NAVY DEPARTMENT

OFFICE OF THE CHIEF OF NAVAL OPERATIONS

WASHINGTON

O.N.I. 250 - G/Serial 23

REPORT ON THE

INTERROGATION OF SURVIVORS FROM U-591

SUNK ON 30 JULY 1943

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TABLE OF CONTENTS

Chapter	I.		INTRODUCTORY REMARKS
	II.		DETAILS OF U-591
	III.		CREW OF U-591
	IV.		EARLY HISTORY OF U-591
	V.		FIRST PATROL OF U-591
	VI.		SECOND PATROL OF U-591
	VII.		THIRD PATROL OF U-591
	VIII.		FOURTH PATROL OF U-591
	IX.		FIFTH PATROL OF U-591
	X.		SIXTH PATROL OF U-591
	XI		SEVENTH PATROL OF U-591
	XII.		EIGHTH AND LAST PATROL OF U-591
	XIII.		THE SINKING OF U-591
	XIV.		GENERAL REMARKS
	XV.		BASES
	XVI.		MORALE IN THE U-BOAT ARM

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Chapter I.  INTRODUCTORY REMARKS

        On 26 June 1943, five U-boats left the harbor of St. Nazaire.  From four to six weeks later, four of these U-boats were sink, all of them off the coast of Brazil.  Among them was U-591, which was attacked and sunk by VB-127-B-10, 30 July 1943 in position 08⁰ 36' S., 34⁰ 34' W.  The U-boat was discovered fully surfaced by the bomber while the latter was on air escort duty with convoy TJ-2.

        Twenty-eight survivors, including the Commander, Oberleutnant zur See Reimar Ziesmer, and three other officers, were picked up by U.S.S. Saucy and brought into Recife.  Here a preliminary interrogation was held, following which Oberleutnant Ziesmer and three ratings were flown to the United States.  Further questioning took place at an interrogation center.

        Only mild security consciousness was encountered among three prisoners who were questioned extensively, and this report is based mainly on statements made by them.

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Chapter II.  DETAILS OF U-591

TONNAGE.

        500 tons.

TYPE.

        VII C.

BUILDING YARD.

        Blom & Voss, Hamburg.

FLOTILLA.

        9th, at Brest (was "guest" at St. Nazaire).

DEVICE.

        Eagle's Head.  This device was also worn on the caps of most of the crew.

DECK GUNS.

        No guns carried fore or aft.  88-mm. gun forward removed prior to seventh patrol.

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TORPEDO TUBES.

        Four forward, one aft.  Not fitted for F.A.T. torpedoes.

TORPEDOES.

        Twelve electric torpedoes:  five in tubes; four in Bow Compartment under floor plates.  On all patrols except the last, two torpedoes were carried in upper deck containers.

S.B.T.

        This was said to have been installed after the fourth patrol.

DIESEL ENGINES.

        Two six-cylinder, four-cycle, single-acting Diesel engines, built by Germania Werke.  Rated about 1200 h.p. each.

SUPERCHARGERS.

        Two "Kasper"-type superchargers; positive displacement.  Manually operated clutches.

DIESEL ELECTRIC DRIVE--ECONOMY SPEED.

        One Diesel about 240 - 250 r.p.m.

        One electric motor about 140 r.p.m., with rudder compensation.

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ELECTRIC MOTOR SPEEDS.

Dead Slow (K.F.)	60 r.p.m.
Half Speed (H.F.)	150 r.p.m.
Full Speed (G.F.)	220 r.p.m.
Emergency Speed (A.K.)	255 r.p.m.

BATTERIES.

         Lead-acid type.  124 cells.  Maximum non-spilling diving angle:  30⁰.

        Capacity about 9,000 ampere hours.  The batteries originally built into U-591 were still in use.

STEERING GEAR.

        A.E.G. push button type in control room; portable box for use on bridge.  Hand steering gear in Stern Compartment.

AIR COMPRESSORS.

        One four-stage, crankless Junkers compressor; capacity 8 to 10 liters per minute.

        One electric compressor; capacity 6 to 8 liters per minute; load 110 volt at 30 amperes, or 4-1/2 h.p.

        Working pressures of compressors were not stated.

BILGE PUMPS.

        One main, centrifugal, pump in control room; one auxiliary, reciprocating pump also located in control room.; one auxiliary, reciprocating pump also located in control room.

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before last patrol.  The set was a Metox R-600, operative on wave lengths between 125 cm. and 250 cm.

RADIO TRANSMITTERS.

        Long wave (200 - 550 meters):  Telefunken, 150 watt.

        Short wave (50 - 100 meters):  Telefunken, 200 watt.

        Emergency transmitter (50 - 100 meters):  Telefunken, 40 watt.

RADIO RECEIVERS.

        Telefunken all wave receiver.

        Telefunken short wave receiver (10 - 200 meters).

ROD AERIAL.

        Located abaft the G.S.R. aerial.  It can be extended as high as the periscope.  It was said never to have been used.

UNDERWATER TELEGRAPH.

        Installed, but not used since the trials in the Baltic.

CALL LETTERS.

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RUBBER BOATS.

        One, possibly two, carried; one was kept under the deck grating.

MINES.

        No mines were ever carried by U-591.

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Chapter III.  CREW OF U-591

        The crew of U-591 consisted of a total of 45 men, including four officers and a doctor.  Twenty-eight men survived the sinking of their boat, among them three officers, the doctor and twenty-four ratings and enlisted men.

OFFICERS OF U-591.

        The commanding officer of U-591 was Oberleutnant z. S. Reimar Ziesmer, of the 1937 A term.  He is about 25 years old.  After spending three months at the academy as a recruit, he was sent to the training ship Horst Wessel for a quarter of a year.  He then served for about seven months on Emden on which cadet officer was Friedrich Guggenberger, who was taken prisoner when his last command, U-513, was sunk off Florianopolis, Brazil, 19 July 1943.  1 September 1939 Ziesmer was advanced to Leutnant and some time in 1940 volunteered for the U-boat arm.  No information was obtained on the further movements of Ziesmer, except that the followed the usual routine; he was sent to the submarine school, served on schoolboats and in due time became Second and First Watch Officer.  He was on his first patrol as Commander when his boat was sunk; he had succeeded Kapitänleutnant Zetzsche and had taken over U-591's command just five days before sailing on the last patrol.

        (O.N.I. Note:  From other sources it was learned that Ziesmer had been commander of U-236 when his boat was seriously damaged by an air raid on the Germania Werft, Kiel, 14 May 1943.  U-236 was at the yard for her final overhaul.)

        Ziesmer is of very slight stature; but though he appears to be physically weak, he was credited by his crew with being stronger than expected.  He definitely has been taken in by the Nazi ideology, though this is tempered.

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by his experience in the Navy, a significant part of which was the cruise on Emden, which went as far as Japan.  Ziesmer was pleasant to talk to, but his security consciousness extended to many innocent topics.

        His crew did not think very highly of him; particularly the older ratings who had participated in some of the previous patrols under Kapitänleutnant Zetzsche felt that their advice based on actual"front" experience was too lightly disregarded by the "new and green" commander.

        The First Watch Officer of U-591 was Leutnant z. S. Junkers.  (O.N.I. Note:  This may be Georg Junkers, of the December 1939 term.  From other sources it was learned that Junkers had been first watch officer on U-236 when this boat was damaged in an air raid on the Germania Werft, Kiel, 14 May 1943.  He came to U-591 together with Ziesmer.)  Junkers was the only officer who did not survive, but drowned after escaping from the U-boat. 

        The Second Watch Officer was Leutnant z. S. Ernst Lutz, of the December 1939 term.  He was appointed to the berth of Second Watch Officer on the seventh patrol and stayed on for the last patrol.

        Leutnant (Ing.) Kurt Pipal was the Engineer Officer of U-591.  He succeeded Oberleutnant (Ing.) Schubert who had been with the boat since her commissioning.  According to crew members, Pipal could not hold a candle to Schubert and the latter came along on part of the last patrol to familiarize the new Engineer Officer with his boat.  Pipal is a member of the October 1939 term.  He is about 23 years old and is married.

        A Navy doctor, Marinestabsarzt Dr. Günther Feigs, was on board U-591 when she was sunk.  He stated that he had been ordered to make the patrol with U-591 in order to gain experience for his future work in Navy hospitals.

CREW OF U-591

        Most of the surviving crew showed a rather listless attitude;

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this was no doubt partly due to the feeling that the famed German U-boat arm was decreasing rapidly in effectiveness; partly due to the fact that their new commander had not lived up to the example set by their old skipper, Kapitänleutnant Zetzsche.  The most experienced man was Oberbootsmannsmaat Köhnke who had made 15 patrols in all; some of them in a boat commanded by Korvettenkapitän Prien.  A good many of the other members had been on U-591 for several patrols, but on the whole the men were of the same standing and experience as other captured U-boat crews.

PREVIOUS OFFICERS OF U-591

        The following officers made the first four patrols with U-591:

Kapitänleutnant Jurgen Zetzsche	-	Commander
Leutnant z. S. Wolfgang Ley	-	First Watch Officer
Leutnant z. S. Joachim Sauerbier	-	Second Watch Officer
Oberleutnant (Ing.) Karl-Heinz Schubert	-	Engineer Officer.

        Kapitänleutnant Zetzsche, of the 1934 term, was considered an able U-boat commander.  He had previously served on R-boats.  After having stood by U-591's final construction period, he took her through all her trials and exercises. Zetzsche was commander of U-591 on all patrols except the last.  He was forced to give up the command by wounds received from aircraft machine gun fire shortly after putting out on the boat's seventh patrol.  Zetzsche was well liked by all of his men, and it was claimed that, on the seven patrols which he completed, he had sunk a total of about 39,000 tons of shipping.  As he was still in a hospital when U-591 left on her last patrol, it is not known  to what other command he may be transferred upon recovery.

        His first watch officer was leutnant z. S. Wolfgang Ley, of the 1938 B term.  He left after the fourth patrol, presumable to take a U-boat commander's course.  (O.N.I. Note:  On 16 October 1942, Ley was reported at Memel; in June 1943 he had just left Gotenhafen.)

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        Little is known about the Second Watch Officer, Leutnant Sauerbier.  He may be Joachim Sauerbier of the October 1939 term.

        The Engineer Officer was said to have been Oberleutnant (Ing.) Karl-Heinz Schubert who stayed with the boat until the early days of the eighth and last patrol.  Karl-Heinz Schubert belongs to the 1937 B term.  He was considered extremely efficient and was well liked by al on board. 

        The officer complement on the fifth patrol of U-591 was made up as follows:

Kapitänleutnant Zetzsche	-	Commander
Leutnant z. S. Sauerbier	-	First Watch Officer
Leutnant z. S. Helmut Krüger	-	Second Watch Officer
Oberleutnant (Ing.) Schubert	-	Engineer Officer.

        The Second watch officer, who joined U-591 for the fifth patrol, is believed to have been Helmut Krüger, of the 1938 B term.  He stayed only for two patrols, leaving after completion of the sixth patrol.

        On the seventh patrol, the following officers were on board:

Kapitänleutnant Zetzsche	-	Commander
Leutnant z. S. Sauerbier		First Watch Officer
Leutnant z. S. Ernst Lutz	-	Second Watch Officer
Oberleutnant (Ing.) Schubert	-	Engineer Officer.

RE:ATIONSHIP BETWEEN OFFICERS AND MEN.

        Relations between officers and men aboard U-591 on all except the last patrol were described as friendly and generally satisfactory.  However, when Zetzsche was relieved by Ziesmer, when Sauerbier was succeeded by Junkers and the Engineer Officer, Schubert, by Pipal, it seemed evident to the crew that their officer complement indicated a decline in the U-boat arm.  The more experienced petty officers in particular were dissatisfied, feeling that the

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young officers not only were ill equipped to handle a front boat under the present dangerous conditions, but also were unwilling to accept advice tendered with good intentions.  Ziesmer blamed part of his crew for the sinking of U-591, and his attitude towards it did little to endear his men.

PREVIOUS CREW MEMBERS.

        Obersteuermann Schleichert was a member of U-591's crew from the commissioning until the end of the third patrol, when he was succeeded by Bündgens, now a prisoner.

        Funkmaat Goltz served for three or four patrols but left U-591 prior to the last patrol.

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Chapter IV.  EARLY HISTORY OF U-591

LAUNCHING AND COMMISSIONING.

        U-591 was launched at the Blohm & Voss yard, Hamburg, either13 August or 20 August 1941.  Shortly thereafter engine room personnel and the Engineer Officer arrived to stand by the final construction period.  As usual, the seamen came later; all officers and the entire crew had assembled by the time U-591 was commissioned 9 October 1941.  A day later U-591 left Hamburg and proceeded to Kiel for her acceptance tests.

TRIALS AND EXERCISES.

        After being attached to the Fifth Flotilla, at Kiel, U-591 undertook the usual tests under the U-boat Acceptance Command (U.A.K.).  About three weeks later, early November 1941, she sailed for Danzig, stopping over at Rönne, Bornholm, where she passed her silent running test.  Ten days were spent at Danzig with additional trials and thereafter about two weeks were spent with the Active Service Training Group (Agru-Front) at Hela.  Following this, torpedo firing practice was held off Gotenhafen for about one week.  Tactical exercises lasted about two weeks and U-591 proceeded to them out of Danzig.

FINAL OVERHAUL.

        Having successfully completed all her exercises, U-591 returned for final overhaul to her building yard at Hamburg, laying over in Kiel for a day or so.  The final adjustment took about fifteen days.

PREPARATIONS FOR FIRST PATROL.

        U-591 then returned to Kiel about 10 January 1942; there she loaded

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12 electric and two air torpedoes and provisions.  After about four days, she was ready to leave on her first patrol.

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Chapter V.  FIRST PATROL OF U-591

KIEL TO KRISTIANSAND.

        Accompanied by another 500 ton U-boat and escorted by a patrol vessel, U-591 set out on her first patrol on the morning of 15 January 1942.  Kristiansand was reached about a day and a half later.  Part of the crew was accommodated on land, the other part slept on the boat.

PASSAGE INTO OPERATIONAL AREA.

        U-591 left Kristiansand in the early morning hours of 17 January 1942.  She passed through the Rosengarten into her operational area, which was believed to have been the Iceland area of the North Atlantic.  It was stated that on the passage an airplane was sighted in the latter part of January, but that the U-boat dived in time, and no attack developed.

ATTACK ON CONVOY.

        About mid-February 1942, U-591 pursued an eastbound convoy out of which she sank at least one steamer, a tanker, estimated at 8,000 tons.  The attack was made at night, from the surface.

        That same night, U-591 claims to have made attacks on two other steamers, but, though hits were believed to have been made, the results could not be observed because of the activities of the escort vessels.

        Apparently U-591 made further attempts to close the convoy the next night, but again the protecting destroyers did not permit a close approach.

RETURN TO BERGEN.

        Thirty-seven days after leaving Kiel, U-591 returned to Bergen 20 February 1942; she again passed through the Rosengarten.  All but two torpedoes had been used on the patrol.

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ATTACHMENT TO SIXTH FLOTILLA.

        Upon return to Bergen, U-591 was attached to the Sixth Flotilla, then an adjunct to the Sixth Flotilla at Danzig.

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Chapter VI.  SECOND PATROL OF U-591

DEPARTURE.

        The second patrol of U-591 was the first of three to take her into the Arctic Sea.  She put out to sea 1 April 1942, her task:  to intercept Murmansk convoys.

RAMMING BY U-657.

        About one week later U-591 was rammed by U-657, which was commanded by Kapitänleutnant Gollnitz.  The exact date could not be ascertained, but the one prisoner who was present when the boats collided claimed that it happened at night when both were on the surface.  The ramming resulted in some harm to U-591's bow.  The plating was ripped off and the torpedo tube bow caps were damaged.  Both boats were able to make Trondheim under their own power.

REPAIRS AT TRONDHEIM.

        Upon her arrival at Trondheim 11 April 1942, repairs on U-591 were made in a floating dock; she may have stayed there for about one week.  (O.N.I. Note:  U-657 has been reported being repaired at Trondheim 20 - 26 April 1942.)

PREPARATIONS FOR THIRD PATROL.

        Several stationary as well as diving trials were held after U-591 emerged from the floating dock.  She then embarked the usual 14 torpedoes, including two air torpedoes in the upper deck containers, and was again ready to set out on patrol.

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Chapter VII.  THIRD PATROL OF U-591

DEPARTURE.

        U-591 may have left Trondheim either 3 or 4 May 1942, again bound for an operational area in the Arctic, where convoys to and from Russia could be interrupted.

SIGHTING AND PURSUIT OF CONVOY.

        About Whitsuntide, 24 May 1942, U-591 sighted a Russia-bound convoy which was strongly protected.  Time after time, the U-boat was forced down by the escort vessels.  Once, she was detected by a destroyer, and about fifty depth charges were counted; four of them were fairly close.  The attack kept U-591 under water for six hours.

        About a day later, while still in pursuit of the convoy, U-591 shot several torpedoes at an  approaching destroyer which in turn forced the U-boat to submerge and then dropped four or five depth charges.  None of these were said to have had any ill effect on the boat.  (O.N.I. Note:  The convoy pursued was probably PQ 16 which was attacked 25 May 1942 in approximate position 71⁰ N., 02⁰ E.)

        U-591 is believed to have returned to Bergen about 1 June 1942 after a patrol which had lasted approximately 28 days.  About 10 of her original complement of 14 torpedoes were brought back.

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Chapter VIII.  FOURTH PATROL OF U-591

DEPARTURE.

        The exact date of the beginning of the fourth patrol could not be ascertained;  U-591 left Bergen about 20 - 25 June 1942, again bound for the Arctic.  Soon after putting out, a British submarine was sighted; evidently it was patrolling the U-boat lanes out of Bergen.  U-591 dived without making an effort to attack the enemy submarine.

PATROL LINE EAST OF BEAR ISLAND.

        After U-591 had arrived in the area just south of Bear Island an eastbound convoy was reported by one of the U-boats patrolling the convoy route.  About 10 to 15 boats formed a patrol line in an effort to intercept it.  A bit later, the convoy was reported lost by the contact keeper, and instructions were given to move further east.  Again a line was formed and again the convoy was apparently missed.  Most U-boats then proceeded further east, but almost before they had time to form another line, reconnaissance airplanes established that the convoy which had been chased by the U-boats was imaginary and nonexistent.

RETURN TO BERGEN.

        U-591 returned to Bergen after about 19 days on patrol.  She had all her 14 torpedoes still on board; she had been tempted, however, to use several of them on a British submarine which guarded the approach to Bergen.  However, for reasons unexplained, her tubes were not clear and so the opportunity had to be passed up.  It was believed that this was the same submarine which had been encountered on the way out.

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VISIT TO NARVIK.

        After about 10 days in Bergen, U-591 was ordered to proceed to Narvik, headquarters of the Admiral Commanding U-boats, North.  She arrived there about four days later, toward the end of August 1942.  In Narvik one other 500-ton U-boat was seen.  U-591's crew lived on Stella Polaris while working on their boat, which at that time received a coat of light grey paint in addition to the flotilla device of the Eleventh Flotilla to which she had been attached upon her return from the fourth patrol.  The First Watch Officer of U-591 was said to have designed the Flotilla device, which showed a polar bear against a background of icebergs holding his paws protectively over a U-boat.

RUNNING AGROUND.

        Ordered back to Bergen after two to three weeks in Narvik, U-591 ran on a rock just outside of Narvik while proceeding at half speed.  Main ballast tank #3 was damaged badly, and U-591 found herself unable to get off under her own power.  Consequently she advised the base at Narvik and four tugs arrived about a day later.  In the meantime about 10 tons of oil were dumped as was most of the ammunition for the 88-mm. gun.  After about 40 hours on a rock, U-591 was pulled free and slowly proceeded to Narvik.  There emergency repairs were made and after about two days she sailed for Bergen.

REPAIRS IN BERGEN.

        Immediately upon arrival in Bergen, U-591 went into the floating dock where she stayed from about mid-September to mid-November 1942.  The accident was investigated and both U-591's commander as well as the quartermaster were confined to quarters for four days.

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Chapter IX.  FIFTH PATROL OF U-591

DEPARTURE FROM BERGEN.

        U-591 left Bergen on 1 December 1942, her task: to intercept North Atlantic convoys.  Her course out of Bergen was about 300⁰ T; when at about 62⁰ N., 02⁰ W, course was changed to 200⁰ T, which led her directly through the passage between the Faeroes and the Shetland Islands.  When in approximate position 61⁰ N., 05⁰ W., U-591 was attacked by an airplane, but managed to dive to about 130 feet, at which depth the one bomb dropped by the plane did no harm.

PURSUIT OF EASTBOUND CONVOY.

        Course was changed to about 255⁰ T when in position 60⁰ N., 06⁰ W., and U-591 proceeded west under instructions to intercept an eastbound convoy.  She joined a group of about three U-boats which included U-553 commanded by Korvettenkapitän Thurmann.  The latter was reported to have sunk a tanker in an earlier attack on this convoy.  (O.N.I. Note:  This may have been Empire Spenser, British tanker of 8,390 tons, which was sunk with one torpedo about 0130, 8 December 1942, 600 miles west of Ireland.)