge, Platform I, and Platform II.  Her 88 mm. deck gun was removed, and two single 20 mm. cannons were fitted on Platform I, a quadruple mount 20 mm. on Platform II.  It was believed that U-231 was one of the first, if not the first, U-boat to be so equipped at the La Pallice base.  New batteries were

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installed as the original set was damaged by the attack on 21 May.  By the end of July 1943 she was ready to leave on her next patrol.

FIRST ATTEMPTED DEPARTURE

        U-231 left La Pallice 27 July 1943; she was escorted by a torpedo boat and probably by a minesweeper.  Some distance out, she was joined by U-504, a supply U-boat, and an unidentified U-boat from Bordeaux.  The escort now totaled four torpedo boats, one of which was JAGUAR, and one or two minesweepers.  (O.N.I. Note:  The supply U-boat was probably U-461, leaving on her last patrol.  See C.B. 04051(81), Chapter III.  The other U-boat could have been U-462; see C.B. 04051(82), Chapter III.)

        At the 200 meter line all boats undertook the customary diving trials during the course of which water started to leak into U-231 through the Diesel exhaust valves and the stern torpedo tube.  Wenzel, never a man to take a chance, ordered an immediate return to base.  His request to do so was radioed to Control, but a reply was not awaited.  JAGUAR was detailed to take U-231 back to port.  On the way a mine destructor vessel was added to the escort.

U-231 IS DAMAGED BY A MINE EXPLOSION

        When U-231 was only about two hours from La Pallice, a mine exploded about two meters from the boat causing considerable but not fatal, damage.  The foundations of the electric motors were displaced, some converters torn off, the batteries were damaged, a

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diving tank ruptured, and the new quadruple mount put out of commission.  Fuel oil was found in the ammunition chamber.  At first it was thought that U-231 would have to be towed into port by JAGUAR, but later it was found that she could move under her own power.  She was unable to dive.  La Pallice was reached the morning of 29 July 1943.

FURTHER REPAIRS AT LA PALLICE

        U-231 went into dry dock immediately upon arrival and remained there until the end of August when she moved into a wet bunker.  She was now ordered to await the new G.S.R. set, Wanz G-1.

DRAINING OF BASIN AT LA PALLICE

        In an Allied air raid, several tugs, an oiler, and a crane had been sunk and a floating dock and a mine destructor vessel badly damaged.  The port authorities decided to drain the basin, thus making it necessary for all ships not in dry bunkers to leave the harbor.  The draining was set to start at 0800 10 September 1043.  U-231 left the wet bunker at 0600 7 September 1943 and after a short stop in the outer harbor proceeded to Bordeaux where she arrived the following day.

FIRST START FROM BORDEAUX

        The Wanz G-1 set arrived on 22 September 1943, so U-231 was ordered to sail the following day.  She left Bordeaux late 23 September and although ordered to heave to at the mouth of the Grionde, U-231 sailed on because a stop there could possibly be

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construed as the real departure for their second patrol - and by that time it was Friday.

RETURN TO BORDEAUX

        U-231 made the customary deep diving trial at the 200 meter line and again water seeped into the boat through the exhaust valves and also through the lead-in of the G.S.R. aerial into the radio compartment.  Wenzel, always intent on Safety First, decided to return to Bordeaux.  On the way in she met up with a U-boat commanded by Kapitan Werner Hartmenn; both boats arrived as Bordeaux the afternoon of 24 September 1943.

        Repairs were made, and by Monday, 27 September U-231 was ready to leave on her long-delayed second patrol.

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CHAPTER VIII.  SECOND PATROL OF U-231

DEPARTURE

       U-231 sailed from Bordeaux 27 September 1943.  Her Diesels gave some trouble, but the engine room personnel were able to make the necessary repairs, and U-231 continued on her course to the operational area first assigned to her, namely, the Western Approaches.

JOINING WITH GROUP "LEUTHEN"

        Early in October 1943 U-231 was a member of group "LEUTHEN" which, among others included U-455, U-270, U-450, U-402; also U-boats commanded by Kapitänleutnant Erich Mäder and Kapitänleutnant Horst Hepp.  U-455 was rammed by another U-boat and had to return to port.  U-231 sighted and attacked nothing while with this group.

OPERATING OFF GREENLAND

        U-231 then proceeded north and joined group "ROSSBACH" operating off Greenland.  Again, she was unsuccessful in locating or intercepting any convoys and, therefore, turned south.

RESCUE OF MEN FROM U-HUMMERJOHANN

        A few days later U-231 surfaced at dusk after having been forced to dive by the presence of some aircraft.  The bridge watch observed some men swimming in the water and from their cries for help they were identified as Germans.  These turned out to be crew members of a U-boat commanded by Oberleutnant z.S. Hummerjohann which had just been sunk by an airplane.  Five men were taken

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aboard U-231 under great difficulties, among them Hummerjohann.  He was already dead, however, and was therefore, returned to the sea after his identification tag had been removed.  Of the other four men, a torpedo rating died shortly after the rescue and was buried at sea.  The three men who were kept alive were two firemen and a seaman.

        Hummerjohann had been able to signal the attack to Control which was advised of the imminent sinking.  (O.N.I. Note:  This was probably U-964 which according to G/Serial 28 was believed sunk on 1 October 1943 by aircraft and from which four men were claimed rescued by another U-boat.  The attack was delivered 17 October 1943 in position 58.38 N. - 31.56 W., by Liberator "D" of 59 Squadron and Liberator "H" of 120 Squadron, both engaged in A/S patrol in vicinity of convoys O.N. 206 and O.N.S. 20.  "D" dropped 4 Mark XI torpex depth charges on her first run; "H", after an unsuccessful first run, dropped four similar charges.  "D" then dropped four additional charges, immediately followed by "H" which dropped the last four charges.  The U-boat broke in two, survivors and bodies were seen in the water.  The U-boat was first sighted at 1817A., the sinking occurred about 1826; "H" finally departed at 1838.  The attack has been assessed "Known sunk".

        Considering the proximity of U-231 to the sinking position of U-964 and U-841 (See G/Serial 28), it is believed that U-231 also belonged to group "SCHLIEFFEN" which operated against convoy O.N.S. 20).

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CONTINUATION OF PATROL

        U-231 continued her patrol, but as her commander was not particularly anxious to risk his own and perhaps his crew's life, he never sighted any shipping nor was U-231 attacked.

        While U-231 was on the latter part of her patrol, she was scheduled to meet a supply U-boat.  A signal from Control was received:  "Supply cannot be undertaken; U-boats are on their own.  Attack the enemy - the Fatherland is watching you".  Needless to say, the message was not well received, and reference was made to the "usual Dönitz bunk".

RETURN TO LA PALLICE

        U-231 returned to La Pallice 22 November 1943, just eight weeks after leaving Bordeaux.  All torpedoes were brought back.  A delegation headed by Wenzel immediately departed for St. Nazaire to attend a "pep" meeting presided over by Grand Admiral Dönitz.  This took place 25 November at La Baule, and it was also here that some of the petty officers, as well as the doctor, were awarded the EK-2.  All returned to La Pallice Saturday, 27 November 1943.

PPREPARATIONS FOR THIRD PATROL

        Sometime during the course of the second patrol U-231 had received a message from control requesting performance records of the 20 mm. quadruple mount.  U-231 had nothing to offer since even as practice firing was prevented by heavy seas.  Upon return from the patrol, however, U-231 was fitted with on e of the two new

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automatic 37 mm. guns available at La Pallice at that time.  The 20 mm. quadruple mount had not proved satisfactory on other boats.  The new gun was installed on Platform II; on Platform I, 2 twin 20 mm. cannons were fitted.  After sundry other small changes, such as the replacement of G.S.R. set Wanz G-1 set by Wanz G-2, U-231 was ready to leave on her third patrol 26 December 1943.

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CHAPTER IX.  THIRD AND LAST PATROL OF U-231

DEPARTURE

        U-231 left La Pallice 26 December 1943 with at least 4 other U-boats said to have been commanded by Oberleutnant Wolfgang Rahn, Oberleutnant Gustav Lüssow, Oberleutnant Detlev v. Lehsten, and Oberleutnant d. R. Perre, believed to command U-645.  Other U-boats mentioned but not confirmed as being part of the group which left together 26 December 1943 were U-600 and U-953.  (O.N.I. Note:  It is possible that Rahn, Lüssow or v. Lehsten commanded U-600.)  The group was escorted by a mine destructor vessel and several minesweepers.

DEEP DIVING TRIALS

        U-231 finished the deep diving trials first, and even though the Diesel exhaust valves, as usual, were leaking, Wenzel decided that he could risk continuing the patrol.  U-600 and U-645 may have returned to port to effect slight repairs.

JOINING WITH GROUP OFF SPAIN

        The passage through the Bay of Biscay was made submerged by day and surfaced by night.  Probably at the turn of the year U-231 joined a group of 9 U-boats which operated between Cape Finisterre and the Azores; she took a station nearest the Spanish coast.  This group, which by some prisoners was called a :Destroyer Group", included U-618, U-645, U-952, U-953 and a U-boat commanded by Borck.

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CANCELLING OF AIR SUPPORT

        Some time during the early days of January 1944 the U-boats in this group were advised by Control that the promised support of airplanes would not be available.  The reaction on board U-231 was similar to that given the message U-231 had received on her second patrol when meetings with supply U-boats were cancelled:  "The usual "Dönitz bunk" - and this was only one of the more polite ways of expressing what everyone felt.

HUNT BY A DESTROYER

        At about the same time U-231 was hunted by a destroyer.  No depth charges were dropped, but detonations thought to have originated from a new type of search gear were heard.  The prisoners referred to this as "Knalloten".

        While belonging to the Group, U-231 was never attacked by aircraft, through a total of 9 radar contacts were intercepted on the G.S.R.

U-BOATS SUNK

        It was believed that at least 2 if not 3 U-boats of this group were sunk before the group was dissolved 11 January 1944.  One of these was said to have been sunk 20 miles, the other 50 miles away from U-231.  The position of U-231 on 10 January 1944 was 41.28 N. - 17.17 W.

U-231 FIRES HER FIRST - AND LAST - TORPEDO

        U-231 proceeded westwards after the dissolution of the

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group.  On 12 January 1944, toward evening, propeller noises were heard, and when the periscope was raised, Wenzel claimed to have seen a destroyer approaching them on a zigzag course.  Mustering more courage than he had displayed on other occasions, but changing his mind several times he ordered a torpedo fired.  Tube 2, containing a T-5 torpedo, was made ready; the depth setting was 4 meters, distance to target 5,000 meters.  As soon as the torpedo was fired, U-231 went to a somewhat greater depth.  No explosion was heard within the 9 minutes which was the running time of the torpedo.  Twelve minutes after firing, however, and explosion was heard, and by many it was assumed that U-231 finally had achieved her first success.  About half an hour later, Wenzel gave the order to surface.  Nothing was in sight and many of the crew, encouraged by remarks of the commander, assumed that this was another case of "spurlos versenkt".  The morale of U-231's crew was bolstered effectively as it was believed that now they belonged to the select group of boats which had sunk an Allied destroyer.  (O.N.I. Note:  No Allied destroyer or escort vessel of any type was sunk 12 January 1944.)

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CHAPTER X.  SINKING OF U-231

U-231 IS SURPRISED BY ATTACKING AIRPLANE

        U-231 was proceeding surfaced the night of 13 January 1944 and charging her batteries.  The Second Watch Officer had the bridge watch.  Her G.S.R. set was manned. the cloud cover was low, but diffused moonlight improved the visibility.  Nobody on the bridge saw or heard the big bomber until it was practically on top of them.

        Two bomb explosions were seen and felt.  One bomb fell to port about 15 meters from the boat, the other dropped to starboard about 2 meters away.  Machine gun fire from the airplane hit the U-boat, and bullets were said to have penetrated into the forward torpedo compartment.

        Wenzel, who was in the conning tower at the time of the explosions, rushed up to the bridge to direct the action.  All anti-aircraft guns were ordered manned, the ready-ammunition lockers for the 37 mm. automatic gun were opened, and the gun was loaded with about 10 shells.  It was found however, that the concussions, or a direct hit, had jammed the training mechanism, thus eliminating the gun from active participation in the duel.

DAMAGE

        The immediate results of the bombing were damages to the boat's electrical equipment, due mainly to the burning of the main switchboard.  The fire was brought under control slowly by the use

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of foam extinguishers.  A radioman tried to transmit a signal reporting the aircraft attack, but found that no current was available.  Some time later current for transmitting was restored, but current for receivers failed.  Survivors doubt whether the message of the attack was ever received by Control as otherwise U-boats in the vicinity might have been detailed to pick them up.

        It was also reported to the commanded that water was entering the boat through the flanges of the stern torpedo tube.  It was not, however, evident how serious this leak would become.

SECOND ATTACK BY BOMBER

        Returning for a second attack, the airplane dropped several more bombs, but this time both twin 20 mm. mounts were ready, and 80 rounds of 20 mm. ammunition were fired.  Hits on the airplane were observed.  It was believed that a motor was burning, and some, hopefully, thought that the airplane would not reach its base.

U-231 SUBMERGES

        Wenzel now inquired from his engineer officer whether the U-boat was able to dive.  Receiving an affirmative answer, he gave the order to submerge but was soon to regret it.  Due in part to the fact that an increased amount of water entered through the stern torpedo tube flange and in part to the damage inflicted on the vents as well as on the pumps, U-231 grew more and more heavy by the stern.  The electric motors were turning over only very slowly, hardly able to hold the boat which by now had assumed an angle of about 70⁰.  The order to surface was given, but No. 1 diving tank could not be closed.  Finally, No. 3 main ballast tank was blown, and U-231, which had submerged

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to about 50 meters, slowly reached the surface.

U-231 IS ABANDONED; WENZEL ATTEMPTS SUICIDE

        Wenzel gave the order to abandon ship and immediately one-man rafts were passed up through the conning tower and crew members started to jump overboard.  Some of the newer members of the crew who had become panicky when the boat was almost perpendicular while submerged, did not take time to put on life vests; furthermore some of the rafts proved faulty and sabotage was blamed for the omission of certain parts of the inflating mechanism.

        Sometime during the abandoning of his boat, Wenzel, probably in a fit of despondence, attempted suicide by firing a revolver bullet into his mouth.  The bullet lodged harmlessly, however, in the back of the neck, and most of the crew members were unaware of the event.

        The entire crew of U-231 escaped from the now sinking U-boat, taking to one-man rafts, as well as to an eight-man and 2 five-man rafts.  In addition, the "Marx" raft, which was stowed under the forward deck grating, was released.  Due to the failure of many of the one-man rafts, some crew members could not find room on the remaining rafts and seven men were lost by exposure or drowning.

U-231 SINKS

        Shortly after the boat was abandoned, she sank stern first.  It could not be ascertained whether the engineer officer

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found it necessary to open the valves, but it is believed that the various leaks were sufficient to sink the boat.  About 6 minutes after the bow had disappeared, the men in the water felt a terrific explosion which they attributed to the explosion of the batteries.

RESCUE OF SURVIVORS

        At first the rafts were kept together, and it was during this time that all men were given lectures on security, now that any rescue probably would mean falling into Allied hands.  It was at this time also that some criticism was voiced as to whether the boat could have been saved or not.  Most felt that it was given up too quickly.

        During the night some crew members claimed they saw a German Ju-90 fly over them and also observed a Liberator but neither airplane saw them.  The morning of 14 January 1944 a fighter plane was seen, and crew members speculated on the presence of an airplane carrier in the vicinity.  Two hours later several two-motored planes were seen and a little later two more.  All in all, 8 or 9 airplanes crossed the skies above the floating rafts, but apparently none saw them.

        About noon 2 airplanes were seen coming at them, flying low.  The survivors waved and used the Very pistol.  One of the planes dropped a smoke bomb and some dye markers.  One airplane continued circling until rescue was effected by two destroyers.  The survivors had split into 2 groups of rafts.

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ACTION REPORT

        The following is condensed from the action report of the attacking airplane, Wellington L/172:

        L/172 was on anti-submarine patrol ahead of convoy E.G.6 when a radar contact was made at a range of 10 miles.  At 2225Z a surfaced U-boat was sighted, distance 2-1/2 miles, course 360⁰, speed 6-7 knots, position 44.15 N. - 20.38 W.  Three Mark II torpex-filled depth charges were released from 60 feet, shallow setting, spaced 60 feet tracking across conning tower.  The first charge was observed exploding close to hull on port side, the third exploded about 80 feet to starboard of hull.  The second depth charge exploded with a brilliant flash, and it was believed that it had landed on the deck of the U-boat.  Front and rear guns were raking the U-boat's hull.  Thereafter 3 further runs were made, but clouds obscured and made attack inadvisable.  In final attack a pattern similar to the first was dropped, but explosions were not observed by the rear gunner as he was wounded by the U-boat's anti-aircraft fire.  The action was broken off and course set for base at 2255Z.

        The following is condensed from the report of U.S.S. BLOCK ISLAND.

        Two planes, while on anti-submarine patrol from U.S.S. BLOCK ISLAND, sighted eleven rafts at 1210 GCT, 14 January 1944.  From then on, orbit was maintained over the rafts until at 1403 U.S.S. PARROTT began picking up survivors, joined several minutes later by U.S.S. BULMER.  PARROTT picked up 26 survivors and BLUMER the remaining 17.  The position was 44.34 N. - 20.15 W.  At 1608 PARROTT transferred 6 prisoners by breeches buoy to U.S.S. BLOCK ISLAND; the tactical situation, however, required that the transfer be broken off, and it was not until 16 January 1944 that both ships effected the complete transfer of all prisoners to U.S.S. BLOCK ISLAND.

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CHAPTER XI.  OTHER U-BOATS

U-71	Commissioned summer 1940.  Her commander for the first three patrols was Korvettenkapitän Flachsenberg.  The engineer officer on the first patrol was Klt. (Ing.) Schultz, who was succeeded by Oberleutnant (Ing.) Stuerzinger of the October 1937 Term.
U-126	In May 1941 U-126 was damaged while surfacing under a depot ship, named either "SEEBURG" or "MEERBURG".  (O.N.I. Note:  This probably happened while U-126 was on tactical exercises in the Baltic.)  Subsequently, she went to Schichau Werft for repairs.
	U-126 left on her first patrol July 1941 and operated off Greenland together with U-431 and U-567.  On a later patrol, in November 1942, U-126 was refueled twice in the Caribbean.  In December she met U-172 and a U-boat commanded by Kapitänleutnant Helmut Witte.  The latter was supplied with two torpedoes.
	Until January 1943 U-126 was commanded by Kapitänleutnant Ernst Bauer, who had made a total of eleven patrols, seven in the South Atlantic, three in the North Atlantic, and one in the Arctic.  U-126 was believed sunk on her next patrol under a new commander.  (O.N.I. Note:  According to an unconfirmed report U-126 was lost in July 1943.)

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	Officers said to have served on U-126 include:  Oberleutnant Graf v. Balleström (not in G.N.L.); Oberleutnant Neubert (this may be Helmut Neubert of the October 1937 B term; a line officer named Prön and an engineer officer named Ulm (neither are listed in the G.N.L.).
	Kapitänleutnant Bauer was reported to have been awarded the Oak Leaves for having sunk 214,000 tons.
U-146	Before becoming a school boat at Gotenhafen, she made a patrol in June 1941 to the Shetlands under command of Kapitänleutnant Otto Ites.  (O.N.I. Note:  Apparently her one patrol was not made to Finland as had been previously reported.)
	U-146 has has the following commanders:
	Fall 1940 to late spring 1941, Kapitänleutnant Eberhard Hoffmann.  (O.N.I. Note:  Hoffmann was a casualty at the sinking of U-451 in December 1941.)
	Late spring 1941 to fall 1941, Oberleutnant Otto Ites.  (O.N.I. Note:  Prisoner at sinking of U-94, 27 August 1942.)
	Fall 1941 to April 1942, Oberleutnant Wilhelm Grimme.  (See below - U-boats Identified by Commander.)

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U-180 and U-195	Two 1200-ton U-boats were reported in Bordeaux in September 1943.  Both boats were originally equipped with Mercedes engines which, however, had not proved satisfactory and were being ripped out.  It was said that the crews had been transferred to other boats and that both boats, after being equipped with new engines, would undergo regular acceptance trials.  (O.N.I. Note:  It is known that these boats are U-180 and U-195.)
U-198	On 24 September 1943 a large U-boat commanded by Kapitan Werner Hartmann returned to the base at Bordeaux, together with U-231.  The patrol was said to have lasted 26 weeks.  It was believed that Hartmann left Bordeaux again early in December 1943 presumably for the Far East.  The executive officer on his boat was stated to be Oberleutnant von Georg.  (O.N.I. Note:  This is apparently Ritter Eberhard von Georg of the October 1940 Term.  Kapitan Hartmann is known to command U-198 and apparently was not sunk as previously reported.)
U-221	A U-boat commanded by Kapitänleutnant Hans Trojer belonged to Group "RAUBRITTER", "SPECHT", or "ELBE", which operated in the North Atlantic in April and early May 1943.  (O.N.I. Note:  Trojer is believed to have commanded U-221 which at one time was reported sunk in May or June 1943.)
U-229	Operated with U-231 in the North Atlantic mid-October

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	1943.  She was believed sunk in October 1943 while on her third patrol.
U-230	It was stated that U-230 was manned by the crew of U-612, which was rammed and sunk in the Baltic.  (O.N.I. Note:  U-612 was rammed by U-444 in May 1942.)
U-232	Commissioned soon after 14 November 1942 at the Germania Werft, Kiel.  Late June 1943 she was at Hela for exercises under the Active Service Training Group together with U-199 and U-231.  U-232 performed her tactical exercises together with U-231.  The exercises began 15 February 1943 and soon thereafter U-232 was rammed by another U-boat and had to undergo considerable repairs.
	U-232 was reported sunk by aircraft near Iceland but 11 men were reported survivors.  Previously she had been damage while passing through the Rosengarten.  The sinking probably took place soon after U-231 ended her first patrol 30 May 1943.  Her commanding officer was reported to be Kapitänleutnant Ernst Ziehm of the 1933 Term.
U-263	Reported to have been severely damaged in November 1942 and has been under repairs in La Pallice ever since.  Her commander was reported to be Kapitänleutnant Kurt Nölke of the 1935 Term.  Her officers, with the exception of the

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	commander, have been reassigned, but most of the crew are still in the personnel reserve at La Pallice.  The cover name of U-263 is said to be "Alma".
U-333	In the fall of 1943 a U-boat commanded by Kapitänleutnant Erich Cremer was reported to have rammed a corvette.  This was believed to have been the forth time that Cremer has rammed an escort vessel.
	An officer by the name of Tubinsky is Cremer's executive officer.  (O.N.I. Note:  Tubinsky apparently succeeded Leutnant Grumschied.  He is not listed in the G.N.L.)  The cover name of Cremer's boat is "Tummler".  (O.N.I. Note:  Cremer is known to command U-333)
U-402	A U-boat commanded by Kapitänleutnant von Forstner was believed sunk in October 1943 probably while operating in Group "LEUTHEN".  (O.N.I. Note:  An unconfirmed report states that U-402 was seen at La Pallice on 19 January 1944.)  While at La Pallice the cover name of this boat was "Bommel", not "Rommel" as previously reported.  (O.N.I. Note:  Kapitänleutnant Siegfried von Forstner is known to command U-402.)
U-404	A U-boat commanded by Korvettenkapitän von Bulow was a member of group "RAUBRITTER", "SPECHT", or "ELBE" in April and early May 1943.  (O.N.I. Note:  Von Bulow is known to command U-404.  He spoke on the radio early in May

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	1943 and has since relinquished command of U-404.)
U-431	Until January 1943 the commander of U-431 was Kapitänleutnant Wilhelm Dommes.  The insignia of U-431 is the coat of arms of Danzig.  (O.N.I. Note:  Also the word "Horrido".)
	U-431 left from Trondheim on her first patrol 8 July 1941 and participated in a convoy attack off Greenland together with U-567 and U-216.  Due to engine trouble she returned to St. Nazaire 12 August 1941, having scored no successes.  She left on her second patrol 13 September 1941 and returned 10 October 1941, claiming the sinking of a 5000 ton refrigerator ship.  On her third patrol she left 16 November 1941, passing through the Straits of Gibraltar into the Mediterranean, and after calling at Messina for fuel, operated off Alexandria.  The sinking of an 8000 ton tanker was claimed on this patrol from which she returned to La Spezia 20 December 1941.  U-431 was then attached to the 29th Flotilla.  She left La Spezia for her fourth patrol 2 January 1942.  She called at Messina for 3 days.  A 1200 ton escort vessel was claimed sunk off Malta, and U-431 then proceeded to operate of Tobruk together with U-375.  (O.N.I. Note:  U-375 under command of Kapitänleutnant Jürgen Könenkamp was sunk in the Mediterranean some time in 1943.)  On this patrol U-431 also claimed the sinking of a destroyer.  Before she

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	returned to La Spezia on 13 February 1942 she was attacked by a British submarine but escaped.  (O.N.I. Note:  According to a recent report U-431 was lost, probably late 1943.)
U-450	A U-boat commanded by Oberleutnant Kurt Bohme was a member of Group "LEUTHEN" fall 1943.  (O.N.I. Note:  Bohme is known to have commanded U-450 which has been reported sunk 30 October 1943.)
U-455	Kapitänleutnant Hans Martin Scheibe, former executive officer on U-431, commands U-455.  While operating in Group "LEUTHEN" early October 1943, she was rammed by an unidentified U-boat; one of her fuel oil tanks was torn and the 20 mm. quadruple mount went overboard.  She was believed to have returned to her base.
U-504	A U-boat commanded by Kapitänleutnant Wilhelm Luis belonged to Group "RAUBRITTER", "SPECHT", or "ELBE" in April and early May 1943.  This boat and U-107 supplied U-231 mid-May in the North Atlantic.  When U-231 left La Pallice 27 July 1943 she was joined by two supply U-boats and the U-boat commanded by Luis, which were on their way out from another base.  (O.N.I. Note: Luis is known to command U-504.  See also C.B.s 04051(81) & (82).  U-504 was reported sunk 30 July 1943.)
U-508	U-508 was reported sunk while under the command of

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	Kapitänleutnant Georg Staats.  (O.N.I. Note:  U-508 was reported sunk mid-November 1943.  Another source, however, places her at Lorient 4 January 1944.)
U-515	The officers of this U-boat, commanded by Kapitänleutnant Werner Henke, are: Executive officer Oberleutnant Peter Neimeyer, December 1939 Term; second watch officer, unidentified, but belonging to a 1940 Term; engineer officer, Oberleutnant (Ing.) Georg Mahnken, of the October 1937 Term.  A former executive officer was reported to have been either a reserve officer or a lower deck promotion, named Harmeln.
U-525	Reported sunk.  (O.N.I. Note:  The commander of U-525 is known to be Kapitänleutnant Jans Joachim Drewitz.)
U-526	The two halves of this boat which ran on a mine in Lorient harbor are being raised in order to recover the Diesels and several other valuable parts.  The boat itself will not be repaired.  (O.N.I. Note:  U-526 sank in Lorient 14 April 1943.)
U-530	Was reported to have left Bordeaux in November 1943.  Her commander was believed to be Kapitänleutnant Lange.  (O.N.I. Note:  It is not known which of the Langes of the German Navy List.)
U-531	Stated to have been commanded by Kapitänleutnant Herbert Neckel; the executive officer is Oberleutnant

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	Hans Georg Keitel of the October 1939 Term.  U-531 left Kiel together with U-231 and a U-boat commanded by Kapitänleutnant Werner Happe 13 April 1943.  U-531 was reported to have been in Group "RAUBRITTER", "SPECHT", or "ELBE" in April and early May 1943.  She was reported sunk on her second patrol while operating in a large group.
U-533	Reported to have been a member of Group "RAUBRITTER", "SPECHT", or "ELBE" in April and early May 1943.  (O.N.I. Note:  U-533 was sunk 17 October 1943.)
U-534	Sinking confirmed.
U-535	Sinking confirmed.
U-537	It was stated categorically that Kapitänleutnant Peter Schrewe commands U-537, not U-538.  (O.N.I. Note:  If this is true Kapitänleutnant Herbert Nollau does not command U-537.)
U-600	Kapitänleutnant Bernhard Zurmühlen was reported to have left his boat summer 1943, and his executive officer probably took over.  (O.N.I. Note:  Zurmühlen is known to have commanded U-600.  His executive officer is believed to have been Oberleutnant Rolf Erding, of the October 1938 Term.)  This U-boat, known by the cover name "Graz", may have been one of the U-boats which left La Pallice 26 December 1943 together with U-231, U-645, U-953, and U-boats.

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	commanded by Lüssow, v Lehsten, and Rahn.  (O.N.I. Note:  The U-boats commanded by the latter three have not been identified, and it is probable that one of them may now command U-600.)  She may have been damaged since, after leaving La Pallice, she returned to port but later joined a group of U-boats operating between Cape Finisterre and the Azores early in January 1944.
U-618	The U-boat commanded by Kapitänleutnant Kurt Baberg was reported having operated in a patrol group between Cape Finisterre and the Azores early January 1944.  (O.N.I. Note:  Baberg is known to command U-618.)
U-645	The U-boat commanded by Oberleutnant d. R. Ferro was probably one of the U-boats which left La Pallice 26 December 1943, together with U-231, U-600, U-953, and U-boats commanded by Lüssow, v Lehsten, and Rahn.  This boat was also reported to have returned to port for some repairs but later to have joined a U-boat group operating between Cape Finisterre and the Azores.  While in this group she claimed the sinking of a destroyer and the shooting down of an aircraft.  Some prisoners believe that the U-boat was sunk in this group as she did not answer signals sent to her.  (O.N.I. Note:  Ferro is known to command U-645, which, according to an unconfirmed report, was at La Pallice 19 January 1944.)

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U-648	The U-boat commanded by Oberleutnant Albert Stahl operated near the Azores mid-November 1943.  (O.N.I. Note:  Stahl is known to command U-648.  It is believed that U-648 was sunk 19 November 1943.)
U-758	The U-boat commanded by Kapitänleutnant Helmut Mansek entered Lorient 5 December 1943 as a guest boat of the 2nd Flotilla.  She is attached to the 3rd Flotilla at La Pallice.  The engineer officer is Oberleutnant (Ing.) Wetzenstein.  (O.N.I. Note:  Manseck is known to command U-758.  Olt. Wetzenstein belongs to the October 1939 Term.)
U-760	The U-boat commanded by Kapitänleutnant Otto Blum was reported scuttled near El Ferrol while on her 2nd patrol.  The crew was interned in Spain but later returned to France.  The boat's doctor and a radioman named Janetzki were seen at La Pallice in November 1943.  (O.N.I. Note:  Blum is known to command U-760.  This U-boat was probably damaged in an attack delivered by two airplanes from U.S.S. CARD 7 August 1943 while in company with U-664.  It is possible that she was scuttled shortly afterwards as a result of this attack.
U-952	The U-boat commanded by Oberleutnant Oscar Curio was a member of the patrol group operating early January 1944 between Cape Finisterre and the Azores.  A former executive officer on this boat was Tubinsky, who apparently was later

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	transferred to U-333.  He was succeeded as executive officer by Leutnant Freiherr von Muffling.  (O.N.I. Note:  Curio is known to command U-952.  Von Muffling belongs to the October 1939 Term.)
U-953	The U-boat commanded by Oberleutnant Karl Heinz Marbach left La Pallice 26 December 1943 together with U-231, U-600, U-645, and U-boats commanded by Lüssow, v. Lechsten, and Rahn.  She later operated in a patrol group between Cape Finisterre and the Azores early January 1944.  Her cover name at La Pallice is "Kazer".  (O.N.I. Note:  Marbach is believed to command U-953.)
U-964	On her second patrol U-231 rescued three men from a U-boat commanded by Oberleutnant Emmo Hummerjohann.  This boat had just previously been sunk by aircraft.  Hummerjohann and the rest of his crew perished.  (O.N.I. Note:  U-964, reported to have been contact keeper for Group "SCHLIEFFEN", was stated to have been sunk 17 October 1943 according to G/Serial 28.  (For details see Chapter VIII.)

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U-BOATS IDENTIFIED BY COMMANDERS

U-Borck	The U-boat commanded by Borck was reported to have operated in the patrol group between Cape Finisterre and the Azores early January 1944.  This U-boat claimed to have sunk 3 destroyers before she was forced to return to base due to an appendicitis attack of one of the crew members.  (O.N.I. Note:  Borck is not listed in the G.N.L.)
U-Burghagen	The U-boat commanded by Kapitänleutnant Burghagen was reported commissioned about two weeks before U-231, hence early November 1942.
U-Franke	The U-boat commanded by Kapitänleutnant Heinz Franke was reported to be a 500-ton boat based on La Pallice.  Her cover name is "Narvik".  She was believed to have been a member of Group "RAUBRITTER", "SPECHT", or "ELBE" April and early May 1943.  Late November or early December 1943 Franke claimed the sinking of 6 ships and a destroyer and the shooting down of two aircraft.
U-Grimme	Oberleutnant Wilhelm Grimme, who commanded U-146 from fall to April 1942, was reported in commander of an operational U-boat which was sunk with all hands.  (O.N.I. Note:  Grimme's death was announced in a newspaper 23 April 1943.)
U-Happe	The 750-ton U-boat commanded by Kapitänleutnant Happe

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	left Kiel 13 April 1943 together with U-231 and U-531.  She has been reported sunk.
U-Kinzel	The U-boat commanded by Kapitänleutnant Kinzel was reported sunk while operating in Group "LEUTHEN" early October 1943.  (O.N.I. Note:  Kinzel belongs to the 1935
U-v. Lehsten	The U-boat commanded by Oberleutnant Detlev von Lehsten was reported to have left La Pallice 26 December 1943 in company with U-231, U-600, U-645, U-953, and U-boats commanded by Lüssow and Rahn.  (O.N.I. Note:  Von Lehsten belongs to the October 1937 Term.)
U-Lüssow	The U-boat commanded by Oberleutnant Gustav Lüssow was reported to have left La Pallice 26 December 1943 together U-231, U-600, U-645, U-953, and U-boats commanded by Lehsten and Rahn.  It was stated that she operated in the patrol group between Cape Finisterre and the Azores early January 1944.  (O.N.I. Note:  Lüssow belongs to the April 1937 Term.)
U-Mäder	A U-boat commanded by Kapitänleutnant Rreich Mäder was reported to have operated in Group "LEUTHEN" early October 1943.  She was probably damaged and returned to St. Nazaire where she was seen late October 1943.  Her cover name was said to be "Wal".  Mader was reported to have a shore job

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U-Rahn	The U-boat commanded by Oberleutnant Rahn, which was based on La Pallice, was reported to have left 26 December 1943 together U-231, U-600, U-645, U-953, and U-boats commanded by Lüssow and von Lehsten.  She may have, subsequently, belonged to the group operating between Cape Finisterre and the Azores.  Her cover name was either "Hotti" or "Lotti".  (O.N.I. Note:  This was probably Wolfgang Rahn of the October 1938 Term.)
U-Schetelig	The U-boat commanded by Oberleutnant Robert Schetelig was reported to have operated in Group "LEUTHEN" early October 1943.
C-v. Trotha	A U-boat commanded by Kapitänleutnant Claus v. Trotha was stated to have been a member of Group RAUBRITTER", "SPECHT", or "ELBE" April and early May 1943.
U-Wächter	The U-boat commanded by Kapitänleutnant Karljürg Wächter was reported damaged while operating together with U-231 in Group "RAUBRITTER", "SPECHT", or "ELBE April and early May 1943.
U-Däumlein	Believed sunk.

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CHAPTER XII.  MORALE

        On the whole morale aboardU-231 was high.  That it was artificially induced became evident only when interrogators pointed out the truth as against the "Goebbels" propaganda with which most of the men, and some of the officers, were imbued.

        The Russian offensive was generally discredited as a mere temporary advance, possibly induced by the Germans to lengthen the Russian lines and to draw the enemy into a trap.  No one believed that the Russians would never reach German soil.

        It was admitted that Allied air raids were destructive, but nevertheless the morale of the home front is high.  The raids may actually increase the will to fight to the end.

        Some of the officers of U-231 were outspoken in their criticism of Grand Admiral Dönitz.  The following two incidents illustrate the reasons for their feeling of contempt.

        When Dönitz visited a French base (probably in September 1943), he bragged about U-boat production, stating that Germany would be able to build more U-boats than the enemy could sink.  This was hardly encouraging to officers who were about to leave on operational patrols.

        Twice during U-231's patrols meetings with either supply U-boats or air cover were cancelled.  Both times signals from Dönitz were received.  In effect they stated that U-boats were on their own, and since the Fatherland could depend on them, he was sure they could cary on without either additional fuel or or expected air support.  For

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this lack of cooperation Dönitz was blamed directly.  Signals od this sort were referred to as "the usual Dönitz bunk".

        In port officers often discussed the progress of the U-boat war and their dominant feeling was expressed in "What's the use?"  It was felt that the present type U-boat is obsolete and that an entirely new design is necessary to cope successfully with Allied air or escort power.  In this connection a boatswain claimed he knew that in December 1943 22 U-boats had been sunk.

        It was stated that U-boat officers at French bases listen to foreign broadcasts, including "Kameradschaftsdienst Calais" and the American broadcasts of Commander Norden.  Both were popular and believed to be quite accurate.

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ANNEX.  CREW LIST OF U-231 AND U.S. EQUIVALENTS

                                          OF GERMAN NAVAL RANKS.

	Name	Rank	USN Equivalent	Age
		Kapitan z. S.	Captain
		Fregattenkapitän	Commander
		Korvettenkapitän	Lieutenant Commander
	Wenzel, Wolfgang	Kapitänleutnant	Lieutenant	33
	von Schiefner, Friedrich	Oberleutnant z. S.	Lieutenant (j.g.)	22
	Hünefeldt, Joachim	Leutnant z. S.	Ensign	20
	Geyer, Christoph	Oberleutnant (Ing.)	Lieutenant (j.g.)	25
	Reinhard, Willi	Stabsarzt d. R.		34
	Borck, Albert	Obersteuermann	Quartermaster	31
	Brodka, Edmund	Bootsmaat	Coxswain	21
	Buchberger, Simon	Bootsmaat	Coxswain	21
	Sander, Otto	Bootsmaat	Coxswain	23
**	Didelot, Heinz	Matrose T		20
*	Doberenz	Matrosenobergefreiter	Seaman 1cl
	Dreyer, Heinz	Matrosenobergefreiter	Seaman 1cl	21
	Mansfeld, Jack	Matrosenobergefreiter	Seaman 1cl	23
	Sindt, Karl Heinz	Matrosenobergefreiter	Seaman 1cl	20
	Spribill, Erich	Matrosenobergefreiter	Seaman 1cl	21
	Taube, Kurt	Matrosenobergefreiter	Seaman 1cl	20
	Bogs, Herbert	Matrosengefreiter	Seaman 2cl	20
	Fischer, Paul	Matrosengefreiter	Seaman 2cl	24
	Klahn, Helmut	Matrosengefreiter	Seaman 2cl	18
	Lindthaler, Hans	Matrosengefreiter	Seaman 2cl	19
	Meyer, Heinrich	Matrosengefreiter	Seaman 2cl	19
	Tenninger, Helmut	Matrosengefreiter	Seaman 2cl	20
	Harders, Otto	Obermaschinist	Machinist	29
*	Hoffmann	Obermaschinist	Machinist
	Heite, Werner	Maschinenobermaat	Machinist's Mate 2cl	24
	Dubinka, Herbert	Maschinenmaat	Fireman 1cl	21
	Lohmann, Richard	Maschinenmaat	Fireman 1cl	24
	Muller, Heinz	Maschinenmaat	Fireman 1cl	23
*	Pulch	Maschinenmaat	Fireman 1cl
	Schneider, Wolfgang	Maschinenmaat	Fireman 1cl	22
	Block, Franz	Maschinenobergefreiter	Fireman 2cl	21
	Fochtmann, Gerhardt	Maschinenobergefreiter	Fireman 2cl	19
	Günther, Josef	Maschinenobergefreiter	Fireman 2cl	21
	Hubert, Heinrich	Maschinenobergefreiter	Fireman 2cl	20
	Ramsauer, Sepp	Maschinenobergefreiter	Fireman 2cl	22
	Wintwemantel, Helmut	Maschinenobergefreiter	Fireman 2cl	20
	Backhaus, Hansi	Maschinengefreiter	Fireman 3cl	20
	Kissling, Kurt	Maschinengefreiter	Fireman 3cl	19
*	Klinjer	Maschinengefreiter	Fireman 3cl
*	Klussmann	Maschinengefreiter	Fireman 3cl
*	Kreuzhuber	Maschinengefreiter	Fireman 3cl
	Scholtes, Ludwig	Maschinengefreiter	Fireman 3cl	19
	Geissler, Paul	Funkmaat	Radioman 3cl	26