Copy No. _46_ of 46.

                                                                                                                   S E C R E T

Op-16-Z

NAVY DEPARTMENT

OFFICE OF THE CHIEF OF NAVAL OPERATIONS

WASHINGTON

FINAL REPORT - G/Serial 34

REPORT  ON  THE

INTERROGATION  OF  SURVIVORS  FROM  U-177

SUNK  6  FEBRUARY  1944

DISTRIBUTION:

    BAD

    BUORD

    BUSHIPS

    BUSHIPS (Code 515)

    BUSHIPS (Code 815)

    COMINCH (F-21)

    COMINCH (F-4253)

    COMINCH (F-45)

    COMINCH (FX-40)

    COMINCH (FX-43)

    COMNAVEU

    ONI (Ottawa)

    G-2 (Col. Jones)

                                                                                                                           S E C R E T

TABLE OF CONTENTS

CHAPTER	I.		INTRODUCTION	1
	II.		DETAILS OF U-177	3
	III.		TECHNICAL DETAILS AND PROCEDURES	14
	IV.		GUNS AND AMMUNITION IN U-177	19
	V.		MOTORLESS OBSERVATION HELICOPTER ("BACHSTELZE") USED ON 1200-TON U-BOATS	35
	VI.		CREW OF U-177	47
	VII		EARLY HISTORY	54
	VIII.		FIRST PATROL OF U-177	57
	IX.		SECOND PATROL OF U-177	67
	X.		THIRD AND FINAL PATROL OF U-177	75
	XI.		SINKING OF U-177	79
	XII.		OTHER U-BOATS	84
	XIII.		HISTORY AND DETAILS OF U-195	92
	XIV.		GENERAL REMARKS ON U-BOATS	96
	XV		MISCELLANEOUS	100

ANNEX

CREW LIST OF U-177 AND U.S. EQUIVALENTS OF GERMAN NAVAL RANKS.

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ILLUSTRATIONS

Plate			Facing Page
I.		Complementation and Tank Plan of 1200-ton, type IX D-2 U-boat.	4
II.		Diesel and Electric Motor Rooms of 1200-ton, type IC D-2 U-boat.	8
III.		Superstructure of U-177 - Elevation and Plan.	8
IV.		F.K.W. Long Range Short Wave Transmitter.	18
V.		F.K.W. Transmitter - Remote Control Panel.	18
VI.		105-mm. Fuze Setting Key.	22
VII.		Automatic 37-mm. Gun.	24
VIII.		Automatic 37-mm. Gun. - Diagram of Automatic Mechanism.	26
IX.		Automatic 37-mm. Gun - Muzzle and Feed Details.	28
X.		37-mm. Projectile.	30
XI.		Helicopter in Operation.	36
XII.		Helicopter - Diagram	38
XIII.		Helicopter - Rotor Head and Blades.	40
XIV.		Operations of U-177 - First Patrol.	66
XV.		Operations of U-177 - Second Patrol.	74
XVI.		Anti-Escort Mine.	96

                                                                                                                      S E C R E T

S E C R E T

CHAPTER I.  INTRODUCTION

        The successful career of U-177, a 1200-ton U-boat ended abruptly in position 10⁰35' S. - 23⁰12" W. at 1029Z on 6 February 1944, 45 seconds after the explosion of depth-charges dropped with devastating accuracy by an Ascension-based P.B.4Y of VB-107.  The history of this U-boat is essentially that of the brilliant exploits of Korvettenkapitän Robert Gysae, of the 1931 Term, under whose command U-177 made two long patrols to the Indian Ocean, in the course of which Gysae was credited with the sinking of fifteen Allied ships, totaling 104,000 tons.  When sunk, U-177 was on her third patrol, under the command of Korvettenkapitän Heinz Buchholz, of the 1929 Term, who relieved Gysae in Bordeaux on 10 October 1943.  She had been at sea 35 days, and was again enroute to the Indian Ocean, where this time she was to carry out her patrol and then proceed to Penang for anticipated Far Eastern operations.

        Of the complement of 65 carried on U-177's final patrol, only the second and third watch officers, two petty officers and ten men survived.  The great majority were trapped in the rapidly sinking U-boat;  approximately twenty men escaped the boat, but six of these, including Buchholz, were killed on deck and in the water by subsequent strafing and bombing.  The 14 survivors reached an auxiliary life raft dropped by the attacking aircraft, and were rescued after 56 hours by U.S.S. OMAHA, which landed them in Recife, Brazil.  A preliminary interrogation was conducted in Brazil, and 13 survivors were transferred to an interrogation center in the United States.

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S E C R E T

        Buchholz, acting on explicit orders from Commander-in-Chief U-boats, had instructed his crew relative to deportment in the event of capture, with particular recommendations as to the manner in which enemy interrogators could be foiled by false and misleading statements.  While, in consequence, the progress of interrogation was impeded somewhat at the outset, prisoners' security under questioning relaxed swiftly, with salutary results.  No torpedo specialists were among the survivors.

        Of particular interest is the extensive use made by U-177 on her second patrol of the helicopter carried aboard.  Chapter V of this report offers a detailed, illustrated account of the construction, operation and maintenance of the helicopter, and of the training of naval personnel in its use.

        Other special features of this report are the detailed, illustrated analysis, contained in Chapter IV, of the new type automatic 37-mm. gun recently mounted on German U-boats, and an account of German U-boat operations in the Indian Ocean (Chapters VIII and IX).

        Attention is further invited to the diagrammatic drawings of the complementation and superstructure of U-177 (Plate I and Plate III).

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

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S E C R E T

CHAPTER II.  DETAILS OF U-177

DISPLACEMENT

        1200 tons.

TYPE

        IX D-2.

BUILDING YARD

        Deschimag, Bremen.

FLOTILLA

        12th Flotilla at Bordeaux.

FIELD POST NUMBER

        M-16669.

CALL LETTERS

        UHJ.

PATRON

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S E C R E T

(See Chapter VIII).  One of Gysae's crutches was carried on the bridge as a talisman, and U-177 was known to her crew as "U-KRÜCKE" (U-Crutch).

CAMOFLAGE

        None.  Dark gray paint over-all.

DIMENSIONS

        Length over-all - 87 meters.

        Beam               - 6 meters.

        Draft, fully loaded - 5.20 meters.

        Draft, unloaded - 4.50 meters.

        Pressure Hull (Diameter) - 5.60 meters.

        Pressure Hull plating, thickness of:  25 mm.

COMPARTMENTATION

        (See Plate I).

PRESSURE PROOF BULKHEADS

        Four, as follows:  (See Plate I).

        1.  Between forward torpedo room and petty officers' quarters

        2.  Between officers' quarters and Control Room.

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S E C R E T

        3.  Control Room.

        4.  Diesel Engine Room.

        5.  After Torpedo Room.

PERISCOPES

        (a)  On first and second patrols, normal equipment (one observation periscope, power turned, with fixed eyepiece; one hand-operated attack periscope).

        (b)  On final patrol, two hand-operated attack periscopes with elongation of 2 meters, permitting periscope depth procedure at 17 meters.  The power turned observation periscope was removed and the two new periscopes were fitted in U-177 at Bordeaux in November or December 1943.

TANKS

        (See Plate I.)

DIVING

        Depth Gauges

                (a)  "Papenberg" gauge in Control Room, graduated to 25 meters - for operation at periscope depth.

                (b)  Two pressure-spring type gauges graduated to 200 meters.

        Tested Depth

                90 meters.

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S E C R E T

        Periscope Depth

                On first and second patrols - 15 meters.

                On final patrol                    - 17 meters.

        Crash-Diving Time

                38 seconds to periscope depth at flank speed.

        Maximum Depth Attained

                140 meters (in deep dive tests).

BRIDGE ARMOR

        16-mm. armor plate fitted around bridge fairing.

        2 extra armor plates were riveted to the sides of the Conning Tower for delivery in Penang.

AIR RAID SHELTER ON BRIDGE

        Not fitted.

GUN PLATFORMS

        Two.  (See Plate III.)

ARMAMENT

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S E C R E T

                (3)  On last patrol - 26 or 27 (including four T-5a)  Distribution of the 24 torpedoes on U-177's second patrol was given as follows:

                Bow tubes - 4.

                Below plates, forward - 4.

                On plates, forward - 2 (1 port, 1 starboard).

                Stern tubes - 2.

                On plates, aft - 2 (1 port, 1 starboard).

                Upper deck containers - 10.

                (Corresponding distribution of torpedoes is believed to have obtained on the first patrol.)

                The 10 torpedoes in the upper deck containers were air-driven; the 14 in the boat were electrics.

                No F.A.T.'s of T-5's were carried on the first two patrols.

                Distribution of the 26 or 27 torpedoes carried on the last patrol was similar to that on the second patrol, except that 12 torpedoes were carried in the upper deck containers, and three torpedoes were on the floor plates aft.  16 or 17 torpedoes were T-1's and T-3.  Six or seven were F.A.T.-1's and F.A.T.-2's.  The distribution of the four T-5's carried was variously said to be:

                (a)  One in a stern tube.

                      One in a forward tube (Tube No. 1 or No. 3).

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S E C R E T

                      Two on floor plates aft (1 port, 1 starboard).

                (b)  Two in stern tubes.

                       None in forward tubes.

                       Two on floor plates aft.

                (c)  Two in forward tubes.

                       Two in after tubes.

                       None stowed.

                Pi-4 pistol was used with the T-5 torpedo.

MINES

        Never carried aboard U-177.

HELICOPTER

        (For detailed information on this subject see Chapter V.)

SCUTTLING CHARGES

        Carried but never installed.

WELDING EQUIPMENT

        Underwater welding equipment carried.

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S E C R E T

        Main Diesels

                2 M.A.N. 9 cylinder, 220 H.P. each with supercharging; 1500 H.P. without supercharging.

        Estimated speeds and R.P.M. (on both Diesels):

Full Speed	-	17 knots, 430 R.P.M.
4/5 Speed	-	15 knots, 405 R.P.M.
3/4 Speed	-	13 knots, 350 R.P.M.
Half Speed	-	11 knots, 300 R.P.M.
Slow	-	9 knots, 230 R.P.M.
Dead Slow	-	7 knots, 185 R.P.M.

        Auxiliary Diesels

                Two M.W.M. (Motoren Werke Mannheim) 6 cylinder, 500 H.P.

        Super Changers

                Büchi type fitted for main Diesels.

        Fuel Oil Capacity

                510 tons on final patrol.

       

        Electric Motors/Generators

                Two Siemens - Schuckert, 600 H.P. each.

        Auxiliary Generators

                Two Siemens - Schuckert.

        Switchboards

                Siemens - Schuckert.

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S E C R E T

COMPRESSORS

        Two Junkers compressors and 1 electric compressor.

COMPRESSED AIR SUPPLY

        Eight groups of 3 bottles each.

PUMPS

        (See Plate II.)

        (a)  Main bilge pump.

        (b)  Auxiliary bilge and trim pump (Control Room),

        (c)  Auxiliary bilge pump (forward Torpedo Room).

        (d)  Auxiliary bilge pump (after Torpedo Room).

        (e)  Auxiliary engine cooling water pump.

FRESH WATER STILLS

        (See Plate II.)

        Two - capacity of 32 liters each per day.

GERMAN ASDIC

        Not fitted.

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S E C R E T

off La Pallice shortly after departure.

G.S.R. (GERMAN SEARCH RECEIVER)

        Wanz G-2, 2 "Naxos" sets with 2 aerials, and a "Borkum" set were fitted for the last patrol.  (For details of these sets see G/Serial 30, U-231, pages 8, 13.)  On her first and second patrols, U-177 carried a metox R600 receiver with cross-type aerial.

        The fixed dipole aerial was mounted on the periscope support in the center of the bridge rather than in the usual position on the bridge fairing.

D/F GEAR (DIRECTION FINDER)

        Standard Lorenz M/F D/F set.

COMMUNICATIONS EQUIPMENT

        Transmitters

                (1)  Telefunken 200 watt H/F Transmitter, 20 to 80 meter wavelengths.

                (2)  Telefunken 200 watt F.K.W. (Fernverkehrskurzwellensender) H/F Transmitter, 13 to 100 meter wavelengths, fitted with separate remote control panel.  (See Chapter III, Plate IV and Plate V.)

                (3)  Telefunken 150 watt L/F Transmitter, 250-1500 meter wavelengths.

                (4)  Lorenz 40 watt emergency transmitter.

        Receivers

                (1)  "Main" short wave receiver (Telefunken).

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S E C R E T

                (2)  Telefunken all-wave receiver.

                (3)  "Elak" 10/12 broadcast receiver.

        U.T. (Underwater Telegraph)

                Fitted.

        U.K. Gear  (Ultra Short Wave)

               Fitted.  Lorenz manufacture.  (See Chapter III.)

        Broadcast Amplifier (40 watt)

                Fitted.

ROTARY CONVERTERS

        One 6 KVA for main transmitter and general radio purposes.

        One 1 KVA for hydrophones and U.T.

        One 0.3 KVA for echo-sounder and gyros.

        The 0.3 and 1 KVA converters could be used interchangeably.

HTDROPHONES

        (a)  "Atlas" G.H.G. multi-unit hydrophones fitted.

        (b)  K.D.B. removed after second patrol.

ECHO SOUNDER

        "Elaklot" fitted.

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S E C R E T

        (4)  Diesel Engine Room.

        (5)  Electric Motor Room.

        (6)  Radio Room.

        (7)  Sound Room.

        A repeater connection was also fitted in the after Torpedo Room.

AIR PURIFICATION

        (a)  "Klima-anlage" air conditioning system, capable of reducing humidity by 1.5 per cent per hour.  Non-cooling.

        (b)  "Kalipatronen" potash cartridges carried.

LIFE-SAVING AND ESCAPE GEAR

        One inflatable rubber dinghy carried.  Standard life jackets and escape lungs carried.

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S E C R E T

CHAPTER III.  TECHNICAL DETAILS AND PROCEDURES

TANK CAPACITIES (IN LITERS) OF TYPE IX D-2 U-BOATS

        (See Plate I)

Fuel Oil Tank 1a - Port:    22,000 liters;    starboard:    22,000 liters.

Fuel Oil Tank 2a - Port:    24,000 liters;    starboard:    24,000 liters.

Main Ballast and Reserve Fuel Oil Tank #2 - Port:    28,000 liters;    starboard:    28,000 liters.

Main Ballast and Reserve Fuel Oil Tank #3 - Port:    28,000 liters;    starboard:    28,000 liters.

Main Ballast and Reserve Fuel Oil Tank #4 - Port:    31,000 liters;    starboard:    31,000 liters.

Regulating and Reserve Fuel Oil Tank - Port:    18,000 liters;    starboard:    18,000 liters.

Main Ballast and Reserve Fuel Oil Tank #6 - Port:    27,000 liters;    starboard:    27,000 liters.

Main Ballast and Reserve Fuel Oil Tank #7 - Port:    24,000 liters;    starboard:    24,000 liters.

Fuel Oil Tank 3a - Port:    22,000 liters;    starboard:    22,000 liters.

Fuel Oil Tank 4a - Port:    24,000 liters;    starboard:    24,000 liters.

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S E C R E T

Auxiliary-Motor Oil Collecting Tank - Port:    800 liters;    starboard:    800 liters.

Diesel Engine Fuel Oil Gravity Tank:    1800 liters.

Junkers Compressor Fuel Oil Gravity Tank:    50 liters.

Lubricating Oil Tanks for Superchargers:    Port:    60 liters;    starboard:    60 liters.

Container for Lubricating Oil for Days Use-Lubricating Engines:    30 liters.

Torpedo Compensating Tank #1:    2500 liters.

Torpedo Compensating Tank #2:    2500 liters.

Torpedo Compensating Tank #3:    5000 liters.

Torpedo Compensating Tank #4:    5000 liters.

After Trimming Tank:    4500 liters.

Forward Trimming Tank:    4500 liters.

Fresh Water Tanks #1:    900 liters;    #2:    1000 liters.

Fresh Water Tanks #3:    900 liters;    #4:    900 liters.

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S E C R E T

of, and not connected to, the main Diesels.  They served exclusively to drive 2 small generators, each of which had its own switchboard distinct from the main switchboard.

        It was stated that the use of these auxiliary Diesels simultaneously with the main Diesels would reduce the time required for charging batteries by 2 hours.  Also, the output of the auxiliary generators was sufficient to provide current for the main electric motors to run at 250 R.P.M. without any drain on the batteries.  When desired, the current from the auxiliary generators could be fed to the electric motors while the main Diesels were running.  This reduced the load on the main Diesels, which could then be run 50 R.P.M. faster than otherwise.

        The auxiliary Diesels were 400 H.P. - 700 to 750 R.P.M.  They were connected to the auxiliary generators by a direct drive.  They had separate exhaust valves and separate mufflers, and were not fitted with superchargers.

        Exhaust temperatures for the main Diesels at flank speed are 470⁰ to 480⁰ Celsius - for the auxiliary Diesels 390⁰ to 420⁰ Celsius.  The general layout of cooling, lubricating, and fuel lines in U-177 was in all respects similar to that in H.M.S. GRAPH (ex U-570).  The only differences are illustrated in Plate II.

SERVICING OF T-5 TORPEDOES

        Every two days, each T-5 was partially withdrawn from the stern tubes.  After a plug on the tailpiece had been removed, a whitish-yellow colored oil was poured into the opening.  The purpose

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of the oiling, which was also done to the two acoustic torpedoes stored on the floor plates aft, was to insure a more silent-running torpedo.

F.K.W. (FERNVERKEHRSKURZWELLENSENDER)

        (See Plate IV and Plate V.)

        This is fitted into all 1200 ton U-boats, in addition to the 200 watt short-wave transmitter (20 to 80 meters wavelength) and the 40 watt emergency transmitter.  The FKW is also 200 watts, but transmits on wavelengths from 13 to 100 meters.  It is fitted with a separate EBG (Einheitsbetriebsgerät) (remote control panel).  On U-177 the FKW was generally used, rather than the 200 watt Telefunken transmitter.  Two 200 watt transmitters are carried because these boats operate so far from home that, in case of a breakdown of one of the transmitters the other can be used, the 40 watt emergency transmitter having insufficient power.

        It was confirmed that, although U-boats operating west of Capetown and in the South Indian Ocean receive signals from Control on "AFRIKA II" Schaltung (Series) they are free to transmit on any "Schaltung" (Series) i.e. Frequency, which is being satisfactorily received by Control.

        It was stated that there is an area of very bad reception around 05⁰ S. and between 18⁰ and 22⁰ W.

        Reception was very bad during all daylight hours, once they had passed east of Capetown.  After dark, however, reception was excellent on both short and long waves.

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S E C R E T

U.K. (VH/F) GEAR

        This was fitted with a telephone receiver, comparable to equipment carried in U-172.  (O.N.I. Note:  See G/Serial 29, U-172, Chapter II.)  It had been built in before the last patrol, and had never been used.  A survivor believed that all U-boats are now fitted with this gear, which is intended to be used for voice traffic with cooperating aircraft.  When in use, it is connected to the "Stabsantenne" (Rod aerial), through the "Antennewahlschaltafel" (Aerial selector panel).

BORKUM G.S.R.

        This is primarily intended as emergency gear in case of breakdown of the Wanz.  It is never used simultaneously with the Wanz, since both of these have to be connected to the "Rundipol" (Basket type aerial) when in use.  It is used regularly, however, in order to "rest" the Wanz, which is subject to overheating.  While one survivor was not sure just how Wanz operates, the thought the automatic scanner is most subject to overheating, and stated that after about one hour's operation the outer case of the Wanz becomes so hot that it is impossible to touch it.  Prisoners expressed great contempt for all G.S.R. equipment.  (See Chapter XIV.)

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S E C R E T

CHAPTER IV.  GUNS AND AMMUNITION IN U-177

DECK ARMAMENT

        First Patrol - One 105 mm. gun forward of Conning Tower.

                            One 20 mm. single on bandstand.

                            One 37 mm. gun (old type) on deck aft.

        Second Patrol - One 105 mm. gun forward of Conning Tower.

                                 Two single 20 mm. guns on bandstand.

                                 One 37 mm. (old type) on deck aft.

                                 Three M.G.-15s (demountable) on bridge.

        Third Patrol - One 105 mm. gun forward of Conning Tower.

                              Two 20 mm. twin mounts on Platform I.

                              One new 37 mm. automatic gun on Platform II.

                              Four demountable M.G.-15s.

AMMUNITION CARRIED ON THIRD AND LAST PATROL

        105 mm:  U-177 carried 200 rounds of ammunition for this gun.  There were 65 rounds of H.E. packed in gray containers with brown and yellow marking, 65 rounds if incendiary  shells in containers marked with a red ring, and 70 rounds of "Zonenmunition" (H.E/A.A. shells) in gray containers with red markings.  "Zonenmunition" rounds had yellow markings with black lettering.

        In ready-use lockers were 38 rounds of incendiary and H.E., mixed.  The rest of the ammunition for this gun was stored in the magazine.

        20 mm:  8000 rounds of 20 mm. ammunition were carried.

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S E C R E T

        There were three types; mixed in more or less equal proportions:

                A/P with tracer - pointed nose, blue with red ring.

                H.E. with tracer - yellow markings, red ring.

                H.E. without tracer - yellow only.

        The last two types had aluminum fuze head, nose somewhat flattened.

                There were 13 clips containing 18 rounds each in ready-use lockers, 48 clips of 18 rounds each in the Conning Tower, and 60 clips of 18 rounds each in the magazine.

                Two clip-loaders were carried, but only one was ever used.  These were for 20 mm. ammunition only.  They were said to be very noisy but very fast.

        37 mm:  Only one type of ammunition was carried for the 37mm. gun.  This was called "Minenmunition" (mine munition).  It is believed to be H.E.  Projectiles were painted yellow with red markings.  The aluminum fuze head was not painted.

        Clips of 5 rounds each were loaded by hand, no loader being supplied for the "Minenmunition".

        In Bordeaux U-177 took aboard 40 water-tight containers of 25 rounds each.  In La Pallice 47 additional containers, likewise of 25 rounds each, were supplied to the boat.  In addition to the above containers, all of which were stored in the boat, there were about 375 rounds in clips, of which 250 were in upper deck containers.  These containers had a maximum capacity of 280 rounds.

DETAILS OF THE VARIOUS GUNS

        105 mm.:  Elevation 65 degrees, depression 10 degrees.

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S E C R E T

        The gun could be elevated to 70 degrees after loading.  Loading at 70 degrees was impossible because at this angle there was not room enough between the breach and the deck to insert the round.

        H.E. and incendiary ammunition were used against ships; the "Zonenmunition" (also "Fliegermunition") was primarily for use against planes, but could also be used against surface targets.

        The fuze of the "Zonenmunition" can be set by means of a key (See Plate VI.)  For general purposes two settings are used:

        (a)  Nahzone (near zone) - 2,2 - about 2000 meters.

        (b)  Weitzone (distant zone) - 4,8 - about 5000 meters.

        Fuzes are so set either in port or at sea at the discretion of the commanding officer.  These general-purpose settings apply only when there is no time to set the fuze for each round as it is passed to the gun.  Ideally, each round will be individually set.  By this means, it is claimed, a perfect barrage can be set up.  Settings can be made as high as 7500 meters.  Fire is opened, however, when the attacking aircraft approaches the 10,000 meter zone.

        When the projectile explodes, concussion effect is great, causing air-pockets and, in the words of one prisoner "making the pilot nervous".  When a hit is scored, the explosive force is said to be extremely great.  Splinter effect has a wide range.

        Muzzle velocity, 650 meters per second; end velocity 500 meters per second.

        There were no shields for the protection of the gunners.  The usual ammunition chute from the bridge was fitted.

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S E C R E T

        20 mm:  No shields were provided for the protection of gunners at the twin mounts.  Ammunition was passed by hand.  All ammunition self-destroying at 2000 meters.  Tracer to 1800/2000 meters.  Loading sequence stated to be one A/P, one H.E. with tracer, one H.E. without tracer.  Rate of fire, 60 to 80 rounds per minute per barrel.  Eight extra barrels were stowed in the magazine.

        M.G.s:  It was stated that the M.G. 81 twin is no longer in use on U-boats, since it did not prove very successful for marine use.  There were many instances of failure to function.  The M.G. 15, on the other hand, is still very popular.  The rate of fire is fast, and cleaning and servicing are comparatively simple.  U-177's four machine-guns were never taken topside during her last patrol.

        Small Arms:  U-177 had the following small arms on board, stored in part in the magazine, part in the Control Room:

                3 Sub-machine guns (MP-40, possibly one of the newer model).

                7 Mausers (7.65).

DETAILS OF THE NEW 37 MM. AUTOMATIC GUN

        The new 37 mm. full-automatic gun was introduced to the U-boat arm about November 1943.  There is still no definitive manual for this gun.  Improvements will continue to be made as operational experience indicates their necessity.

        1.  WEIGHT - about 250 kilograms.

        2.  LENGTH OF BARREL - 3800 mm.

        3.  MUZZLE VELOCITY - 760 meters per second.

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S E C R E T

        4.  RANGE - Ammunition self-destroying at 4800/5000 meters.

        5.  TRACER - One gunner stated that the round has tracer to 4800/5000 meters.  An officer stated that tracer begins after 1-1/2 seconds and burns for 5 to 6 seconds, average velocity being 700 meters per second.

        6.  CEILING - Stated to be 3800 meters.

        7.  RATE OF FIRE - Theoretical, 100 to 120 rounds per minute.

                                          Practical, 50 to 60 rounds per minute.

        8.  SIGHTS - Ring and Bead.  Demountable.  Telescope sight can be substituted.  Sights can be folded back to prevent their being broken off when the boat submerges.

        9.  AMMUNITION - Fixed.  "Minenmunition", H.E. with tracer.

        10.  ROUNDS IN MAGAZINE - Five.

        11.  COLOR OF TRACER - Orange.

        12.  FLIGHT IN FIRST SECOND - 700 meters.

        13.  OPEN FIRE - When plane is 4000 to 5000 meters away.

        14.  WEIGHT OF ROUND - Two kilograms.

        15.  DETONATION - Impact.  Has aluminum fuze head.  Explodes on impact with water or lighter materials such as wood.  Self-destroying at 4800/5000 meters.

        16.  WATER TIGHTNESS - There is no provision for keeping water out of the barrel or the automatic mechanism when the U-boat submerges.

        17.  BREECH BLOCK - Vertical sliding wedge type.  Said to be of light metal alloy.  (Other parts of steel, or nickel-chrome steel.  Receiver of cast iron.)

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        18.  TRAIN - Unlimited.  Training mechanism on left side.  Hand wheel geared to training circle.

        19.  ELEVATION 90 degrees.  Elevating gear on right side.  Hand wheel geared to elevating arc.

        20.  DEPRESSION - 10 degrees.

        21.  RATE OF ELEVATION - From 10 degrees to 90 degrees in approximately 45 seconds.

        22.  RATE OF TRAINING - Complete circle in 10 seconds or more, depending upon how heavy the sea is.

        23.  GUN CREW - Five men:

                No. 1 - Trainer (seated).

                No. 2 - Pointer (gun fired by pointer) (seated).

                No. 3 - Breech (loader).

                Nos. 4 and 5 - Ammunition passers.

        24.  TIME TO PREPARE GUN FOR FIRING - When the U-boat is on the surface and the men are on deck, the gun can be put into operation in 1-1/2 minutes.  When the boat has been submerged and surfaces, 3 minutes will elapse before the first shot is fired.

        25.  TIME TO SECURE GUN FOR DIVING - 60 seconds.

        26.  DIMENSIONS OF SHIELDS - 1500 mm. by 1000 mm.  Thickness 15 50 20 mm.

        27.  NIGHT USE - Sights have luminous paint.

        28.  LENGTH OF RECOIL - 180 mm.

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        30.  LOADING - The gun is loaded from the top, above the automatic mechanism.

        31.  HEATING OF BARREL - It was stated that the gun could be fired for as long as 20 to 25 minutes continuously without excessive heating.

        32.  MEANS FOR REDUCING WATER RESISTANCE - Both shields are folded forward and the gun is secured.

        33.  MEANS FOR PREVENTING FIRING INTO OWN BOAT - A guard rail prevents firing into structure forward of gun platform.

        34.  RAMMER - Chain operated, actuated by a spring which is compressed by the recoil of the gun.

        35.  DISADVANTAGES - The gunner under interrogation stated that the chief disadvantage of this gun is that it requires too much servicing -- 25 to 30 minutes daily.  The ammunition must also be handled very carefully.

        36.  EXPLOSIVE - The prisoner could not remember just what the explosive charge is, but remembers hearing a term like Hexanitrodiphenilamin.

        37.  STARTER AND BREAKER - There are two buttons on the upper part of the cover.  One is the breaker, which interrupts the firing.  The chain is stopped and further firing is impossible.  The second button is the starter, which must be pushed down with much pressure and released immediately.  If this starting button is pushed down slowly, jamming occurs and the button cannot be released; at the

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same time there is danger that the rammer chain may no longer be under tension.  Assuming that the starting button is pushed down and released correctly, the rammer chain then rams the shell into the breach (as described below).  The starting button is to be used only once if there are enough shells, but should the shells run out, the gun must again be cocked.

        38.  PEDAL FIRING MECHANNISM - On the right side is a pedal operated by the pointer.  When the gun is ready to fire and the command to open fire is given, the pedal is pressed.  By means of a linkage, the trigger arm is actuated and the firing pin springs forward causing the gun to fire.

        39.  COCKING THE GUN - The hand cocking lever is shown at e, Plate VII, is forcibly pushed forward.  This operation requires the combined strength of two men.  The lever opens the breech by moving the breech block downward, at the same time causing the firing-pin spring to be engaged; simultaneously the cogged arc at the right (on the lower drawing on Plate IX) moves around to the right, pulling with it the wire or cable which is attached to the little pin shown at the forward end of the spring which is above the chain.  The wire or cable pulling on the pin causes the spring to be rammed backwards within its cylindrical housing.  The spring then remains under tension until the starter button is pressed.

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        40.  FIRING - When the gun has been cocked and the breech opened as described above, No. 3 inserts the clip containing five rounds and lets if fall by its own weight.   At a point about two-thirds of the length of the guide rail, the clip, which slides in a grove, falls out.  About 10 rounds can be inserted.

        Next the starting button is pressed, releasing the spring which forces the ramming chain forward.  At the same time the knob on the chain catches on the end of the case and carries the round forward and rams it into the breech.  At the same time the end of the case is grasped by the extractor which is now in vertical position.  The breech block is now free and moves upward and the breech is closed.

        The breech is now closed and the firing pin is under spring tension.  The gun is ready to be fired.  The pedal is depressed by the pointer; this releases the firing pin which snaps forward (by means of spring tension) and fires the gun.

        The force of recoil causes automatic reopening of the breech.  The ejector, which is bedded on springs, at this time throws the case out aft.  The case falls to the deck.

        Once fire has been opened, recoil forces operate all of the automatic mechanism, the various parts of which are all geared together by means of cog-wheels (not all

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of these cog-wheels are shown in any of the drawings).

        41.  RAMMER CHAIN - The rounds are inserted in the middle of the receiver cover and fall onto a tray which is likewise in the middle of the automatic mechanism.  On the left side of and above this tray is the rammer, which, therefore, is situated beside the round.  The rammer operates in such a way that the shell is grasped by the rammer knob from one side only.  Experience has shown no disadvantage in this -- i.e., the round does not get too far to the right.

        The chain is about 1300 mm. long and 12 mm. wide.  It is just like a bicycle chain.  The chain is removable by opening the fastening which holds the parts of the chain together.

        42.  PREPARING THE GUN FOR FIRING - Three men are necessary.  No. 1 releases side lashings, puts up trainer's sights, opens left shield into position, and takes trainer's seat.  No. 2 snaps right shield into position, releases elevation lashings, puts up pointer's sight, takes pointer's seat, and operates firing pedal.  No. 3 operates the hand cocking leaver, thus putting under tension the breech block and ramming mechanism.  Then he inserts the clip, pushes the starting button which shoves the round into the

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breech.  No. 3 also clears in case of jamming.  Two other men are necessary as ammunition passers to insure rapid fire.

        43.  SECURING FOR DIVING - No. 3 pushes the breaker button so that the gun stops firing, the chain having been arrested.  Immediately the dog-lever is moved and remaining rounds are removed.  The breech is then closed by means of the breech-opener.  The starting button is pushed and the chain is thus slacked.  Then No. 2 "fires" with the pedal once more and tension of the firing spring is released.  Nos. 1 and 2 secure the gun against movement, shields are secured and sights are secured in horizontal position.

        44.  RECOIL - Prisoners were rather vague as to just what parts of the gun recoil, and stated that the automatic mechanism does not recoil, but only the barrel, and specifically everything forward of the first vertical line forward of the shields, as on Plate VII, view from left.  Within the receiver, along top and bottom, are the four recoil and counter-recoil springs.  At left top and right bottom of the receiver are the recoil brakes (hydraulic and spring); and at right top and left bottom are the springs for counter-recoil.

        45.  BREECH BLOCK - Dimensions of the breech block are approximately 10 cm. x 10 cm. x 17 cm.  Top surface

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is concave.  No special housing.

        The movement of the breech block is inaccurately shown in the drawings.  In downward movement, the breech block does not follow an exactly vertical line as indicated, but rather a diagonal line, being farther forward at lowest position.

        The lever or arm shown attached to the breech block in Plate IX has an arrangement of catches which automatically compress the spring behind the firing pin whenever the breech block is lowered.  The spring is released by the pedal, which, when depressed, disengages the catch as shown on Plate X, drawing No. 3.

        46.  BREECH OPENER FOR JAMMING - On Plate VII, at d, is a four-sided bolt to which a wrench can be applied in case the gun jams.  By turning this, one can move the breech block to its lowest position and open the breech.  This has nothing to do with firing the gun or cocking it.

        47.  SERVICING - The gun must be cleaned daily.  Cleaning takes 20-25 minutes except for the automatic mechanism, and the barrel, all parts are greased.  The automatic mechanism is covered with light oil by means of a brush.  A wire brush is run through the barrel, then an oiled brush is run through.  If this is done carefully there is no question of rust starting in the barrel.

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Complete overhaul is made once a week, i.e., all parts are inspected and lubricated.  The automatic mechanism is taken apart and examined, re-oiled and re-assembled.

        During U-177's passage through the Bay of Biscay, care of the guns was a difficult matter.  All the guns had to be serviced in the short time that the U-boat was on the surface.  When the Bay had been safely passed and there was time for adequate servicing of the guns, it was found that the 37 mm. gun was in very bad shape.  Careful and thorough overhaul and lubrication restored the gun to usefulness.  Daily firing practice was instituted, but there were many instances of jamming.  It was found that the grease that had until then been used for all parts of the gun, including the automatic mechanism, was to blame.  From then on, the thin oil, applied with a brush, was used for the automatic mechanism.  This was found to be much more satisfactory, jamming occurring much less frequently during daily firing practice.

        48.  BORE - Prisoners stated that the bore does not taper.  It has 8 lands and 8 groves.  The rifling (to the right) was stated to be quite unlike that of other guns: the spiral is much tighter, causing more turns of the projectile.  For this reason prisoners

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believed that there were as many as 10 to 15 turns in the rifling.

        49.  DETAILS OF ROUND - The case is made of light metal alloy.  Aluminum is one of the constituents of the alloy.  The alloy oxidizes easily when allowed to become wet with sea water.  Therefore, the case is kept oiled.  If water splashes onto the case, it is wiped off as soon as possible and oil is applied.  The same thin oil is used for this as for the oiling of the automatic mechanism.  This oil was borrowed by the gunner from the engine room.

        Rounds were stated to be pressure proof to a depth of 30 meters.  If the rounds are left unprotected on deck and the U-boat submerges to a depth of less than 30 meters, it is not necessary to throw away the rounds; they must, however, be put aside until the case has been thoroughly wiped and re-oiled.  If the U-boat goes to a depth of more than 30 meters, water is forced inside the rounds, usually through the aluminum fuze head, and the rounds must be thrown away.

        The diameter of the case at the after end is about 50 mm.  Near the forward end, the case tapers to a diameter of 37 mm.  Length of case is about 330 mm.  The case is not painted.

        The projectile is 37 mm. in diameter at after end.

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The visible part of the projectile (in complete round) is about 100 mm. long.  At the forward end, the projectile tapers to the aluminum fuze head (included in above measurement.  The fuze head itself is about 20 mm. long).  The projectile is painted yellow and has some red figures or markings on it, these indicating reddish or orange colored tracer.  The aluminum fuze head is not pointed but flat.  The head has two notches for a key by means of which the fuze can be unscrewed.  This was never done aboard U-177.

        The complete round is about 430 mm. long.

        50.  RESERVE BARREL - One reserve barrel was carried in a container on Platform II under the starboard ladder.  One more barrel was stowed in the Control Room.

        51.  RESERVE AUTOMATIC MECHANISM - One, carried in the Control Room.

        52.  IDENTIFICATION MARKING - The barrel of U-177's 37 mm. gun bore the following, molded in the side: b.y.v.43.

        53.  ESTIMATE OF THE GUN - The gunner who furnished much of the above information said that changes will have to be made before the gun is really suitable for use in U-boats.  For one thing, the loading of rounds is difficult when the gun is at extreme

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elevation, and feed may be interrupted.  He also stated that far too much servicing is required.  An officer believes that the gun is useless for U-boats because of the delicacy of its mechanism and numerous breakdowns.  The weakest point is the rammer chain, he says.  In his opinion it will soon be abandoned.

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CHAPTER V.  MOTORLESS OBSERVATION

HELICOPTER ("BACHSTELZE") USED ON 1200-TON U-BOATS

        U-177, in common with certain other 1200-ton German U-boats used a small motorless helicopter known as a "Bachstelze" (Water Thrush) for the purpose of observation at a considerable height.  The helicopter is demountable, its parts are stored on board, and it is assembled on deck when the Commanding Officer orders an ascent.  In flight, it is towed by the U-boat.  The following account gained from survivors, illustrated by scale drawings, gives details of pilot training and an analysis of advantages and disadvantages of the apparatus.

CONSTRUCTION

        The helicopter is constructed almost entirely of light metal stated by prisoners to be aluminum.  The blades of the propeller and empennage or tail parts are constructed of wooden staves with cloth covering and airplane "dope" on the outer surface.  The parts of the helicopter are as follows:

        Rotor Head with Blades.

        Handle for Releasing Rotor and Blades.

        Strut Wires.

        Parachute Rip-chord.

        Rudder Pedals.

        Instrument Board.

        Tow-cable.

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        Control Stick.

        Pilot's Seat.

        Flexible Cable from Tachometer to Rotor Head.

        Landing Surfaces.

        Tubular Fuselage.

        Parachute.

        Fixed Stabilizing Rudder.

        Moveable Rudder.

        Rotor Blades.

        Instrument board with Altimeter, Speedometer, and Tachometer.

        Pitot tube.

        Fixed Horizontal Stabilizers.

        The pressure proof containers in which this helicopter is carried on board the U-boat are built into the Conning Tower.  It is extremely important that these compartments remain water-tight since, if sea water were to reach the helicopter, it would be rendered unfit for operation, through damage to instruments and possible warping of the wooden parts.  A third pressure proof container houses a winch, to which is attached a 300-meter cable used for towing the helicopter in the air.  The fuselage is stored in the portside container, and propeller and tail assembly are stored in the starboard container.

        In order to insure replacement of the parts of the helicopter, the U-boat carries two complete machines; thus, if

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the one in use - or any part of it - is damaged and unfit for use, it is replaced by the second one, which is stowed in the pressure hull.  The second helicopter is not assembled and the parts are usually stored as follows:

        1.  The extra fuselage is placed in the starboard engine room.

        2.  The blades of the extra propeller are stored in the electric motor room.

        3.  The three extra propeller blades which are usually carried in addition to those belonging to the two complete helicopters are, as a rule, stored in munitions room #2; sometimes they are stored in the Petty Officers' room.

       4.  An extra telephone box is also stored in the electric engine room.

THE FUSELAGE

        The fuselage consists of an aluminum pipe about four meters in length which has an outside diameter of 100 mm. and an inside diameter of 90 mm. with walls about 9.5 mm. in thickness.  In the front part of this hollow fuselage are located the cable connections for the steering apparatus and the telephone connections.  The steering cables which are connected to the foot controlled rudder run on pulleys along the hollow fuselage and are connected to the rear tail fins (see approximate placement of rollers or pulleys over which these cables run in Plate XII).  The telephone wire is connected to the tow-cable and has an outlet in the fuselage at the point where

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the pilot's seat is connected to the fuselage and carrier.  The cable connected to the joy stick runs through the fuselage and then by means of pulleys runs up the hollow vertical tube or carrier which holds the rotor head in the propeller blades.  In this way, the pitch of the propeller is controlled.  It will be  noted that the propeller blades are fixed in relation to the rotor head; there is no pitch control of the individual blades.  The entire rotor head is tilted forward or backward and from left to right.  With such a control, the head with the propeller blades can be tilted into the wind (top forward) and the revolutions per minute reduced thereby; or it can be lifted up and the wind will then increase the number of revolutions per minute.  Through this simple principle the helicopter rises or descends in direct proportion to the number of revolutions of the propeller per minute.  Atop the fuselage is the pilot's seat, which is attached just in front of the vertical tube or carrier containing the controls for the rotor head.  The pilot is strapped on to the seat by means of a quick-release type of shoulder harness and a belly girdle.  To the rear of the seat is the horizontal surface of the empennage; it is fixed and cannot be controlled.  In other words, there are no elevators on the tail assembly.  Atop the horizontal element is the fixed vertical fin.  To the rear of this is attached the movable tail fin, or rudder, which is connected to the cables running through the hollow fuselage from the foot control pedals in front of the pilot's seat.

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THE CARRIER

        The carrier is the vertical pipe which holds the rotor head and the propeller blades.  It is about 1-1/2 meters in length.  In the upper end is a spindle in which the rotor head is set, though the exact method by which the rotor head is connected to the carrier and the controls have not been established.  Within the vertical tube are the cables which are attached to the joy stick, the exact construction of which is also not known to survivors.

        Just to the rear of the pilot's seat and to the rear of the carrier is an attached parachute, the rip cord of which is attached to the rotor head.  Directly above the pilot's head is a release lever.  A sharp pull on this lever will release the entire rotor head with propeller attached.  As the rotor head falls off, it pulls the rip chord and the parachute opens.  It was stated that there is no danger of the propeller hitting the pilot as the helicopter almost always flies with the tail low.  As the parachute opens, the helicopter, minus the rotor head and propeller, will sink gently with the pilot to the surface of the water.  The pilot must free himself from the helicopter as soon as it hits the water, and utilize his life jacket to remain afloat.

THE ROTOR HEAD AND PROPELLER

        The rotor consists of a head with insert bosses into which the propeller can be inserted and bolted fast.  Since the propeller blades are large in comparison to the rest of the machine, it is necessary that they be supported; therefore, there are cables running

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from the top point of the head of the middle of each blade of the propeller.  Furthermore, there are strut wires running from one blade to the other which give the relatively flimsy propeller assembly some stability.  There are six of these stabilizing strut wires.  The propeller blades consist of wooden ribs about 25-30 cm. wide.  Each blade is covered with airplane cloth material, perhaps linen, and heavily doped.  The blades are about three meters in length.  It will be noted that the tips of the blades are rounded; and the other end is the "attach-on" which is inserted into the rotor head and holds the blade fast.

THE EMPANNAGE

        The empennage, like the blades of the propeller, is constructed of wooden ribs, covered with linen, and heavily doped.  The leading edge of the horizontal fin is fastened directly onto the fuselage while the trailing edge is held in position with a bolt and, possibly, a spring washer.  The horizontal fin is fixed and cannot be controlled.  It is approximately 700 mm. wide and about 1500 mm. long.  The vertical tail fin has the same construction also, and is firmly attached above the horizontal fin.  Attached to this vertical fin is the movable rudder which enables the pilot to control, within limits, the flight of the machine.  Through the use of this rudder, it is possible for the helicopter to weave from side to side behind the U-boat, within an arc of about 60⁰.

THE INSTRUMENT BOARD

        The small instrument board or panel contains the following three instruments:  (1)  Altimeter; (2)  Speedometer;  (3)  Propeller

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Tachometer.  The altimeter is the regular sensitive aneroid type.  The speedometer is operated by means of a pitot.  The tachometer for the propeller is operated by a flexible cable extending from the rotor spindle through the carrier and the hollow fuselage to the tachometer.

THE PILOT'S EQUIPMENT

        The pilot's equipment consists of the following:  (1)  A combination telephone (transmitter and receiver) built into an aviator's helmet; by means of this, the pilot is in constant communication with his U-boat and can arrange the altitude of his flight by giving orders for the release or retraction of the cable attached to the winch.  Also, he can announce immediately the sighting of a ship or any other object he may observe.  The steel cable served as the telephone wire.  The batteries used for the telephone are contained in a portable box, which also houses a combination telephone set for the use of those on board the U-boat in communicating with the pilot.  (2)  Binoculars.  (3)  Clothing.  This is determined by the climate; in a cold climate, the pilot wears a leather suit lined with sheepskin and sheepskin aviator's boots; in the tropics, he wears overalls or dark blue fatigues.  (4)  Shoulder straps and belly girdle.

ASSEMBLY AT START

        In preparing the helicopter for a take-off, at least three men are required in spite of the fact that it weighs only about 132 pounds.  Approximately six to eight minutes are required for assembly,

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depending on the training of the assembling crew.  Fuselage and empennage are taken out of the special compartments and fitted together.  Once the skids are attached to the bottom, the rotor head and the propeller blades are assembled, and the tow-cable is attached.  The winch, with 300 meters of tow cable, is operated by compressed air supplied by the U-boat's compressors.  An auxiliary crank and a brake for use in the operation of the winch are also fitted.  For the take-off, the U-boat is turned into the wind.

THE FLIGHT

        The U-boat travels forward with a speed regulated in accordance with the speed of the wind.  In order to fly the rotor must make from 130 to 250 R.P.M.  The weight of the pilot operating the helicopter influences the suspension; the heavier the pilot, the greater the number of revolutions required for lifting the helicopter into the air off the boat.  Just prior to the moment the U-boat has reached the correct speed in relation to head wind, the joy stick is placed in a forward position.  When the wind speed is correct, the pilot pulls back slowly on the joy stick, which sets the rotor head and propellers at an angle of backward tilt.  As the wind passes through, the propeller revolves and, as the speed increases, the helicopter begins to rise on its cable.  At the same time, the tow-cable is slowly fed out by the winch operator, who is careful to take up the slack at all times.  The pilot must handle the joy stick with great care; he controls the helicopter through "feel", and an experienced pilot can operate it by the noise or

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"sing" of the propeller.  Since the helicopter can weave from side to side about 30 on either side of the U-boat, the pilot can observe the sector astern of the U-boat.  In weaving, the pilot must make each movement slowly, precisely.  A quick jerk or rapid sideward motion may tip the helicopter and cause it to fall into the sea.

LANDING AND DISASSEMBLY

        When the pilot wishes to land, he must push the joy stick forward, thus tilting the rotor head forward and decreasing propeller revolutions.  If this is inadequate, the U-boat must slow down.  At the same time, the slackening tow-cable must be hauled in by the winch.  As the helicopter is hauled in, certain members of the crew stand ready on deck to grasp it as soon as it comes within reach.  This facilitates a safe landing, since movement of the U-boat might otherwise damage the helicopter which itself is bouncing in the air.  The helicopter must be placed firmly on deck.  In most instances, the U-boat is stopped for purposes of landing.  The disassembling and stowage of the helicopter in the water tight compartments can be accomplished by three trained men in about five minutes.  The plane is disassembled in reverse order of assembly, the fuselage being the last member to be placed in the storage compartments.  A trained crew can expedite stowage considerably.

TRAINING OF PILOT

        U-boat helicopter pilots were trained at the glider and helicopter school in Gelnhausen.  The school has a landing field about 600-700 meters long and 300 meters wide.  This field had a hard foundation, but no special drainage system and was without a

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runway.  The weather at Gelnhausen was not considered ideal for gliding.  There was one hangar for gliders.  No camouflage was used at Gelnhausen.

        The school had about fifteen closed fuselage gliders, and three or four open fuselage gliders.  There were three old NSFK glider towing planes.  There were only two of the new U-boat helicopters at the school.

        Personnel at Gelnhausen varied greatly, averaging one hundred school members, and from 50 to 300 students in the glider and helicopter training course.  A survivor of U-177 who attended the course began his work at the school on 1 December 1942, and finished his instruction on 30 May 1943.  At that time there were about 30 trainees in the helicopter course, all from the German Navy.  The naval personnel lived in the same barracks and under the same conditions as the Luftwaffe men who were present for other training, and had no special privileges.  For security reasons, the naval personnel wore no naval insignia.  The survivor's instructor was Feldwebel Wieden of the Luftwaffe, who made the second war cruise on U-177, and reported on the practicality of the helicopter to the Commander-in-Chief U-boats.

        The first part of the instruction consisted of glider training, exactly along the lines followed for training the Luftwaffe.  Students undergoing helicopter training were awarded the same certificates at the completion of the course as those granted to the old students under the administration of the NSFK.  This survivor was given A, B and C certificates and also the

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pilot's license (Fulgfahrerschein).  Students were first given considerable instruction in meteorology and then began actual training with the helicopter.  This training lasted two weeks, during which time students received only two hours of theoretical instruction on the helicopter.

        The survivor stated that the helicopters used at the school were of the same model as that carried by U-177.  The first flight was very simple.  The helicopter rested on a concrete square, and the nose-wire was attached to a winch.  With a light wind blowing, and the propeller blades moving, enough power was generated to lift the helicopter about two meters off the ground.  It hovered there for about two minutes, and then the student brought it down by using the elevators.  About 25 practice ascents were made, and a little more of the winch was played out each time until an altitude of about 100 meters was attained.  During all practice flights the winch was in a fixed position, so that only the force of a light wind, unaided by any forward towing movement, kept the helicopter aloft.

NOTES ON PERFORMANCE

        (a)  Range.  Survivors stated that the helicopter can attain an altitude of approximately 150 meters, permitting visual observation within a radius of about 25 miles, thus augmenting normal lookout range and the use of surface detection devices.

        (b)  Faulty Communications System.  Survivors stated that the telephone cable was short-circuited frequently by soaking with sea water, hampering transmission to the U-boat of orders for operation of the helicopter and sighting reports.

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        (c)  Vulnerability Under Attack.  If the U-boat is obliged to crash-dive under attack by aircraft, helicopter and pilot must be abandoned.

        (d)  Increase in Personnel.  As a high degree of skill is required in the operation of the helicopter specially trained flying personnel must be added to the normal complement of the U-boat.

        (e)  Weather.  Only a narrow range of wind and weather conditions is favorable to U-boat helicopter operations.  Moreover, as the helicopter cannot be operated at night, use is confined to those area in which the U-boat may remain surfaced in daylight with relative safety.

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CHAPTER VI.  CREW OF U-177

        The complement of U-177 at the time of her sinking comprised 65 officers and men, as follows:  7 officers, including a doctor; 20 warrant, chief petty and petty officers; and 38 enlisted men, including 3 seaman-pilots for the helicopter.

OFFICERS

        The Commanding Officer of U-177, Korvettenkapitän Heinz Buchholz, who did not survive, was of the 1929 Naval Term and 35 years old.  An experienced officer, he had entered the U-boat arm in 1934 and commanded U-15 from 1937 until January 1940, when he was relieved for duty with the Operations Division of the Admiralty in Berlin.  In January 1941, he went to the Kommandanten Schule (U-boat Prospective Commanding Officers' School) at Memel as instructor, and later instructed in Norway.  From January 1942 until July 1942 he served as Senior Officer of the First U-boat Flotilla at Brest, leaving to take command of U-195, a new 1200 tonner, in August 1942.  On 10 October 1943 he relieved Korvettenkapitän Gysae as commanding officer of U-177, U-195 having gone into the yard at Bordeaux for conversion and overhaul (See Chapter XIII).  He held the Iron Cross, First Class.

        Buchholz met with obstacles in assuming command of U-177.  A stiff militarist, he brought with him from U-195 a nucleus of officers and men accustomed to his harsh and rigid tenets of conduct; but most of the experienced personnel aboard had served under Gysae, a successful, easy-going and friendly captain, with fervent

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devotion, and did not take easily to the newly prescribed discipline.  Buchholz inflicted punishments for the slightest infractions, where Gysae had been content to maintain morale through intimate and pleasant contact with his men.  The contrast naturally led to friction between the Gysae and Buchholz cliques in the crew, both officers and men.

        Little is known of Buchholz's officers who were lost; all having been reserve officers, their names do not figure in the German Navy List of 1942.  The Executive Officer was Oberleutnant d.R. Heinz Walter, 28.  The Engineer Officer was Leutnant (Ing.) d.R. Arno Seidenberg, 26.  The Second Engineer Officer was Leutnant (Ing.) d.R. Josef Eisele, 23.  The Doctor was Oberassistenzarzt d.R. Peter Becher, 28.

        The 2nd and 3rd Watch Officers survived.  Leutnant z. S. Hans-Otto Brodt, 21 was of the 1940 Naval Term.  As a cadet, he served from December 1940 until February 1941 in the destroyer HERMANN SCHOEMANN, was promoted to midshipman in August 1941 and was sent to Brest for duty with the 2nd Coastal Patrol Flotilla (Minesweepers) in October 1941 for three months.  He was transferred to U-boats early in 1942, was trained in the school bootU-8, under the Command of Oberleutnant z. S. Horst Deckert, and served with the 22nd (training) Flotilla at Gotenhafen as student-instructor in U-145, commanded by Oberleutnant z. S. Reimar Ziesmer, until June 1942.  After further torpedo and communications training, Brodt came to U-195 as midshipman watch-officer in October 1942.  He was aboard U-195 for its only patrol (See Chapter XIII) and transferred

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with Buchholz to U-177 in October 1943, at which time he was commissioned Leutnant.  Brodt idolized Buchholz and was determined to emulate his commanding officer in all respects.  He was said to follow Buchholz about the boat, aping him and issuing orders to the men.  He was held in great contempt by the experienced members of the crew.  To his interrogators, however, he appeared to be without particular affectation or conceit, and conducted himself courteously and pleasantly.  His shortcomings were ascribed to immaturity rather than stupidity.

        The 3rd Watch Officer, who survived, was Leutnant z. S. Christian Schmidt, 20 of the May 1941 Naval Term, and brother of Leutnant z. S. Joachim Schmidt, former Executive Officer of U-203 (O.N.I. Note:  U-203 was sunk on 25 April 1943;  Joachim Schmidt is a prisoner of war).  Schmidt spent 7 months in 1941 as apprentice seaman aboard a Sperrbrecher (mine destructor vessel) in the English Channel, subsequently doing cadet training in M-151 (minesweeper) in the Baltic and the Channel.  He was transferred to the Officer Candidate School at Flensburg in February 1941, was promoted to Fähnrich in May 1942, and came to U-177 at Bremen two days after the air-raid in which Gysae was injured.  He made the first patrol in U-177 as midshipman watch officer, and was put ashore on arrival at Bordeaux in January 1943 to attend various officer schools.  He was promoted to Oberfähnrich in May 1943, continuing his schooling until October 1943 and, after being ordered to a U-boat doing trials in the Baltic, was transferred to Bordeaux, commissioned Leutnant, and recalled by Gysae to U-177 as his 3rd watch officer.

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        Schmidt appeared to have stood in precisely the same relationship to Gysae as Brodt had to Buchholz, that of a favored protege.  His status aboard U-177 was jeopardized, therefore, by Gysae's relinquishment of command.  Schmidt considered Buchholz incompetent and uninspiring and was obliged to give way to Brodt in the role of favorite junior officer.  He was correct and amiable in the presence of interrogating officers; while fairly intelligent, he seemed exceedingly immature.

RATINGS AND ENLISTED MEN

        Many of the more experienced men who had served under Gysae for the long first and second patrols were sent to schools prior to the final patrol and their places taken by comparatively green hands.  U-177 under Buchholz was not the smoothly functioning, efficient machine it had been under Gysae.  It was stated that Gysae, by virtue of his position as a U-boat ace, had been able always to retain his preferred personnel.

        The most experienced man aboard was the Chief Quartermaster, Fabig, who had made some 20 patrols in U-boats and had been awarded the German Cross in gold.  Fabig was a casualty.  Hermann Schütz, the leading machinist, was to receive his commission as an Engineer Officer at the conclusion of the final patrol.  Neither he, nor Müller, a machinist who was stated to have served in U-boats since 1934, survived.  Boatswain's Mate Dittkowski, a survivor, came to U-177 with Buchholz, and had been in the U-boat Arm since 1940.  He held the Iron Cross, First Class.

        Apart from the aforementioned ratings, there were few experienced

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men aboard U-177 at the time of her sinking.

        Among the enlisted men were three seamen, Pitz, Frank and Winter, who had received extensive training ashore as U-boat helicopter pilots (See Chapter V).  Pitz did not survive.

GYSAE AND HIS CREW

        Korvettenkapitän Robert Gysae, of the 1931 Naval Term, served as Commanding Officer of U-177 from March 1942 until October 1943; it was stated that he was relieved in order to assume command of a U-boat Flotilla in the Baltic (O.N.I. Note:  Gysae may command the 26th Flotilla at Danzig).  In 1940, Gysae transferred from destroyers to U-boats, assuming command of U-98 in October 1940 and winning the Knights' Cross of the Iron Cross in January 1942, for the sinking of 12 ships with an aggregate tonnage of 84,000 tons.  His record in U-177 was even more impressive.  In December 1943 the Official German News Agency credited him with the sinking (in both U-98 and U-177) of 27 Allied ships totaling 188,000 tons.  He received the Oak Leaves to the K.C.I.C. and his promotion to Korvettenkapitän at sea on 31 May 1942, following a successful convoy attack (See Chapter IX).  After being relieved of the command of U-177 he was stated to have been awarded the "Swords to the Oak Leaves".

        Gysae was described by survivors as a brilliant, entirely intuitive tactician.  He hated routine, red tape and formality; relied heavily on instinct, and attacked the enemy with a high degree of nervous energy.  It was stated that he emphasized informality not merely in the treatment of his crew but even in navigation and

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torpedo firing.  He squandered torpedoes with magnificent abandon, and conned his ship by "smell", using charts infrequently.  He had never been known to resort to punishment, and spent most of his free time in the mens' quarters rather than in the wardroom.

        When Gysae left U-177, he took all his officers along.  With the exception of the Doctor; they had made both long patrols with him.  The Executive Officer, Oberleutnant Burkhard Heusinger von Waldegg, of the October 1938 Naval Term, left for Prospective Commanding Officer's School.  The distinguished Engineer Officer, Kapitänleutnant (Ing.) Gerhard Bielig, of the 1934 Naval Term, was stated to have been given a teaching post.  (O.N.I. Note:  Bielig is one of the few Engineer Officers to have received the K.C.I.C.   The award was made on 12 February 1943 for his part in the sinking of 51 ships totaling 280,510 tons, for having spent 454 days on patrol and for having saved his U-boat(s) from destruction three times through outstanding ability.)

        The Chief Quartermaster, Mürl, who had acted as 3rd Watch Officer, and was considered by the crew to be the most capable man aboard, also left with Gysae.

MORALE

        Morale aboard U-177, exceptionally high under Gysae because of successes gained and comradeship of officers and men, fell off badly under Buchholz.  The men had little respect for their new officers and resented the change in command.  The officers were not a unified team and were said by an officer survivor to have squabbled continually.

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        Under interrogation, the majority of survivors attempted originally to mislead and confuse the questioning officers.  Low morale and defeatism eventually produced a highly cooperative attitude on most cases.

COMPLEMENT PER PATROL

        U-177 carried 55 officers and men on her first patrol, 61 on her second and 65 on her third patrol.  The increased complement on the second and third patrols were attributable to the addition of the helicopter pilots; the increase in personnel on the third over the second patrol probably resulted in the addition of G.S.R.-Radar specialists.  A medical officer and a pharmacist's mate were carried on each patrol.

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CHAPTER VII.  EARLY HISTORY

COMMISSIONING

        It is not known when U-177 was laid down or when launched.  Of the survivors, one man came to the U-boat at the Deschimag Yards, Bremen in February 1942.  U-177 had been launched and was being fitted out.  The commissioning took place on 1 March 1942.  Although U-177 was to be Gysae's boat, he did not commission her, as he had not yet been relieved of his former command (O.N.I. Note:  Gysae is known to have commanded U-98 prior to U-177).  Instead, she was commissioned formally by a Kapitänleutnant Schulze, Gysae assuming command one week later.  (O.N.I. Note:  This was probably Kapitänleutnant Herbert Schultze, who is believed to have been serving at that time as special U-boat consultant to Admiral von Friedeburg in Kiel).  The commissioning celebration was modest, consisting of a beer party on deck following the ceremony and an informal gathering at the Lloydheim in the evening.  The Directors of Deschimag presented U-177 with electric hair clippers and each man with a pocket knife.