Torpedo Data Computer Mark 3

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Folks,

Torpedo Data Computer Mark 3, Mark 3, Mods 5 to 12 inclusive, O.P. 1056, 1944 describes the most successful torpedo fire control computer of WW II. It is considered a masterpiece of mechanical computing design.

This online version of the manual is provided in PDF format. This means that the files are large and you consider saving them to your local hard disk for repeated viewings to avoid long downloads.

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Richard Pekelney
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Ordnance Pamphlet 1056
Torpedo Data Computer, Mark 3, Mods 5 to 12 Inclusive
A Bureau of Ordnance Publication - June 1944

TABLE OF CONTENTS

SECTION 1-Analysis of the Fire Control Problem	11 (3.5 MB PDF)
Terminology and Symbols	13
Distances	13
Speeds	15
Time	15
Angles	15
Review of Trigonometry	18
Derivation of Equations	21
General Problem	21
Derivation of Equations Solved by the Position Keeper	22
Derivation of Equations Solved by the Sound Bearing Converter	27
Derivation of Equations Solved by the Angle Solver	29

SECTION 2-Fundamentals of Components of the Data Computer	33 (2.5 MB PDF)
Differentials	34
Integrator	42
Resolvers	44
Proportionator	48
Follow-up Head	50
Cams	52
Dials	54

SECTION 3-Function	55 (8.9 MB PDF)
General Function of the Computer	56
Mechanical Follow-up Heads	58
Integrator Unit	66
Divider Unit	67
Position Keeper	68
Functional Diagram of Position Keeper and Sound Bearing Converter	68A
Functional Description of Position Keeper	69
Gear Diagram of Position Keeper and Sound Bearing Converter	75A
The Sound Bearing Converter	76
Unit Assembly Diagram of Position Keeper and Sound Bearing Converter	78A
Resolver Unit	79
Proportionator Unit	80
Differential Unit	81
Cam Unit	82
Base Line Resolver	84
Angle Solvers	85
Functional Diagram of the fwd Angle Solver	86A
Functional Description of the Angle Solver	87
Gear Diagram of the fwd Angle Solver	93A
Unit Assembly Diagram of the fwd Angle Solver	95A
Internal Wiring Diagram of Angle Solver and Position Keeper	97A

SECTION 4-Construction	99 (6.1 MB PDF)
General	100
Position Keeper Section	104
Exterior	104
Interior	105
Dials	107
Angle Solver Section	108
Exterior	108
Interior	109
Dials	111
Interconnection of the Cases	113
Resolver Unit	114
Proportionator Unit	120
Differential Unit	124
Detent Mechanism	126
Divider Unit	127
Time Motor Governor	128
Integrator Unit	129
Sound Bearing Converter	132
Cam Unit	136
Stops	142
Follow-up Heads	143

SECTION 5-Disassembly and Reassembly	145 (9.4 MB PDF)
Separation and Removal of Chassis	146
Removal of Position Keeper From Case	152
Removal of Angle Solver From Case	154
Disassembly of Position Keeper Chassis	157
Disassembly of Angle Solver Chassis	163
Reassembly of Position Keeper	170
Reassembly of the Angle Solver	186
Securing the Sections in Place	204

SECTION 6-Tests	217 (2.8 MB PDF)
Position Keeper Tests	218
For Mk. 3, Mods. 5 to 12, Inc.	220
For Mk. 3, Mods. 5-9, 11 and 12, only	222
For Mk. 3, Mods. 5-9 and 12, only	222
For Mk. 3, Mod. 10, only	224
For Mk. 3, Mods. 10 and 11, only	224
Position Keeper Notes	224
Angle Solver Tests	224
For Mk. 3, Mods. 5 to 12, Inc.	226
Angle Solver Notes	232
Sound Bearing Converter Tests	233
Sound Bearing Converter Note	233

SECTION 7-Installation	235 (1.5 MB PDF)

SECTION 8-Adjustments	247 (1.7 MB PDF)
Thermostat	248
Time Motor Governor	248
Slip Clutches	248
Follow-up Motor Damps	248
Angle Solver Range Stop Switches	250
Offset Angle Zero Detent Switches	250
Integrator Unit and Divider Unit Discs	250
Synchro Motor and Generator Electrical Zero	250
Mechanical Follow-up Heads	250
Correct Solution Light Switches	252
Dials	254
Sound Base Line	254
Tube Base Line	254
Cam Unit Settings	256
Replacing Uy and M Knob Dials	256
Replacing Angle Solver Front Cover	256

SECTION 9-Lubrication	259 (.5 MB PDF)
Synchro Bearings	260
Follow-up Heads	260
Integrator Discs and Time Motor	261
Miscellaneous	262

SECTION 10-Appendix	263 (1.8 MB PDF)
General Information	264
Inputs and Outputs	265
Dial and Counter Graduations	267
Relative Speeds	271
Principal Drawings	271
Element Numbers	272
Exercising Stored Instruments	276
Distribution List	277