Op-16-Z
	Copy No. 18 of 52.
	NAVY DEPARTMENT
	OFFICE OF THE CHIEF OF NAVAL OPERATIONS
	WASHINGTON
	FINAL REPORT – G/SERIAL 40
	REPORT ON THE
	INTERROGATION OF SURVIVORS FROM U-371
	SUNK 4 MAY 1944
	BAD
	BUORD
	BUSHIPS
	BUSHIPS (Code 515)
	BUSHIPS (Code 815)
	COMINCH (F-21)
	COMINCH (F-4253)
	COMINCH (F-43)
	COMINCH (FX-40)
	COMINCH (FX-43)
	COMNAVEU
	DNI (Ottawa)
	G-2 (Col. Sweet)
	Op-16-1 via Op-16-1-F
	Op-16-FA-4
	Op-16-P
	Op-16-W
	Op-20-G
	Op-23-G
	SONRD
	Lt. Cdr. V. R. Taylor
	C.O., Naval Unit, Tracy, Calif.
	Lt. J. I. Eiband (COMNAVANW, CSDIC, AFHQ)
	Lt. S. R. Hatton (COMNAVNAW, CSDIC, AFHQ)
	Lt. J. T. Rugh, Jr. (JICA/ME)
	Lt. (j.g.) R. J. Mullen (4th Fleet)
	AOMASDEVLANT
	CINCLANT
	Com8thFleet
	COMNAVNAW
	Op-16-1-V
	21 August 1944

 

	TABLE OF CONTENTS
	Page CHAPTER I.   INTRODUCTION 1         II.   DETAILS OF U-371 3         III.   TORPEDO INFORMATION 9         IV.   CREW OF U-371 27         V.   HISTORY OF U-371  31         VI.   LAST PATROL OF U-371 35         VII.   SINKING OF U-371 37         VIII   DETAILS OF U-410 41         IX   EARLY HISTORY AND FIRST PATROL OF U-410 46         X   SECOND PATROL OF U-410 49         XI.   THIRD PATROL OF U-410 51         XII.   FOURTH PATROL OF U-410 53         XIII.   FIFTH PATROL OF U-410 55         XIV   SIXTH PATROL OF U-410 57         XV   SEVENTH AND LAST PATROL OF U-410 59         XVI.   OTHER U-BOATS 64         XVII.   BASES 68         XVIII.   MISCELLANEOUS 69       ANNEX   CREW LIST OF U-371 AND U.S. EQUIVALENTS     OF GERMAN NAVAL RANKS

 

	CHAPTER I.  INTRODUCTION
	U-371, a 500-ton U-boat commanded by Oberleutnant z. S. Horst Fenski, was sunk by U.S.S. JOSEPH E. CAMBELL, PRIDE and SUSTAIN:  F.F. SENGALAIS and ALCYON, and H.M.S. BLANKNEY on 4 May 1944.  The sinking occurred off Bougie, 3½ miles southwest of Ras Afia Light, after a 27 hour hunt.
	Forty-nine of the total complement of 53 were rescued, all officers, with the exception of the Engineering Officer, surviving.  A Lieutenant (j.g.) was carried as a supernumerary.
	Oberleutnant Fenski, 25 years old, had been one of the most successful U-boat captains in the Mediterranean during the recent past.  He was awarded the Knight’s Cross of the Iron Cross early this year and was credited with about 70,000 tons of shipping.  It is not thought, however, that he did in fact account for more than half this figure.  His most spectacular achievement was the sinking of H.M.S. PENELOPE off Nettuno on 18 February 1944.
	Fenski had previously commanded U-410 for five patrols, but he and practically his entire crew transferred to a veteran Mediterranean boat, U-371, when U-410 was seriously damaged in an air raid on Toulon early in March 1944.  U-371 was sunk on her first patrol under Fenski.  U-371’s previous commanding officer was Kapitänleutnant Waldemar Mehl.
	Inasmuch as U-410 was so seriously damaged at Toulon the survivors claimed she could not again become operational, and since the great majority of the survivors had served on her, the information contained in this report is preponderantly related to the
	- 1 -

 

	activity of U-410.
	Prisoners as a whole were less security conscious than those from other Mediterranean crews recently encountered, and documents were of considerable assistance in interrogation.
	Prisoners were sent to the United States for detailed interrogation following preliminary interrogation in North Africa.
	- 2 -

 

	CHAPTER II.  DETAILS OF U-371
	NUMBER
	U-371.
	TONNAGE
	500 tons.
	TYPE
	VII-C.
	BUILDING YARD
	Kriegsmarine Werft, Kiel.
	INSIGNIA
	(Formerly that of U-410)  A sword over a ring on a shield inscribed “Erst Siegen dann Heiraten” – (First Conquer then Wed) and coat of arms of patron town.  (Mehls’s insignia, a yellow dragon fly with green wings riding a brown torpedo, was wiped off.)
	F.P.N.
	M-40472.
	CALL LETTERS
	UPK.
	PATRON TOWN
	Munchen – Gladbach in the Ruhrgebiet.
	- 3 -

 

	FLOTILLA
	29th at Toulon.
	COLOR
	Standard Gray.
	ARMAMENT
	Two twin 20-mm. On Platform I.
	One 37-mm. On Platform II.
	Two MG 15’s on bridge.
	AMMUNITION CONTAINERS
	One on bridge immediately behind periscope mount.
	Two on Platform I.
	Two on Platform II.
	TORPEDO TUBES
	Four bow tubes and one stern tube.
	TORPEDOES
	Twelve carried on last patrol.  Three were T-5’s, one carried in the stern tube, one in bow tube No. II, and the third on the floor plates in the after torpedo compartment.
	SCUTTLING CHARGES
	Carried – not set at sinking.
	GREATEST DEPTH ATTAINED
	240 meters.
	- 4 -

 

	CRASH DIVING TIME
	Thirty-five to forty seconds:  this was with six or seven men on the bridge (seven if commanding officer was topside), two of whom were to man the 20-mm. Gun.
	S.B.T. (Submarine Bubble Target)
	Fitted.
	DEPTH CHARGE PLOTTER
	Not fitted.
	DIESELS
	G.W.
	SCHNORCHEL
	(Extensible Diesel exhaust and air intake.)
	Not fitted.
	FUEL OIL
	Never in excess of 120 cubic meters.
	MOTORS/GENERATORS AND SWITCHBOARDS
	A.E.G.
	BATTERIES
	A.F.A. Hagen, 62 cells per battery.
	Total Ampere hours 8200.
	COMPRESSORS
	One Junkers and one electric.
	- 5 -

 

	RADAR
	Not fitted – scheduled for installation at conclusion of patrol on which she was sunk.
	G.S.R. (German Search Receiver)
	Wanz G-2.
	Naxos – frequencies 8-12 cm.
	Borkum – frequencies 0.30 – 3.00 m.
	G.S.R. AERIALS
	“finger” and fixed basket dipole types carried.
	D/F/ GEAR
	Fitted standard long-wave D/F.
	TRANSMITTERS
	(a)  200-watt short-wave.
	(b)  150-watt long-wave.
	(c)  40-watt emergency.
	RECEIVERS
	(a)  “Main”.
	(b)  All wave.
	(c)  Elag 10/12 broadcast.
	U.K. (Ultra Short Wave)
	Not fitted.
	U.T. (Underwater telegraph)
	Fitted.
	- 6 -

 

	G.H.G. (Multi-Unit Hydrophones)
	Elag type fitted.
	ECHO SOUNDER
	Echolot fitted.
	INFRA-RED EQUIPMENT
	None carried.
	ROTARY CONVERTERS
	(a)  6 KVA.
	(b)  1.5 KVA.
	(c)  0.3 KVA.
	H/P AIR
	Standard equipment.
	OXYGEN SUPPLY
	Twelve flasks containing 120-150 liters.
	R.D.S. (Radar Decoy Spar Buoys – “Thetis”)
	Carried.
	R.D.B. (Radar Decoy Balloons – “Aphrodite”)
	Carried.
	WATER DISTILLER
	Siemens.  Produced eight liters per hr., although designed to produce ten.
	- 7 -

 

	RUBBER BOATS
	Two eight-man, one six-man, fifty-three one-man.
	- 8 -

 

	CHAPTER III.  TORPEDO INFORMATION
	A considerable amount of new information was obtained, the greater part of it from two well informed prisoners.  For purposes of convenience in this chapter the senior and better informed prisoner will be designated as source A, the junior prisoner as Source B.
	I.  COMPLEMENT
	Torpedoes and Pistols on U-371 (500-tonner, type VII-C:  four bow tubes, one stern tube):
	Location  No.  Type Pistol         Tube No. 1 1 T-3 FAT II Pi-2         Tube No. 2 1 T-5 (round nose) Pi-4C         Tube No. 3 1 T-3 FAT II Pi-2         Tube No. 4 1 T-3 FAT II Pi-2         Tube No. 5 1 T-5 (round nose) Pi-4C         On bow plates 2 T-3 FAT II (port) Pi-2     T-3 (starboard) Pi-2         Under bow plates 4 T-3 Pi-2         Under stern plates  1 T-5 (flat nose)  Pi-4C         No upper deck containers               Total  12
	At time of sinking, U-371 had the following torpedoes on board:
	T-3 in bow tube No. 1.
	- 9 -

 

	T-3 FAT II in bow tube No. 2.
	T-3 in bow tube No. 3.
	T-3 in bow tube No. 4
	T-3 under bow plates, port.
	T-3 under bow plates, Starboard.
	II.  T-5 (Flat NOSE TYPE, which is replacing round-nose type):
	A. Sensitivity:
	Listens thirty degrees on each side (as with rounded nose type).  Difference between the two types of noses described as follows:  Both types react in the same way to the horizontal field of sensitivity.  When torpedo changes course (when heeling over) the vertical field of sensitivity (in rounded-nose type) is reduced to the extent that the acoustic gear is unable to pick up vibrations in the vertical field during the torpedo’s turn, with the result that the target may be able to escape.  In the flat-nose type, however, the vertical field of sensitivity, while torpedo is turning, is maintained by four metal strips on the nose.
	B.  Apparatus Compartment (“Amsel”):
	Formerly made of cast aluminum; present composition not known.  No gas in compartment.
	C.  Battery:
	One; 30-31 cells; 70-80 volts; five or six cells have been added to those in the ordinary battery used in
	- 10 -

 

	T-2; resistor used when battery being charged; charging amp, 24.
	D.  Depth-setting gear:
	Same as in T-4.  Source A heard of a new depth-setting gear which would dispense with a spring.
	E.  Efficiency:
	Source A had heard that T-5 would eventually hit target even though target stopped and noise-makers were turned off.
	F.  Gears:
	Prisoners knew of no ball bearings for shaft gears; propeller shaft kept half-hammered in E.T.42 oil; gears of bronze.
	G.  Listening Arc:
	It was also emphatically stated that both types of T-5 (rounded-nose and flat-nose) heard 600 (300 port and 300 starboard).
	H.  Listening Range:
	Under optimum conditions, T-5 (both types) can “hear” three kilometers from target.
	I.  Pistols:
	Pi-4B:  Had been used with T-4 and T-5.  Arming distance: 300 meters.  Known as “Pendelpistole” (pendulum pistol) which reacted to a force of four kilograms.
	Pi-4C:  Now used with both types of T-5.  Arming distance: 150 meters.  Not known as a “Pendelpistole”.
	- 11 -

 

	Reacts to a force of sixteen kilograms.  Will not detonate under a glancing blow; not primarily an impact pistol; emphasis placed on its detonating under target.
	According to Source A, the pistol used is known as Pi-4C.  According to source B, the pistol is known as Pi-5C; he may be mistaken, however, in believing that the pistol number must match the torpedo number.  Both prisoners insist that the C-type is not a “Pendelpistol” (pendulum pistol), and that the emphasis given to the C-type is placed on its magnetically detonating under the target.
	J.  Pistol Arming Distance:
	Pi-4C was said to arc after a run of 150 meters.  (Arming distance of Pi-4B: 300 meters.)
	K.  Pressure Endurance:
	Guaranteed to withstand pressure up to 100 meters.
	L.  Propellers:
	Two 2-bladed propellers as on ordinary electric torpedoes.  Must be kept free of rust and blemishes and be kept well polished; dents must be hammered out.
	M.  “Quadruple Stork”:
	Not known whether four blocks are cored.  Have replaced “transformers” also in round-nosed type.
	All four strips are flush with the flat surface of nose.  No holes in vicinity of strips.  No fluid used in
	- 12 -

 

	acoustic head.  No arrangement for inflow of sea water.
	N.  Range, Speed, and Running Time:
	Source B had heard of trials held at Gotenhafen, from February 1942 to April 1943, under the TVA (Torpedo Experimental Works), at which T-5s ran 240 hectometers; he knows neither the range at 23 knots nor the end speed.  He heard recently that the running time of T-5 was between 22 and 22.5 minutes.  Source A gives range between eight and nine kilometers; speed of 24.5 knots; end speed not known.  According to hearsay, T-5 travels at the rate of 700 meters per minute.
	O.  Rudders:
	Three positions: hard over port, hard over starboard, and midships.  Rudder throw: between ten and thirteen degrees on both sides.
	P.  Running Time of T-5:
	Minimum run of T-5 said to be 17 minutes.
	Q.  WS Setting:
	Diameter of circle on WS setting: 180 meters.
	R. “Spatz” test:
	1. The following data were given by source B (who is not so sure of himself as Source A):
	a. Sound box held between 70 and 80 cm. from nose.
	b. Tested 15 degrees on each side.
	c.  Audible, oscillating sounds emitted by box.
	- 13 -

 

	d.  When box was moved from zero degrees around to 15 degrees or to any position between zero and 15 degrees, on WS or NS setting (prisoner is not sure which setting was used), there was a delay of a few seconds before the rudder was thrown hard over.
	e.  When, on NS setting, the box was turned off at any position between one degree and 15 degrees, the rudders went immediately to midships position.
	f.  Rudder went hard over when prisoner whistled as he stood in front of nose.
	2.  The following data were given by Source A:
	a.  Tested 30 degrees on each side.
	b.  Box held between 15 and 20 cm. from nose.
	c.  Audible sounds emitted from box.  Prisoner has heard of supersonic tests.
	d.  When, on WS setting, the box was moved from zero to 30 degrees or to any position between, the rudders went hard over immediately with no delay.  When the box was moved from thirty degreed to, for example, one degree, the rudders remained hard over.  When the box was returned to zero degree, the rudders remained locked
	- 14 -

 

	hard over.  When the box was removed or turned off at any position between one and thirty degrees, the rudders remained locked hard over.  After the box had been returned to zero degree (with the rudders still locked hard over) and then moved to the opposite side of zero degree (to, for example any position between one and thirty degrees), the rudders unlocked immediately on, for example, port side and swung through midships position to hard over on starboard side.  When the box was moved from, for example, any position between the one and thirty degrees on port side to any position between one and thirty degrees on starboard side (with no pause at zero degree), the rudders swung immediately through midships position to the opposite side.  (When the torpedo, fired on the WS setting, “hears” first, for example, on port side and then losses contact while turning, the rudders remain locked until the torpedo “hears” on starboard side, at which time the rudders unlock and swing through midships position without delay.)
	- 15 -

 

	e.  When, on NS setting, the box was moved from zero to 30 degrees, the rudders went hard over without delay.  When the box was moved from 30 degrees to one degree, the rudders remained hard over.  When the box was removed or turned off at any position between 30 degrees and one degree, or when the box was returned to zero degree, the rudders returned to mid-position, but under two different circumstances:
	i.  A delay of five to six seconds before rudders went to mid-position, when “Ente C” was used.
	ii.  A delay of two seconds before rudders went to mid-position when “Ente D” was used.
	Either “Ente C” or “Ente D” is used in a T-5; one is smaller than the other; “Ente C” is used more frequently than “D”.
	S.  Shock Absorbers:
	Prisoners knew of no special shock absorbers.
	T.  Speed:
	24.5 knots.
	U.  Winding on Tailpiece:
	Prisoners called this winding a “Sendespule”
	- 16 -

 

	(transmitting coil) which creates a magnetic field between itself and the pistol.  The winding has a protective rubber covering.
	V.  Ungreased Strip:
	Entire warhead must be kept free of grease.  A strip, extending from end of warhead to tailpiece and about 300 wide (from center line of torpedo - looking down -) to port and 300 to starboard, must also be kept free of grease.  Source A had been told that the ungreased strip prevented contamination of pistol; his opinion is that a greased strip will not preserve the magnetic field.
	W.  Miscellaneous:
	Flat-nose type T-5 known as “Geräuschaal” (acoustic torpedo).  Prisoner’s definition of “acoustic” was limited to a noise created by target’s propellers.  The purpose of the four metal strips are not a part of any other kind of noise receiving or sounding gear.
	III.  TRIAL DATA (round and flat nose types):
	1.  Source B was on a trial ship, the 1200-ton “HOLZAPFEL” (a sea-air rescue vessel), Summer 1942, in Danzig Bay, which fired rounded and flat nose T-5s (from its quadruple torpedo tubes, starboard) against the 5000-ton target ship “FREIBURG” which was traveling on a parallel
	- 17 -

 

	course at a range of 2000-3000 meters.  Speed of “HOLZAPFEL”: 12 to 13 knots; speed of “FREIBURG”: 9 to ten knots.  No noise-maker trailed by “FREIBURG”.  Each T-5, depth setting of 12 meters, passed under “FREIBURG” about amidships, continued to run forward for 500 to 600 meters, turned 180 degrees, again passed under target, continued run for 500 to 600 meters, turned 180 degrees, and pursued course described until end of run.  At one time the “FREIBURG” stopped dead; the T-5 then headed for the “HOLZAPFEL”.
	Propellers:
	T-5 passed under target about half way between midships and propellers.  Some T-5s were fired to pass and turn around bow; some were fired to pass and turn around stern; a few were fired to pass under midships.  But all, after the 180-degree turn, passed under
	- 18 -

 

	“FREIBURG” at midships.
	2.  The following data are from Source A:
	Firing boat was a U-boat; target ship, an 800-ton Torpedo Boat, speed of which was between 15 and 18 knots.  All T-5s on WS setting; some flat nose, some rounded nose; depth setting:  12 meters.
	X:         propellers
	A-B:      distance between, about 20 meters.
	C-D:      distance between, under 100 meters (probably 80 meters).
	E-F:      distance between, 10 to 15 meters.  Purpose was to have T-5 turn slightly aft of midships.
	X:         propellers
	Torpedo passed under propellers after turn around stern; at B, torpedo passed under propeller.  The torpedo then crept up to pass under stern of target.
	- 19 -

 

	X:         propellers
	A-B:      distance between, about 20 meters.
	Torpedo eventually pursued a snake-like course when dead astern of propellers.
	IV.  OTHER U-BOATS FIRING T-5s:
	A.  U-616 (C.O. Koitschka) fired a T-5 at a depth of 20 meters, against a destroyer, October-November 1943; detonation heard, result unknown.
	B.  Both prisoners heard at base that a U-boat C.O. (assumed by them to have been C.O. Mehl) had fired a 2-spread of T-5s. the second T-5 was fired immediately after the first; nothing hit, the second pursued the first one.
	C.  Prisoners heard that U-boat C.C. Mehl had fired a T-5 against a destroyer at a range of 150 meters; the T-5 was ineffective because the short range did not permit enough time for acoustic gear to become sensitive.
	V.  Interval Between Firing T-5s:
	Both prisoners are not certain but they believe that the interval between firing one T-5 and another T-5 is between four and five minutes.  Range and other factors must, of course, be considered.
	VI.  T-5 Magnetic Pistol:
	Pi-4C or Pi-5C is said to alternate between north and south poles about 50 times per second.
	VII.  Torpedo Personnel:
	HEINE BERGER, high frequency technician, formerly at TVA (Gotenhafen), now at service station, Toulon, specializing in pistol and frequency of T-5.
	VIII.  Tactics of U-boat Firing T-5:
	U-boat dives under following circumstances:
	1.  Impending attack by escorts.
	2.  When, on WS setting, C.O. is concerned lest target may stop and torpedo, circling, may be drawn to U-boat.
	3.  When fired at an angle torpedo may, after safety run, “hear” U-boat.
	IX.  “Saureaal” (Acid Torpedo):
	Liquid charge; propellant, which is of same composition as charge, looks like nitroglycerine.
	X.  Aircraft Torpedo:
	Trials being held with new aircraft torpedo off Usedom Island.
	- 21 -

 

	XI.  Lut:
	An improved FAT; non-acoustic; four gyro settings; 30 knots; same battery as that used in T-3s FAT II.
	Lut Setting-Gear:
	The setting gear, which was seen for only a few minutes by the prisoner at the Flensburg Torpedo School, early April 1944, replaces the old gyro and FAT setting gears.  At the school, he heard of the existence of several types of LUT setting-gears; he does not know whether the type he saw (drawn below) was an early model.  He described the arrangement as being of a lead-like composition.
	A:  Lever which, when pulled forward, caused gyro spindle to be set.
	B:  Gyro spindle, which is connected with the computer.
	C:  LUT spindles, which are set when the lever is pulled forward.
	- 22 -

Page 23 is missing.

	XIII.  Photo-electric Pistols:
	According to Source A, experiments are being carried out at Toulon on a “Schatten-Pistole” (photo-electric pistol) used with electric torpedoes.  Prisoner knew only of a glass plate on top of pistol.
	XIV.  Pi-2:
	Neither of the prisoners has heard of the Pi-2C. which designation was stamped on the pistol fitted to the one-man torpedo.  Both prisoners were asked to compare the external appearance of Pi-2C (form photographs) with that of Pi-2 (carried by U-371).  With the exception of the missing Pi-2C water-tripper and whiskers, both pistols were said to be externally identical.
	The following data pertain only to Pi-2 (which has been in service since the end of 1942):
	A.  Four Plugs on Body of Pistol  (looking at pistol head on; plugs numbered from right to left.):
	1.  Plug No. 1:  Test plug; 4.5 volt bulb lights up if pistol has been fitted properly to make contact.
	2.  Plug No. 2:  On-off switch for magnetic firing; no longer used.  If desired to fire torpedo with magnetic firing cut out, torpedo is withdrawn about three meters from tube, and switch, located in motor chamber, is turned to “off” position.
	- 24 -

 

	3.  Plug No. 3:)  Not used; prisoners had heard
	4.  Plug No. 4:)  that these two plugs were to be used in an improved Pi-2.
	B.  Power to Amplifier:  Taken from main propulsion battery.
	C.  Battery Voltage:  Usually 110 volts; 124 volts after charging; 115 volts two days after charging; drops to 104-106 during run.
	XV.  Spreads:
	In a spread of 2 or 3 or 4, the interval between shots is said to be 2.3 seconds; timing is done automatically by means of a time switch.
	XVI.  T-4:
	Originally known as G7eS, “S” signifying “Sonderartsführung” (special manner of behavior).
	XVII.  T-9:
	Liquid charge; propellant of same composition as charge (highly sensitive); speed of 60 knots; torpedo tear-drop shape; larger diameter and shorter in length than usual 21-inch torpedo.
	XVIII.  Tube Caps:
	Caps may be kept open up to 100 meters depth, but are usually closed at 30 meters.
	- 25 -

 

	XIX.  U-boat Firing Depth:
	25 to 30 meters is said to be the maximum depth of a U-boat firing all types of torpedoes.
	- 26 -

ILLUSTRATIONS

  GERMAN ACOUSTIC TORPEDO

  T-5      ( FLAT NOSED TYPE )

Click on the text to view the illustration

PLATE I	APPARATUS COMPARTMENT
PLATE II	WARHEAD
PLATE III	BATTERY COMPARTMENT
PLATE IV	MOTOR AND APPARATUS COMPARTMENT
PLATE V	WIRING DIAGRAM OF T-5
PLATE VI	AIR LEADS
PLATE VII	GYRO - G.A.8
PLATE XIII	FIG. 1 GYRO STEERING ENGINE
	FIG. 2 ACOUSTIC CONTROL GEAR
PLATE IX	DEPTH SETTING GEAR
PLATE X	DEPTH SETTING ENGINE
PLATE XI	TESTING GEAR

 

	CHAPTER IV.  CREW OF U-371
	Practically nothing is known of U-371’s officers up to her seventh patrol.  She was commissioned by Kapitänleutnant Heinrich Driver of the 1933 Naval Term.  He remained in command until sometime prior to the seventh patrol when he was relieved by Kapitänleutnant Waldemar Mehl, also of the 1933 Term.  Mehl was in turn relieved by Oberleutnant zur See Horst Arno Fenski of the 1937 Term prior to U-371’s last patrol.
	U-371’s officers during her career are shown, as far as they are known, below:--
	FIRST THROUGH (?) PATROL
	Kapitänleutnant Driver, Commanding Officer.
	SEVENTH PATROL
	Kapitänleutnant Mehl, Commanding Officer.
	Leutnant zur See Scholz, First Watch Officer.  (Not in GNL)
	Leutnant zur See Hassenfelder, Second Watch Officer.
	Oberleutnant (Ing.) Becker, Engineering Officer.
	EIGHTH PATROL
	Kapitänleutnant Mehl, Commanding Officer.
	Leutnant zur See Scholz, First Watch Officer.
	Leutnant zur See Steinfeld, Second Watch Officer. (Not in GNL).
	Oberleutnant (Ing.) Becker, Engineering Officer.
	- 27 -

 

	NINTH PATROL
	Kapitänleutnant Mehl, Commanding Officer.
	Leutnant zur See Steinfeld, First Watch Officer.
	Leutnant zur See, Hillmann Second Watch Officer.
	Oberleutnant (Ing.) Becker, Engineering Officer.
	TENTH THROUGH THIRTEENTH PATROLS
	Kapitänleutnant Mehl, Commanding Officer.
	Leutnant zur See Steinfeld, First Watch Officer.
	Leutnant zur See, Hillmann Second Watch Officer.
	Oberleutnant (Ing.) Becker, Engineering Officer.
	FOURTEENTH AND FIFTEENTH PATROLS
	Kapitänleutnant Mehl, Commanding Officer.
	Leutnant zur See Sausmikat, First Watch Officer.
	Leutnant zur See, Hillmann, Second Watch Officer.
	Leutnant (Ing.) Deichsling, Engineering Officer. (Not in GNL)
	SIXTEENTH AND SEVENTEENTH PATROLS
	Kapitänleutnant Mehl, Commanding Officer.
	Oberleutnant zur See Vanselow, First Watch Officer.
	Leutnant zur See, Hillmann, Second Watch Officer.
	Leutnant (Ing.) Deichsling, Engineering Officer.
	LAST PATROL
	Oberleutnant zur See Fenski, Commanding Officer.
	Leutnant zur See Mueller, First Watch Officer.
	- 28 -

 

	Oberleutnant zur See Wagner, Second Watch Officer.
	Oberleutnant (W) Bressler, (Supernumerary).
	Oberleutnant (Ing.) Ritschel, Engineering Officer.
	Fähnrich, (Ing.) Siebert, Second Engineering Officer.
	Little is known of the above men prior to U-371’s last patrol, although Mehl was apparently a popular officer.  Morale was said to have been kept high by long leaves for the crew.  Fenski was apparently popular with his crew, who regarded him highly.  Upon interrogators he made a poor first impression, being arrogant and demanding.  But he later proved more pleasant and can be rated one of the better types of U-boat commanders seen by interrogators in this war.
	Leutnant zur See Mueller was chiefly remarkable for the fact that he had spent some years in California and had attended Los Angles Junior High School.  This experience, however, did not prevent him from becoming an adamant young Nazi.
	Oberleutnant zur See Wagner was a nondescript and average officer.
	Nothing is known of the career of Oberleutnant (Ing.) Ritschel who did not survive the sinking.
	Very little was developed on the supernumerary officer Oberleutnant (W) Bressler.  He was believed to have stood some watches on board, but spent most of his time with Fenski and playing cards in Fenski’s cabin.  Under interrogation he feigned mental unbalance.  He had previously suffered two brain concussions and his
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	physical condition had kept him form active sea duty during the war.  As a result, he claimed, he took advantage of a period of leave to go on patrol in a U-boat to get a closer view of the war he had missed.  What if any, his official duties on board were, is not known.
	The crew, as might be expected from their record, were of higher than average caliber.  They were not, however, unduly security conscious under interrogation.
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	CHAPTER V.  HISTORY OF U-371
	With few exceptions, the entire crew of U-371 was returned to Germany when she was taken over by Fenski and his men.  Consequently, little information was available on the early history of U-371.  She is believed to have been commissioned at the Kriegsmarine Werft, Kiel sometime in February or March 1941, under the command of Kapitänleutnant Henrich Driver, and was one of the first U-boats in the Mediterranean.  It is believed that U-371 made about eighteen patrols during her career.
	EARLY HISTORY
	Nothing is known of U-371’s trials and working up period; with a single exception nothing is known of the first six patrols.
	On 16 December 1941 the German High Command announced that Driver had sunk a British cruiser of the LEANDER class off Alexandria.  (O.N.I. Note:  H.M.S. GALATEA was sunk 14 December 1941 off Ras El Tin Light.)
	SEVENTH PATROL
	What is believed to have been U-371’s seventh patrol began about 10 September 1942 from Pola with Mehl in command.  Her operational area was off the Levant Coast, particularly off Jaffa and Beirut.  After fifteen days at sea, during which time she sank nothing, she put into Salamis, but sailed immediately for Pola, which she reached about 25 September.
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	EIGHTH PATROL
	U-371 left Pola about 1 December 1942 to operate off North Africa in the Western Mediterranean.  It was claimed that she sank a 6000-ton freighter and a sub-chaser on this patrol, and was attacked by aircraft which dropped three bombs close aboard.  U-371 was not seriously damaged, however.  (O.N.I. Note:  On 12 December 1942 the British Ship OCEAN VANQUESTIER of 7174 tons and the Norwegian BERTO of 1493 tons were sunk in position 36.48 N. – 03.04 E.  On 7 January 1943 the British A/S vessel JURA was sunk in position 36.58 N. – 03.48 E.)  U-371 put in to La Spezia about 10 January 1943.
	NINTH PATROL
	U-371 claimed to have sunk two freighters on her ninth patrol, again operating in the Western Mediterranean close to the African Coast, after leaving La Spezia about 2 February 1943.  After an otherwise uneventful patrol she put in again to La Spezia about 28 February 1943.
	TENTH PATROL
	U-371 sailed from La Spezia for her next patrol about 30 March 1943.  Her operational area was again the Western Mediterranean.  She claimed to have sunk one freighter of about 4000 tons before putting into Toulon about 7 May 1943.
	ELEVENTH PATROL
	U-371 left Toulon about 2 July 1943 to operate off the
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	western coast of Italy.  Two freighters of about 18,000 aggregate tons were claimed sunk and U-371 was stated to have been heavily depth-charged (about 40 depth-charges) by a destroyer.  She suffered slight damage and returned to Toulon about 13 July 1943.
	TWELFTH PATROL
	On or about 24 July U-371 left on her next patrol and returned to her old area in the Western Mediterranean.  During this patrol she again stayed close to the African coast.  She claimed the sinking of one steamer of unknown tonnage before returning to Toulon about 12 August.
	THIRTEENTH PATROL
	U-371 left Toulon about 21 August for her next patrol where she operated in the Western Mediterranean and off Nettuno without success.  She returned to Toulon about 4 September 1943 and, during the ensuing docking period, the 88-mm gun was removed and Platform II with the quadruple 20-mm. was added.  In addition, two twin 20-mm. replaced the two single mount 20-mm. on Platform I.
	FOURTEENTH PATROL
	U-371 left Toulon on her next patrol about 22 September to operate off Africa in the Western Mediterranean and was again unable to sink any ships.  On this patrol U-371 was attacked several times by aircraft.  She was once caught by surprise and was unable to submerge in time, but Mehl, confident of his new armament, elected to fight it out on the surface.  After three
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	passes the plane gave up further attacks and flew away.  The patrol ended at Toulon about 10 October 1943.
	FIFTEENTH PATROL
	U-371 left Toulon about 26 October to again patrol the African coast in the Western Mediterranean.  She claimed the sinking of two destroyers and one freighter on this patrol.  She returned to Toulon about 23 November to find the city badly damaged by an Allied air raid during her absence.  (O.N.I. Note:  On 2 November 1944 FF MONT VISO in convoy KMS 30 was sunk in position 36.45 N. – 01.55 E.  On 6 November 1944 the U.S.S. BEATY was sunk in position 37.13 N. – 06.21 E.)
	SIXTEENTH PATROL
	U-371’s last patrol under Mehl began about 12 March when she left Toulon for her old area off the coast of Africa.  She claims to have sunk two or three freighters, and to have again escaped serious damage when attacked by an aircraft which dropped four bombs.  She returned to Toulon about 25 March and most of her crew were returned to Germany to take over a new boat.
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	CHAPTER VI.  LAST PATROL OF U-371
	U-371, now under the command of Fenski, left Toulon on her last patrol about 1900 on 23 April 1944.  She was escorted as far as Cape Cepet by two small harbor craft.  This was stated to be routine procedure.  On her way to her operational area, which again was to be off the coast of Africa, she remained surfaced all night and steered a course almost due South.  Upon her arrival, she patrolled between Cape Bengut and Cape Sigi, from 10 to 15 miles off shore.
	About 26 or 27 April, in the morning, while proceeding submerged, she picked up screw noises on her hydrophones, and on coming to periscope depth , sighted two troop transports, one of 12,000 tons and one of 14,000 tons, escorted by three French destroyers.  Tubes Nos. 1 and 3 armed with FAT’s set long with 150 right gyro were fired at the 14,000 ton ship, and about a minute later Tube No. 4 also armed with an FAT was fired at the smaller ship.  All three torpedoes missed as did a T-5 fired at one of the destroyers from Tube No. 2 about a minute and a half later.  After about twelve minutes, three explosions were heard as U-371 was leaving the scene at slow speed at about 40-50 meters.  It was stated that the torpedoes were set to destroy themselves after they sank to a depth of 120 meters.  (O.N.I. Note:  There is no record of any such attack.)
	On the 28th of April U-371 received a signal from Control about an Eastbound convoy which she was to intercept off Cape
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	Bougaroun.  She failed to contact this convoy, but on the next day she received another signal giving details of three convoys.  One of these, Eastbound, was stated to consist of 97 vessels, including eight tankers and fifteen escorts.
	It was apparently about this time that Fenski, while searching for the convoys at periscope depth, saw three aircraft flying nearby.  One of the planes was seen to circle them once and Fenski took the boat to about 100 meters, no attack developing.  After waiting for some time U-371 came to 30 meters.
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	CHAPTER VII.  SINKING OF U-371
	On the night of 2 May Fenski decided to surface and top up his batteries as he expected to contact the convoy some few hours later.  When U-371 came up she found herself almost in the middle of the convoy, and immediately crash-dived to about 100 meters.  Fenski surfaced once again in about an hour and headed toward the convoy, assuming his batteries would be charged by the time he was able to make contact again.  Shortly thereafter it was reported to Fenski that U-371 had been detected by surface craft, so he immediately changed course and attempted to escape on the surface, wishing to avoid contact until his batteries were fully charged.  U-371 remained on the surface until the destroyer had closed to about 3,000 meters.  She then fired a T-5 from her stern tube, and immediately dived to over 100 meters.  After about five or six minutes an explosion and sinking noises were heard, and they assumed the pursuing destroyer had been sunk.  (O.N.I. Note:  The U.S.S. MENGES was hit by a torpedo in position 37.03 N. – 05.24 E. at about 0142 on 3 May.  She was later able to make port.)
	When Fenski gave the order to return to the surface, faint screw noises and distant depth-charge explosions were heard when they reached about 60 meters.  AS the screw noises became more audible, Fenski took his boat down again to about 160-180 meters and headed toward the coast at slow speed, thinking that this was just the opposite of what would be expected of him.  Soon, however, a very accurate series of depth-charges exploded
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	around the boat, putting out all lights, damaging the hydroplanes, and rupturing the trim tanks.  Finally Fenski was forces to blow the No. 3 diving tank to level the boat off at about 200-215 meters.  The glans leaked badly at this depth and the water entry increased as the attacks continued at about 30-minute intervals, each one being more accurate than the one before.
	As the attack developed the starboard propeller shaft was thrown out of line, the armature of the starboard motor ran excessively hot, and the motor/generator supplying the current to the gyro-compass became noisy, necessitating turning off the gyros.
	The last series of depth-charges during this stage of the attack, and also the closest, came at about 0600 on 3 May, and shortly thereafter Fenski decided to bottom to make detection by Asdic more difficult and to save his batteries.  Having been submerged most of the day, and having had only a very short time to charge them the night before, the batteries were becoming dangerously low and were a cause of great concern to Fenski.
	U-371 first bottomed out at about 170 meters at a rather steep angle and had to back off and bottom again, this time considerably deeper (about 240 meters), but where a more level trim was possible.  Although water entry through the glans was quite heavy at this depth, they lay there unmolested all day long, hoping that their attackers had given up the hunt.
	Late that night, however, surface craft were again heard in the vicinity, and with air in the boat rapidly
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	getting worse, the emergency lighting system out, and about 15 tons of water throughout the boat, Fenski decided that his only hope was to surface and attempt to escape on his Diesels in the darkness.
	They tried to blow their tanks but the boat was so heavy by this time that the 40 kilos of high pressure air that remained was insufficient to do the job, and the maneuver resulted only in attracting the destroyers which began dropping depth charges again.  The situation was now becoming desperate with the control room knee-deep in oil and water.  The whole crew was ordered aft, and the electric motors run full speed ahead.  Again the boat failed to budge, so the crew was sent forward and the engines set astern full.  After repeating this procedure several times the boat finally freed itself and began rising to the surface at a 600 angle.  All tubes were loaded and made ready for firing, and when the boat finally reached the surface all guns were manned and U-371, with her batteries practically exhausted, ran for open water.
	Nothing was sighted for about fifteen minutes, when surface craft were detected coming up astern.  Almost immediately Fenski shouted, “Prepare to scuttle ship”.  They were immediately engaged by gunfire from the pursuing destroyers which scored several hits, and though fire was returned at first, the situation was considered hopeless and several of the crew began jumping overboard.  The engine room personnel and torpedomen remained below,
	- 39 -

 

	however, as Fenski still had hope of sinking the attacking ship and making good his escape.
	It was then found that, although all tubes were loaded and ready, two of them had been damaged and could not be fired.  A T-5 was then fired from the stern tube, after most of the crew had left the boat.  The shot was a very hurried one, and little, if any, aim was taken.  But, due partly to luck and partly to the qualities of the T-5, a hit was scored on one of the destroyers.  (O.N.I. Note:  The F.F. SENEGALAIS was torpedoed at about 0400 on 4 May 1944 while pursuing a surfaced submarine about one mile off Djidjelli.)
	By this time only Fenski, who was on the bridge, and two others, the Engineering Officer and a control room petty officer remained aboard.  The latter two remained below to flood tanks 1, 3 and 5 which caused U-371 to sink so rapidly that they were not able to escape.  Scuttling charges were not set, and though an attempt was made to signal Control about U-371’s fate, it is believed that no contact was made.
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	CHAPTER VIII.  DETAILS OF U-410
	TONNAGE
	500 tons.
	TYPE
	VII-C standard.
	BUILDING YARD
	Danziger Werft – Danzig.
	LAUNCHED
	Early January 1942.
	COMMISSIONED
	3 – 4 March 1942.
	YARD NUMBER
	M-43581.
	CODE NAME
	While at St. Nazaire – Stürmer.
	FLOTILLA
	While at Kiel belonged to the 5th Flotilla, at St. Nazaire to the 7th Flotilla, and while at Lorient was guest boat of the 10th Flotilla.  In the Mediterranean belonged to the 29th Flotilla.
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	COLOR
	In the Atlantic the U-boat had standard gray paint, in the Mediterranean the boat was camouflaged with light and darker gray diagonal stripes.
	INSIGNIA
	Formerly Bull of Scapa Flow of 7th Flotilla, but this was painted out prior to entering the Mediterranean.  In the Mediterranean the insignia was a sword and a ring on a shield.
	GUNS
	Two twin 20-mm. guns on Platform I.
	One quadruple 20-mm. gun on Platform II.
	Two type 81 M.G.’s on bridge.
	AMMUNITION CONTAINERS
	Four on bridge (pressure proof).
	TORPEDOES
	Carried fourteen torpedoes on first three patrols, twelve torpedoes on all later patrols.  Upper deck containers removed after third patrol.
	TORPEDO TUBES
	Four bow and one stern tube.
	SCUTTLING CHARGES
	Total of 5,000 lbs. Of scuttling charges were kept in
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	the Captains cabin and officers’ quarters.
	GREATEST DEPTH OBTAINED
	240 meters.
	CRASH DIVING TIME
	28 seconds on trials, 32/34 seconds on operational patrol.
	S.BT. (Submarine Bubble Target)
	Fitted after second patrol.
	DIESELS
	G.W.
	SUPERCHARGERS
	Büchi.
	FUEL OIL CAPACITY
	132 tons, including four tons in torpedo compensating tank.
	AVERAGE DAILY FUEL OIL CONSUMPTION
	1.5 cubic meters, in Atlantic; 2-2.5 cubic meters in Mediterranean.
	MOTOR/GENERATORS
	Siemens.
	- 43 -

 

	BATTERIES
	Hagen, lead acid type, 62 cells each, total amp. Hours 8,000.
	COMPRESSORS
	One Junkers Compressor.
	One Electric Compressor.
	GERMAN ASDIC
	Not fitted.
	GEMA RADAR
	Fitted after fourth patrol, mattress aerial with two rows of four dipoles.
	G.S.R. (German Search Receiver)
	Borkum and Wanz G-2 fitted after fourth patrol.  Naxos added after fifth patrol.  Standard fixed drum-shaped G.S.R. aerial.
	LONG-WAVE D/F/ (Direction Finder)
	Fitted.
	G.H.G. (Multi-Unit Hydrophone)
	Fitted.
	ECHO SOUNDER
	Atlas type fitted.
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	K.D.B.
	Removed after fourth patrol.
	OXYGEN
	150 liters in twelve bottles.
	R.D.S.
	Five R.D.S. carried on seventh patrol to be used if contacts were received on Naxos.  No such contacts were received.
	R.D.B. (Radar Decoy Balloons)
	Carried 30-40 R.D.B.s on fifth and sixth patrols, always used.  Four hydrogen flasks were fitted on bridge for use in this connection.
	RUBBER BOATS
	53 one-man rafts.
	2 eight-man rafts.
	2 six-man rafts – stored in place of upper deck torpedo container.
	FRESH WATER DISTILLER
	Made by Siemens.
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	CHAPTER IX  EARLY HISTORY AND FIRST PATROL OF U-410
	LAUNCHING
	U-410 was launched at Danzig early in January 1942.  From then until early March the crew stood by during the final phases of construction.
	COMMISSIONING
	On the third or fourth of March 1942 U-410 was commissioned at Danzig.
	TRIALS IN THE BALTIC
	The Baltic trials were conducted at Gotenhafen, Danzig, Rönne, etc., without incident.
	FINAL OVERHAUL AND PREPARATIONS FOR SEA
	The final overhaul was completed at Danzig during July and early in August.  U-410 proceeded to Kiel for provisioning and final wiping.
	FIRST PATROL
	U-410 now attached to the 5th Flotilla left Kiel for her first patrol under the command of Korvettenkapitän Sturm on 27 August 1942 and proceeded in company with UD-3 and U-Breithaupt to Kristiansand, where she stayed for two or three days before leaving for the passage through the Rosengarten to her operational area off Halifax.  (O.N.I. Note:  UD-3 is an ex-Danish submarine and Breithaupt is thought to have commanded a 500-ton U-boat.)
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	U-410 JOINS GRUPPE PANTHER, GRUPPE LEOPARD, and GRUPPE WOLF
	The month of September 1942 was fairly uneventful, and early in October U-410 was ordered to join the patrol Groups Panther, Leopard, and Wolf.  (O.N.I. Note:  Gruppe Panther consisted of about 19 boats among them being U-618, U-109, U-118+, U-662+, U-113+, U-615+, U-607+, U-353+, U-620+, U-174+, U-221+, U-706+, U-Makowski+, and U-Schultz,(W).  Groups Leopard and Wolf consisted of about six and ten boats, respectively.  They operated in the North Atlantic between 6 and 16 October 1942.)
	GRUPPE LETZTE
	Upon the dissolution of Groups Panther, Leopard, and Wolf about mid-October 1942, U-410, together with the other boats of these groups, which had sunk nothing, were formed into a new group ironically called LETZTE RITTER (Last Knight).  In this group were said to have been U-Breithaupt, U-Baberg (N.I.D. U-618), U-Bleichrodt (N.I.D. U-109) and a boat referred to as U-Jonas.  (O.N.I. Note:  Two prisoners of war were sure this boat was U-441.  This is known to be incorrect and there is no record of a boat under the command of such an officer at this time.)
	FIRST SINKING
	On the 46th or 47th day of the patrol, while in this group in the North Atlantic, they sank a 3000-ton freighter northwest of the Azores.  (O.N.I. Note:  On 17 October a U.S. freighter, the S.S. ANGELINA of 4772 tons was sunk while in ON 137 in position 49.39 N. – 30.20 W.)  After the ship sank U-410 cruised among
	- 47 -

 

	The life boats seeking the Captain, but were informed that he had gone down with his ship.
	U-410 then proceeded to port, arriving at St. Nazaire at the end of October or early November after about 53 days at sea.  She was then assigned to the 7th Flotilla and the next four weeks were spent at St. Nazaire in preparation for the next cruise.
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	CHAPTER X.  SECOND PATROL OF U-410
	The exact dates of the second patrol were not established but it is believed from other sources to have begun about 10 December 1942 and to have lasted until about 6 January 1943 when they again put into St. Nazaire.  During this time U-410 is thought to have been operating in the Central Atlantic.
	It was during this patrol that U-410 together with U-407 and U-409 were ordered by Control to meet and escort the incoming blockade-runner RHAKOTIS somewhere northwest of the Azores.  (O.N.I. Note:  U-407 was a 500-ton boat which has since probably been sunk.  U-409 was a 500-ton boat later sunk 12 July 1943.)
	RENDEZVOUS AND SINKING OF BLOCKADE-RUNNER “RHAKOTIS”
	After making contact with the “RHAKOTIS” U-410 proceeded 40 miles ahead with U-407 and U-409 about 20 miles on either beam of the “RHAKOTIS”.  (O.N.I. Note:  The “RHAKOTIS” was intercepted and sunk on 1 January 1942 in position 45.00 N. – 10.50 W. by British surface forces.)  On the day she was sunk, U-410 again made contact with her and then proceeded on ahead again in a northeasterly direction.  Early the next morning the three U-boats received word from Control informing them that the RHAKOTIS had been sunk and ordering them to proceed to the scene and pick up survivors.
	RESCUE OF “RHAKOTIS” SURVIVORS
	U-410 reached the area about 16 hours after the sinking
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	and sighted two lifeboats with about 80 survivors.  The survivors told them that there were two other lifeboats but U-410 could not locate them.  They learned later, that these two boats had been able to reach the coast of Spain.  U-407 and U-409, also searching the area, were unable to locate the survivors, nor were they seen by U-410.
	Having effected the rescue, U-410 returned to port, arriving in St. Nazaire about a week later.
	The next six weeks were spent in the usual preparations for the next patrol.  During this period Sturm was transferred and Fenski took over command of U-410.
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	CHAPTER XI.  THIRD PATROL OF U-410
	U-410, now under the command of Oberleutnant Fenski, left on her third patrol about 17 February 1943 from St. Nazaire to operate in an area southwest of Spain.
	Early in the patrol a 27,000-ton two-stacker was sighted, but, owing to her high speed and poor visibility, U-410 was unable to attack.
	During this patrol torpedoes were fired at three freighters and Fenski claimed the sinking of two.  However, the Deutscher Geheindienst (Intelligence) gave him credit for sinking three ships of 18,000 tons total.  (O.N.I. Note:  Three ships, the TREFUSIS, 1574 tons; EMPIRE TOWER, 5299 tons; and FIDRA, 4378 tons were sunk on 5 March in position 43.56 N. – 14.53 W. and these may be the ones referred to.  No other sinkings are known to have taken place within this area in this period.)
	U-410 also claims that during this patrol she was attacked by two destroyers but suffered no damage.  (O.N.I. Note:  This may have been the attack by H.M.C.S. SHEDIAC and H.M.C.S. ST. CROIX on 4 March 1944 in position 44.46 N. – 13.31 W.)
	On the return passage, U-410 sighted a convoy as they were approaching the Bay of Biscay, but seven or eight G.S.R. contacts forced U-410 to dive and prevented an attack.
	At the conclusion of this patrol, U-410 put into Lorient as a guest boat for the next seven weeks.  It was during this time that the Executive Officer, Leutnant zur See Koenig was transferred
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	and was succeeded by Leutnant zur See Peters.  Leutnant Breun became Second Watch Officer.
	- 52 -

 

	CHAPTER XII.  FOURTH PATROL OF U-410
	U-410 ENTERS THE MEDITERRANEAN
	U-410 left Lorient on her forth patrol on 27 April 1943 and proceeded to the Mediterranean.  Passage of the Straits was begun the night of 5/6 May, and the U-boat proceeded, surfaced 10 to 20 miles off the coast of Spanish Morocco.  Off Gibraltar itself, at dawn of 6 May, U-410 dived and proceeded submerged at a depth of 50-60 meters.
	AIRCRAFT ATTACK
	In the forenoon of 6 May, U-410 was attacked by a twin motor aircraft which was only sighted when she was about 200 meters away, having come out of the sun.  The plane raked U-410 with gunfire and dropped three bombs which fell five to ten meters ahead of the U-boat.  Considerable panic reigned on deck:  the Commanding Officer and everybody else were yelling contradictory orders, but below the order to dive was heard and promptly obeyed.  The conning tower hatch was closed, and U-410 crash-dived with three men still on the bridge.  At the last moment, Fenski, who was in the conning tower, realized what had happened and ordered the boat to resurface.  By this time the three men topside were in water up to their arm pits.  Fenski and others rushed to the bridge and manned the machine guns as the plane prepared for another run.  They were successful in forcing it to break off its run before any bombs were dropped, but it continued to circle U-410 at a distance during which time
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	mutually ineffective gun fire was exchanged.  Finally after about 45 minutes the plane dropped a parting salvo of three bombs, all of which fell about 200 meters away.  The plane then departed and U-410 submerged.  (O.N.I. Note:  There is no record of such an attack on 6 May, but this may have been the attack by a RAF Hudson of 500 Squadron delivered at 0943 GCT on 8 May 1943 in position 35.47 N. – 02.20 W.)
	When the heat of battle had died down it was discovered that there was a break in the pressure hull forward, between the torpedo tubes, about five meters long, through which a stream of water about 1 ¼ inches thick was spurting.  In addition all the bow caps on the forward torpedo tubes were damaged.
	This concluded, for all practical purposes, the fourth patrol, and U-410 arrived at La Spezia on 12 May 1943 and was attached to the 29th Flotilla.  She was immediately put into drydock and repairs lasted until sometime in early August.
	ADDITIONAL ARMAMENT ADDED
	During the ensuing docking period the conning tower was rebuilt. Platform I lengthened and twin Breda 1.5 retractable machine guns were mounted on the bridge.  The single 20-mm. was removed.
	Müller, who eventually became U-410’s Executive Officer, joined the boat at this time as Third Watch Officer pupil with the rank of Oberfähnrich.
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	CHAPTER XIII.  FIFTH PATROL OF U-410
	U-410 left La Spezia about five or six days after the fall of Mussolini and proceeded to operate off Salerno.  (O.N.I. Note:  This was probably about 1 August as Mussolini resigned on 25 July 1943.)  This part of the patrol was uneventful except for the firing of two torpedoes which missed a “2800-ton net layer”.
	U-410 was then ordered to proceed to the area off Bone.  On the way they were attacked by an aircraft which promptly disappeared into a cloud and was seen no more.  Prisoners were of the opinion that this may have been a German plane, and, inasmuch as there is no record of such an attack at this time or position by an allied plane, this may be a possible explanation.
	About the 20th or 22nd of August prisoners claim they sighted a 22,000 ton transport and fired a spread of four torpedoes at her.  Although they claimed hits, they did not say the ship had been sunk.  (O.N.I. Note:  There is no record of any such attack other than the damaging of a medium U.S. freighter, the PIERRE SOULE, on 23 August in position 38.21 N. – 12.50 E.)
	On the night of 25/26 August 1943 U-410 claims to have sunk three ships totaling 20,000 tons out of an eastbound convoy.  (O.N.I. Note:  SS JOHN BELL of 7242 and SS RICHARD HENDERSON of 7194 tons were sunk while in convoy UGS 14 on 26 August in position 37.12 N. – 0821 E. and 37.15 N. – 08.22 E. respectively.)
	U-410 concluded her fifth patrol after only three or four weeks at sea and put into Toulon early in September 1943.  The
	- 55 -

 

	next ten days were spent in preparations for her sixth patrol during which time Peters left the boat and Müller became Second Watch Officer.  Leutnant Ritschell came aboard as Engineering Pupil under Rachner who was to be transferred after the next patrol.
	- 56 -

 

	CHAPTER XIV.  SIXTH PATROL OF U-410
	U-410 left Toulon on her sixth patrol about mid September 1943 and proceeded at once to Salerno at high speed.  Soon after her arrival, U-410 sighted a 10,000-ton ship and a cruiser, but was unable to get into position to attack.  She did, however, fire a torpedo from tube No. 4 at a net layer, but the torpedo broached and U-410 maneuvered for a shot from tube No. 1.  Although the torpedo ran satisfactorily, it too failed to find its target.
	While Fenski was waiting for an opportunity to get into the harbor itself U-410 was attacked by an aircraft which was thought to be German.  Later U-410 was discovered and attacked by a destroyer without suffering any damage.  One prisoner believed they were finally successful in getting through the defenses, but apparently this feat accomplished nothing of any value.
	Three or four days later they received a message from Control ordering them to proceed to an area off the Coast of North Africa and they set course for Bone.
	Finally toward the end of September, after fourteen days at sea, a loaded eastbound convoy was sighted between Phillipeville and Bone and two torpedoes were fired from the bow tubes at periscope depth.  Two ships, one 7,000 and one 8,000 tons, were claimed sunk.  (O.N.I. Note:  On 30 September 1943 in position 37.19 N. – 06.40 E. two British ships, the EMPIRE COMMERCE of
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	3722 tons and the FORT HOWE of 7133 tons were sunk while in convoy MKS 26.)  After the attack U-410 went deep and broke off the engagement.
	Three or four days later a westbound convoy was sighted at night and five torpedoes were fired singly within five or six minutes.  Prisoners claim that out of five ships totaling about 56,000 tons, three ships totaling about 35,000 tons were sunk and two others damaged.  Although this claim is made by a number of prisoners of war no record of any sinkings in that area at this time can be found.
	U-410 returned to Toulon shortly thereafter, arriving sometime between 3 and 6 October.  While they were approaching the harbor, just outside the booms, U-410 rammed a German patrol boat and was badly damaged.  Her entire bow was stove in and all the bow tubes were badly damaged.  Fortunately for U-410, however, none of the torpedoes in the forward tubes, which were all loaded, were detonated.  The patrol boat was also badly damaged and was later torpedoed and sunk.
	The damage caused by this accident necessitated extensive repairs which lasted about four months, during which time complete new bow tubes were installed.  U-410 also increased her armament with the addition of two twin 20-mm. on Platform I and a quadruple 20-mm. on Platform II.
	During this extended docking period the crew went on leave twice, some for as much as eight weeks.  Rachner was transferred and Ritschel took over the duties of Engineering Officer.
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	CHAPTER XV SEVENTH AND LAST PATROL OF U-410
	U-410 left Toulon on her seventh patrol at 1900 on 2 February 1944.  She proceeded south and passed between Sardinia and the North African Coast on her way to her operational area, which was to be off Nettuno.  It was stated that U-boats never traveled between Corsica and the coast of Italy, due to danger of aircraft patrols.
	During U-410’s period in the Nettuno area, she would lay up during daylight hours about two miles west of Capri.  Though she would remain in a restricted area, U-410 would never bottom on these occasions.  At nightfall she would proceed somewhat westward, then surface to recharge her batteries and proceed north.  While operating off the Nettuno anchorage, Fenski stayed south of Anzio and 10-15 miles off shore.  On three occasions U-410 attempted to close the Nettuno anchorage, but each time a heavy smoke screen prevented her from getting into attacking position.  During this period also the weather was extremely bad.
	After having been on patrol for about ten days U-410 turned southward to operate off Salerno.  While at Salerno U-410 operated very close in shore, often at periscope depth and on 15 February 1944, shortly after her arrival in her new area, U-410 sank her first ship of this patrol.  A “Liberty” ship was seen coming out of the harbor and U-410 fired two T-5s from her bow tubes which struck the ship and sank it.  (O.N.I. Note:  On 15 February the British FORT ST. NICHOLAS of 7154 tons was sunk in
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	position 40.34 N. – 14.37 E.)  Following the “Liberty” ship out of the harbor was a 16,000 ton transport, but when it saw what had happened to the ship ahead of it, quickly turned and ran back into the harbor.  U-410 then dove to about 80/90 meters and cleared the area.
	About three-quarters of an hour later, after having heard the sinking noises of the ship they had just hit, “pinging” noises were picked up from an approaching destroyer and U-410 was soon under attack.  One or two patterns of six to ten charges were dropped causing a slight water entry in the control room and making it difficult to maintain trim.  U-410 then went to about 180 meters, but the water entry made the boat quite stern-heavy and it was necessary to blow some of the tanks.  Though this procedure must have caused some concern on the part of the crew, lest it again disclose their position to the hunting destroyer, all hands were relieved shortly thereafter to hear the destroyer give up the hunt and steam away.  The opinion of some prisoners was that the destroyer, hearing the tanks being blown, thought the submarine had fired a T-5 at them, and, therefore, got out of the way as fast as they could.  (O.N.I. Note:  No record of such an attack by an Allied vessel can be found.)  U-410 took this opportunity to surface and escape at high speed.  During the next twenty-four hours U-410 licked her wounds and tried to repair the damage to one of the trimming tanks which was torn open.
	The next morning, somewhere near the Island of Ischia off Naples, U-410 sighted a LST escorted by a PC boat and a
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	destroyer.  Bow tubes one and two were loaded with T-5, but after firing tube two, it was discovered that the other torpedo had failed to leave the tube.  After feverish efforts it was finally ejected with the aid of a small explosive charge, but it had apparently been damaged, as it failed to run correctly and just fell out of the end of the tube.  After a lapse of six to eight minutes a terrific explosion was heard.  (O.N.I. Note:  There is no record of this attack.)
	U-410 SINKS BRITISH CRUISER PENELOPE
	Early in the morning of 18 February 1944, U-410 while patrolling at periscope depth in the Gulf of Gaeta, sighted a British cruiser of the AURORA Class approaching Nettuno.  The cruiser was said to be proceeding at 28 knots with a 40 degree zigzag when the first torpedo, a T-3, was fired from tube No. IV at a range of about 800 meters.  A hit was scored, reducing the cruiser’s speed to about two knots.  Tube No. I, loaded with a FAT, set long at 1500 right gyro, was fired to administer the coup de grace, but it was a hot tube runner.  It was finally expelled, however, and a T-5 was fired from tube No. II.  This struck the cruiser amidships and she was said to have gone down in about two minutes. (O.N.I. Note:  The British cruiser PENELOPE was struck at about 0700 on 18 February in position 40.55 N. – 13.21 E.  She was traveling at 26 knots, zigzagging unescorted.  After the first torpedo struck she lost way and turned a complete circle to starboard.  She was still moving
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	slowly when the second torpedo hit about 15 minutes later and she sank in less than a minute.)
	After the attack, U-410 left the area at slow speed submerged and was not counterattacked.  That evening U-410 reloaded tubes No. II and IV with FATs and tested their gyro mechanisms.
	The next night, while operating off Nettuno, U-410 claims to have sunk a destroyer.  (O.N.I. Note:  There is no record of this attack.)
	A few days later U-410 returned to the Gulf of Gaeta and on 21 February 1944 shortly before dawn, they sighted a LST.  One torpedo was fired from tube No. II and an explosion was soon heard.  Tube No. IV containing a FAT set long with 250 right gyro was then fired and the LST blew up with a terrific explosion.  They felt it must have been loaded with gasoline as the mainland was illuminated by the blaze.  (O.N.I. Note:  The British LST 305 was sunk on 21 February in position 41.14 N. – 12.31 E.)  U-410 immediately surfaced and escaped at high speed.
	One week later, on 28 February 1944, U-410 made a triumphant return to Toulon and was received by the new Admiral U-boats, Mediterranean.  (O.N.I. Note:  Kapitän zur See Werner Hartman had recently replaced Konteradmiral Kreisch as Admiral U-boats, Mediterranean after his return from a cruise to the Indian Ocean as Commanding Officer of U-198, a 1200-ton U-boat in October 1943.)  Seven or eight Iron Crosses First Class were
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	awarded, as well as other decorations, and a three-day celebration followed.
	DAMAGE TO U-410
	During this stay in port, Toulon underwent two heavy Allied air raids on 6 and 11 March 1944.  It was during this latter raid that U-410 and another boat, U-380 under the command of Kapitänleutnant Albrecht Brandi, were hit and badly damaged.  The damage to U-410 was so extensive that all hope of putting back to sea was abandoned, at least temporarily, and most of her crew was transferred to U-371, which had returned from patrol about 25 March 1944.  U-371’s crew were sent back to Germany to commission a new boat.
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	CHAPTER XVI.  OTHER U-BOATS
	U-129         Now commanded by Oberleutnant Richard von Harpe.  Oberleutnant Hans Offermann formerly served as Executive Officer under Oberleutnant von Harpe and as Second Watch Officer under Kapitänleutnant Hans Witt.     U-188         U-188 commanded by Kapitänleutnant Seigfreid Lüdden and U-532, commanded by Korvettenkapitän Otto Junker, together with U-506+ and U-533+ left for the Far East on 6 July 1943.  U-188 and U-532 were in the South Atlantic on their return trip by late April or early May 1944.  U-188 had orders to refuel U-66+ on 3 May 1944 southwest of the Azores but never made the rendezvous.     U-407         Was confirmed by prisoners to be sunk.     U-411         Was commissioned early March 1942.  (O.N.I. Note:  Now sunk.)     U-455         Now commanded by Kapitänleutnant Hans Martin Scheibe.  Was commissioned in August 1941.  Left on patrol from Kiel 14 January 1942, operated off Iceland, but sank nothing.  Returned to Bergen end of March 1942.  Reported to have been in Toulon early March 1944.     U-532         See U-188
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	U-565         Commanded by Oberleutnant Fritz Henning.  Went to Salamis, November or December 1943.  (O.N.I. Note:  U-565 left Toulon 8/9 December 1943 and has apparently been operating from Salamis since then.     U-596         Commanded by Oberleutnant Viktor Nonn, is believed to be operating out of Pola.  (O.N.I. Note:  Information spring 1944.)
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	U-BOATS IDENTIFIED BY COMMANDERS
	U-BRANDI          A new boat, newly arrived from the Atlantic, with the Olympic Rings insignia was taken over by Kapitänleutnant Albrecht Brandi after U-380 was damaged.  This boat was in Toulon early March 1944.  (O.N.I. Note:  Kapitänleutnant Brandi was also reported to have a shore appointment in Toulon since the damaging of U-380.)     U-BREITHAUPT         A 500-ton U-boat commanded by Kapitänleutnant Wolfgant Breithaupt (now dead) left Kiel with U-410 and UD-3, 27 August 1942.  All three proceeded to Kristiansand.  (O.N.I. Note: U-410 was previously reported to have left Kiel early October 1942.  However, it was known that Breithaupt and UD-3 left on patrol late August 1942, hence the above would seem correct.)               U-Breithaupt, together with another U-boat, (O.N.I. Note:  According to previous information, U-410 picked up survivors from U-Gilardone, which was rammed and sunk in October 1942.     U-GEBHARDT         Oberleutnant Gebhardt (O.N.I. Note:  May be either Rudolf or Wilhelm Gebhardt, both of the October 1939 Term) was stated to command a U-boat in Toulon early March 1944.
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	U-HUTH           Oberleutnant Walter Huth left La Spezia 12 May 1943 at the time that U-410 arrived.  U-Huth was sunk on this patrol.     U-KOLBUS         Oberleutnant Hans Kolbus was reported to have operated in the Mediterranean March 1944.     U-RAHN         A U-boat commanded by Oberleutnant Wolfgang Rahn was stated to have been in Toulon early March 1944.     U-SIEGMANN         Kapitänleutnant Paul Siegmann was reported at sea late February 1944 with U-410.  He was damaged by aircraft and returned to Pola.     U-URBAN         Oberleutnant Hans Joachim Urban (1936 Term) entered the Mediterranean December 1943 or January 1944.
	U-BOAT IDENTIFIED BY COVER NAME
	SCHWARZE HAND         A U-boat with the cover name “Schwarze Hand” was in Toulon Easter 1944 (O.N.I. Note: 9 April 1944).
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	CHAPTER XVII.  BASES
	TOULON
	On 6 March 1944 there was a heavy air raid on Toulon.  Most of the bombs fell in the destroyer port and in the area of LaSenne.  The French Cruiser “JEAN DE VIENNE”, previously scuttled, but since refloated, was hit and severely damaged.
	On 11 March 1944 there was another heavy air raid.  Bombs fell in the U-boat repair yards and many fell in the city itself.  It was during this raid that U-410 and U-380 were hit.  Twelve to fifteen large fires raged uncontrolled in the city.  A 3000-ton freighter was sunk at anchor and the “JEAN DE VIENNE” was hit again and set on fire.  A 14,000-ton Italian passenger ship was burned out in drydock, and a 500-600-ton ship was sunk in the entrance to the harbor.
	No small U-boats were reported seen in the harbor at Toulon.
	COSTEBELLE
	It was reported that dock facilities were being prepared for small U-boats and that many workers were being shifted there for the job.
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	CHAPTER XVIII.  MISCELLANEOUS
	THE WALTERBOOT
	Construction of the Walterboot (according to one of the prisoners) has been abandoned because its propellant was considered too dangerous.  It is described as follows:  250-300 tons; crew of 12; three bow torpedo tubes (experiments had been made with four bow tubes and one stern tube); surface speed: over 30 knots; submerged speed: 17-18 knots; unable to be detected by Radar.  Purpose of the Walterboot was, according to the advertising given to it by DONITZ, to resurrect the U-boat arm.  One prisoner described the boat’s batteries as being “self-charging”; he was unable to give details.
	THE SPEERBOOT
	The Speerboot described as a 1000-tonner, somewhat longer than a 750-ton U-boat; fitted with six bow torpedo tubes (no stern tubes); 21-inch torpedoes; improved Diesels; faster surface and submerged speed than 750-tonners; prefabricated; crew of 28-30.
	THE WALTER TORPEDO
	(Originally designed for use by Walterboot) is smaller in length and diameter than the usual 21-inch type.  It is not known whether the Walter Torpedo has been abandoned.
	(O.N.I. Note:  Other sources have reported that the U-boat construction program has been taken over by the “Organization Todt”.  This organization is headed by Dr. Speer and it is, therefore,
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	possible that all boats built by the organization, both large and small, will be designated as “Speerboote”.
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	ANNEX   CREW LIST OF U-371 AND U.S. EQUIVALENTS   OF GERMAN NAVAL RANKS.       Name Rank    USN Equivalent         Korvettenkapitän Lieut. Commander   Kapitänleutnant Lieutenant FENSKI, Horst Oberleutnant z. S. Lieutenant (j.g.)  WAGNER, Erich Oberleutnant z. S. Lieutenant (j.g.) BRESSLER, Reinhard Oberleutnant z. S. Lieutenant (j.g.) MÜLLER, Walter Leutnant z. S. Ensign * RITSCHEL, Ferdnand Oberleutnant (Ing.)   Lieutenant (j.g.)             Engineering duties only SIEBERT, Bernhard Fahnrich (Ing.) Midshipman           Engineering duties only WOHLERS, Willi Obersteuermann Warrant Quartermaster ROSE, Josef  Obermaschinist Warrant Machinist BAUMGARTEN, Gerhard Obermaschinist Warrant Machinist STAUFFER, Friedrich Oberbootsmaat Boatswain’s Mate 2cl. BÖHM, Karl Oberfunkmaat Radioman 2cl. LABUSKE, Gerhard Obermaschinenmaat Machinist’s Mate 2cl.   VENNEKÜTTER, Heinrich Bootsmaat Coxswain   APPELT, Heinz Bootsmaat Coxswain   SCHNEIDER, Werner Funkmaat Radioman 3cl. * RITTER, (?) Maschinenmaat Fireman 1cl.   BATTKE, Werner Maschinenmaat  Fireman 1cl. * KÜHNE, (?)  Maschinenmaat Fireman 1cl.   MOTHS, Erwin Maschinenmaat  Fireman 1cl.   HÖHER, Helmut  Maschinenmaat Fireman 1cl.   STEIN, Heinrich Mechanikersmaat  Torpedoman’s Mate 3cl.   RAKOWSKI, Alfred  Sanitätsmaat Pharmacist’s Mate 2cl.   LANGOHR, Karl Heinz Matrosenobergefreiter Seaman 1cl.   WOLFF, Willi  Matrosenobergefreiter Seaman 1cl.   BEERBAUM, Arnold Matrosenobergefreiter Seaman 1cl.   SCHULZ, Norbert Matrosenobergefreiter Seaman 1cl.   KAPUTKE, Walter  Matrosenobergefreiter Seaman 1cl.   WINKELMANN, Herbert Funkobergefreiter Seaman 1cl.   KIEFER, Josef  Maschinenobergefreiter Fireman 2cl.   WEPPLER, Willi  Maschinenobergefreiter Fireman 2cl.   FRANZ, Freidrich Maschinenobergefreiter Fireman 2cl.     HAUSER, Richard Maschinenobergefreiter Fireman 2cl.   LENZ, Albert Maschinenobergefreiter Fireman 2cl.   DÖLLEIN, (?) Maschinenobergefreiter Fireman 2cl.   KREMMIN, Gunther Mechanikerobergefreiter Seaman 1cl.   NATZSCHKA, Roland  Mechanikerobergefreiter Seaman 1cl.   RAIDA, Ewald Mechanikerobergefreiter Seaman 1cl.   SPERLING, Franz  Mechanikerobergefreiter-A Seaman 1cl. (Gunnery)   RAAB, Hans Matrosengefreiter Seaman 2cl.   BOGDAN, Ulrich Matrosengefreiter Seaman 2cl.   ULBRICH, Erich  Matrosengefreiter Seaman 2cl.

 

	Name Rank  USN Equivalent           KÖNIG, Karl Matrosengefreiter Seaman 2cl.   PICKERT, Reinhard Matrosengefreiter Seaman 2cl.   BLUM, Walter  Funkgefreiter Seaman 2cl.   ROSER, Kurt  Funkgefreiter Seaman 2cl.   DINGES, Hugo  Maschinengefreiter Fireman 3cl.   WERNER, Heinz  Maschinengefreiter Fireman 3cl.   NÄTHER, Heinz Maschinengefreiter Fireman 3cl.   PROSSEK, Werner Maschinengefreiter Fireman 3cl.   MATTHEWS, Karl  Maschinengefreiter  Fireman 3cl.   BLOCK, Horst Maschinengefreiter Fireman 3cl.   REUTER, Heinrich  Matrose I Apprentice Seaman   LIPPOLD, Kurt   Matrose I  Apprentice Seaman           *Denotes dead.       (Ing.) denotes Engineering Duties Only.