Prüf-Nr.

Secret!

Torpedo-Schießvorschrift

für U-Boote

(T.S.V.U.)

Booklet 3

Conducting torpedo fire on U-Boats

Berlin 1943

Introductory remarks.............................................................…......... 5

Initial settings of the system …......................................................... 6

I. The procedure of usage of the fully operational the

A. The salvo shot and multiple shot

calculator and periscope or night sight….......................... 9

subsystem nonoperational — ….......................…............ 15

B. The salvo shot with the torpedo calculator and periscope

or night sight — the target bearing transmission

subsystem and gyro angle transmission subsystem

nonoperational — …....................................................... 17

III. Remarks regarding to particular orders and procedures

A. With fully operational torpedo fire control system (I A) .. 21

B. Without usage of the torpedo fire control system (I B) .... 26

C. With partially damaged torpedo fire control system

(II A i B) …........................................................................ 29

'' 3: The location of the torpedo fire control system elements

on the type IX U-Boats

'' 4: The location of the torpedo fire control system elements

on the type X U-Boats

5

Introductory remarks

The torpedo fire control system when used together with regular way of

passing orders is reliable tool, which makes possible accurate torpedo shooting

in any tactical situation..

Its advantages:

1. eliminating the necessity of manual calculations,

2. easiness in taking into account and introducing different locations of the

3. taking into account the parallax correction and length of the target

2. the operators, who can make mistake.

The elimination of these disadvantages is up to the commander and is

possible by proper servicing and regular operational tests of the torpedo fire

control system and strict following the procedure of the issuing and

acknowledging the orders.

The procedure of the passing orders is so constructed, that appropriate

acknowledging eliminates the misunderstanding of the order.

The sequence of the orders and acknowledgments should be systematically

practiced and should not be changed.

hectometers, knots and so on). The values used in the examples were chosen

arbitrarily.

The way of the passing orders (intercom or voice pipes) is irrelevant.

In this regulations the particular crew members are not assigned to the

6

The chapter II contains procedure used when the torpedo fire control system

is partially damaged.

The chapter III contains remarks related to the particular procedures used

when shooting torpedoes with fully operational torpedo fire control system,

without usage of this system and with partially damaged torpedo fire control

system. In chapter III D are discussed capabilities of the salvo shot.

Although the torpedo fire control systems differs in the number of torpedo

tubes (bow and stern) as well as in the location of the particular elements of the

system, these regulations are so constructed, that are valid for all variants of the

system.

familiarize himself with specific situations described in the examples.

The tables included in the appendix present the location of the particular

elements of the system on the particular types of the U-Boats and the flow of

the ω, ρ, ψ i Δφ

e

data.

Initial settings of the system

Initial settings should be applied each time before starting the torpedo fire

control system up.

While shooting without usage of the system (the deflection angle is set at

the periscope), the deflection angle can be calculated by means of the torpedo

7

the gyro setting gears (GA-Stellzeug) of the torpedoes.

The gyro setting gears are disengaged and they are engaged only while

preparing for attack (see the remarks in the Torpedo-Schußtafel).

All pointers are set into the initial position, »0°« or »180°«. Each time the

torpedo is serviced, it should be checked if the gyro in the torpedo is set to the

value »0« and if the gyro angle receiver is also set to »0°« or »180°«.

Uncoupling the gyro setting gears of the torpedoes from the gyro angle

receiver is allowed only in case of damage of the receiver or coupling shafts.

The target follow-up switch (Blauschalter): Initially the target follow-up

switch is off, that means the servo of the component for calculating the current

automatisch) (The high speed switch (Schnellgang) is used only when

absolutely necessary).

The gyro angle receiver receives the gyro angle from the calculator (the

follow-up lamp is used only as control lamp). In case of electrical power

Initial settings of the torpedo calculator:

angle on the bow: 0, target length: 150 m,

distance in range from 1100 to 1300 m.

calculating the »current angle on the bow« (»Lage laufend«).

The target follow-up switch is in position »Blue (Do not follow-up)«

8

20

III A 21

5. The target follow-up switch (Blauschalter) is set in position

»Blue (Do not follow-up)« (»Blau (Nicht folgen)«). It is left to

the commanders to decide, when the orders »Follow-up the

target« (»Folgen«) and »current angle on the bow« (»Lage

laufend«) are issued for the first time.

One has to be sure, that just before launching the torpedoes,

the »Follow-up the target« (»Folgen«) and »Current angle on the

bow« (»Lage laufend«) orders were issued, whereby the mistakes

resulting from forgetting the operation of the follow-up switch

can be avoided and the gyro angle setting gears will not be

The fire control system: the activation of the fire control

system is indicated by illumination of the torpedo calculator dials

and noise of the running calculator's servo-motors.

The switches at the control boxes can be set in any position (they

do not have the »Off« (»Aus«) position).

During the daily checks of the fire control system there

should be performed the test of the synchronization of the

particular elements of the system

9

»System is fully operational« (»klar«).

shot! (Rohr I bis IV klarmachen zum Unter- bzw.

Überwasserschuß!)

This order should be issued as early as possible.

1. The ordered tubes are flooded.

2. The muzzle doors of the flooded tubes are opened.

The flooding of the tubes and opening of the muzzle doors is

reported to the control room before performing these action, so

the L.I. can take respective measures to maintain the trim of the

U-Boat

10

.

4. The direction valve has to be set in the position »Submerged or

surfaced launch«

Ad No. 3: 4-torpedo salvo shot with torpedo calculator! Select the

attack periscope! (Viererfächer mit Vorhaltrechner! Schaltung

of the aiming subsystem sets

»target bearing transmitter select« (»Zielrichtung«) switch

into position »attack periscope« (»Standsehrohr«),

»gyro angle receiver select« (»Schußrichtung«) switch into

»the switch for selecting the active firing lever« (»T-Abf.-

Schalter«) in position »Conning tower« (»Turm«).

3. The torpedo calculator operator sets the parallax switch to »bow

tubes« (»Vordere Rohre«).

4. The gyro angle receiver operator sets the salvo size select switch

into position »4-torpedo salvo« (»4er-Fächer«) and switches

the servo-motor on.

Ad No. 3a: Multiple shot from tubes I, II, III i IV with torpedo

calculator! And so on. (Verbundene Einzelschüsse aus Rohr I, II,

III, IV mit Vorhaltrechner! usw.)

for single shot!« (»Streuwinkel für Einzelschuß geschaltet!«),

because it means, that salvo spread angle was set to »0« at the gyro

angle receiver.

While shooting multiple salvos

13

Ad No. 4: Torpedo depth 4! Torpedo speed 30! And so on. (Tiefe 4,

Torpedogeschwindigkeit 30! usw.)

fire.

2. The torpedo calculator operator repeats and introduces ordered

values. Each value is acknowledged with the report »Set«

(»Steht«).

The values for calculator should be ordered in the same,

unchanged sequence. Moreover, it is recommended to predict the

spread angle pointer with the value received from torpedo

calculator or value passed verbally.

Ad No. 5: Follow-up the target! (Folgen!)

This order should not be issued to soon. Blue light in the conning

tower is off. After ordering »Follow-up the target!« (»Folgen!«) the

periscope has to be aimed at the target. Before lowering the

periscope, the order »Do not follow-up!« (»Blau!«) should be given.

The torpedo calculator operator monitors, if the target bearing is

changing according to the periscope bearing change and reports the

current bearing. The shooter compares the reported bearing with the

The faithful operation of the follow-up switch is essential. The

careless operation of this switch can introduce the errors into the fire

control system and result in the attack failure.

angle on the bow!« (»Lage laufend!«) can be also issued before

introducing all other values, to register and verify the convenient

angle on the bow of the target

15

introduce the angle on the bow and then ordering »Follow-up the

target!« (»Folgen!«) and »Current angle on the bow!« (»Lage

laufend!«). The aiming device has to be placed at the target until the

calculator operator reports »Set!« (»Steht!«).

To make sure that torpedo calculator transmits the solution to the

gyro angle receiver correctly, it is recommended to check the

reports the results.

After comparing the calculated current angle on the bow with the

target silhouette, the angle on the bow adjustments are made if

necessary.

movement of the aiming device does not result in the change of the

calculated angle on the bow to the opposite.

Ad No. 7: Get ready to the salvo shot! Turning speed correction 2

starboard! (Fächer fertig! Grün 2!)

1. Pull out the safety cotters of the firing gears at the torpedo tubes.

2. Unlock the hand firing levers at the torpedo tubes in the bow

torpedo room.

3. Unlock the firing lever in the conning tower.

4. Introduce into the calculator the turning speed correction. The

turning speed correction is introduced each time when the U-Boat

continuously: No alignment! (Keine Deckung!)

Ad No. 7a: Get ready to the shot from the tubes from I to IV! Turning

speed correction 2 starboard! (Rohr I bis IV fertig! Grün 2!)

To avoid the delay between the subsequent launches, all tubes are

getting ready simultaneously. The other notes as in paragraph No. 7,

Ad No. 8: Salvo ........... fire! (Fächer ........... los!)

Between the words »Salvo« (»Fächer«) and »fire« (»los«) there

should be a pause about 8 seconds, so L.I. can take respective

necessary to report to the commander, that torpedo failed to

launch (together with the tube number).

3. Before launching the last torpedo in salvo or in the moment of

launching the last torpedo of multiple single shot, the torpedo

calculator operator - without waiting for the order - sets the

follow-up switch into position »Blue (Do not follow-up)« (»Blau

(Nicht folgen)« ) and switches the motor of the component for

calculating the current angle on the bow off. These actions make

possible writing down from the calculator dials the values used

for attack.

3. Set the direction valves at the tubes to the position »Surfaced

launch« (»Schuß bei Überwasserfahrt«).

4. Secure the firing lever in the conning tower.

Ad No. 8a: Tube I ............ fire! (Rohr I ............ los!)

The notes similar as in the paragraph No. 8. It is not necessary to

make 8 second pause. The torpedoes should be launched as fast as

possible. After each launch one has to wait for the report »Torpedo

gyro aligned with the gyro angle« (»Deckung«).

Ad No. 9: Leave the battle stations! (Wegtreten von Gefechtsstation!)

After this order, the torpedo firing, torpedo fire control and

Ad No. 1: Battle stations! (Auf Gefechtsstation!)

This is general order, which applies to all stations of the U-Boat.

1. The bow and stern torpedo tubes are manned.

2. All gyro angle setting gears are engaged in the zero-setting.

3. The torpedo firing, torpedo fire control and internal

communication systems are switched on and checked.

Ad No. 2: Ready the tubes from I to IV for submerged shot

reported to the control room before performing these action, so

the L.I. can take respective measures to maintain the trim of the

U-Boat.

3. The air flasks are charged with compressed air. After charging,

the pressure is monitored and maintained by Torpedo Matt. He

in the air flasks can result in jamming of the torpedo in the tube

(so called Rohrläufers).

4. The direction valve has to be set in the position »Submerged

launch« (»Schuß bei Unterwasserfahrt«).

into position »Off« (»Aus«),

»gyro angle receiver select« (»Schußrichtung«) switch into

position »Bow torpedo room« (»Bug-Torpedoraum«).

2. At the control boxes of the firing subsystem:

»the switch for selecting the torpedo tube(s)« (»Einzelschuß«) in

position »Salvo« (»Fächer«),

»the switch for selecting salvo configuration« (»Fächerschuß«)

»the switch for selecting the active firing lever« (»T-Abf.-

Schalter«) in position »Conning tower« (»Turm«).

3. The gyro angle receiver operator sets the salvo size select switch

3. The attention should be paid, to keep the parallax pointers

matched together. If the servo-motor of the component for

calculating the parallax correction is operational, it can be