Capital Ships of the Imperial Japanese Navy, 1868–1945: The Yamato Class and Subsequent Planning

345 Pages·2014·22.17 MB·English

by  Hans Lengerer

Table of Contents
Preface
Acknowledgements from Hans Lengerer
Acknowledgements from Lars Ahlberg
(Untitled)
Introduction
Chapter 1–Design History and General Description
Summary
Requirements and Design
Construction
Individuals Involved in Yamato’s Construction
Building Expenses and Man-Days
General Arrangement
Protection
Damage Control and Stability
74F
Machinery 68
Funnel
Shafts, Rudders, Steering Gear and some Noteworthy Auxiliaries
Turning Ability
Chapter 2–Outline Description of the Main Armament
Decision of the Main Gun Calibre: 45.7-cm or 50.8-cm?
Armor-Piercing Projectile and Ballistic Properties
Main Gun Turrets
Countermeasures Against Blast
Increase of Anti-Aircraft Weapons
Chapter 3–Fire Control System
The Type 98 Fire Control System
The Type 98 Fire Director
The Type 98 Target Speed and Bearing Panel (Sokutekiban)
The 15-m Triple Type Rangefinder (Sanjū Sokkyogi)
The Type 98 Model 1 Computer (Shagekiban) and the Range-Averaging
Panel (Sokkyo Heikinban)
Notes
C S I J N
APITAL HIPS OF THE MPERIAL APANESE AVY 1868–1945
I B B C
RONCLADS, ATTLESHIPS & ATTLE RUISERS:
A O H T D
N UTLINE ISTORY OF HEIR ESIGN,
V III
OLUME

T Y C
HE AMATO LASS
W
ITH 87 PHOTOS, 202 FIGURES/DRAWINGS, 15 MAPS/TRACK

CHARTS, 60 TABLES

H L L A
ANS ENGERER & ARS HLBERG
N
B LLC
IMBLE OOKS
Nimble Books LLC
1521 Martha Avenue
Ann Arbor, MI, USA 48103
http://www.NimbleBooks.com
[email protected]
+1.734-646-6277

Copyright 2014 Hans Lengerer and Lars Ahlberg
Printed in the United States of America
ISBN-13: 978-1-60888-083-6

♾ The paper used in print versions of this publication meets the
minimum requirements of the American National Standard for
Information Sciences—Permanence of Paper for Printed Library
Materials, ANSI Z39.48-1992. The paper is acid-free and lignin-free.
T C
ABLE OF ONTENTS
Introduction 1
Part I: Technical Section17
Chapter 1—Design History and General Description19
Chapter 2–Outline Description of the Main
Armament 147
Chapter 3–Fire Control System 195
Chapter 4–Bridge Structure 233
Chapter 5–Additional Notes on the Armor Protection 267
Chapter 6–Detailed Description of the Main Gun Turret
Part II: Operational Section369
Chapter 7—Operational Histories371
Chapter 8—Loss of the Musashi415
Chapter 1—Loss of the Yamato457
Part III: Subsequent Planning Section527
Chapter 10—Incomplete Sisters and the Never-Built
Super Yamato Class529
Select Bibliography543
P
REFACE
This is the third volume of a trilogy dealing with the history of the
Japanese capital ships (armorclads, battleships and battle cruisers) from
the introduction of the first armorclad in the early Meiji era until the
definite end of the battleship era, coinciding with the end of World War
II.
Volume One will deal with the foreign built armorclads and
battleships from Fusō (I) to Kongō (II), in company with the Chinese
(1895) and Russian war prizes (1905), incorporated in the register of
Imperial Japanese Navy (IJN) warships as either second class or first
class battleships, and the first domestic built forerunners of the battle
cruiser and pre- and semi-dreadnoughts, the latter built in a period
dominated by the British Dreadnought and hence already outdated when
commissioned. Irrespective of this fate, design and construction of these
ships, less than forty years after the Meiji Restoration, was a milestone
in the history of Japanese warship construction and proof of the breath-
taking tempo of Japan’s struggle to become a world naval power. The
building of two sisters of the battle cruisers of the Kongō class in
civilian shipyards meant the preliminary completion of the military-
industrial complex. During this period of time the foremost imaginary
enemy, against which the naval armament was directed, changed from
Russia to China in 1882 and back again to Russia in 1895 before, in
1907, the United States was included in the list of imaginary enemies,
but considered a budgetary enemy rather than an actual one.
Volume Two will be dedicated to the super-dreadnought type battleships designed and
built within the scope of Japan’s famous Eight-Eight Fleet (in 1918 expanded to the Eight-
Eight-Eight Fleet). Both plans came to an abrupt end with the Washington Arms
Limitation Treaty in 1922. Even though the conclusion unburdened the national budget
and permitted the reduction of the naval organisation, including the military-industrial
complex, the ratio, decided by the treaty on the basis of the existing capital ship tonnage,
caused consternation. Forced to revise the strategic and tactical planning against the
primary hypothetical enemy (which had been the United States since 1918), the Naval
General Staff conceived countermeasures, which strongly influenced shipbuilding policy
and affected the modernization of the capital ships, particularly those built before the
lessons of the Jutland sea battle in 1916 were known and applied to newly built ships. The
London Arms Limitation Treaty in 1930 imposed further restrictions upon the IJN. These
referred primarily to ship types not considered in the former treaty and also caused the
conversion of the battleship Hiei into a training ship. These changes reinforced the effects
already exerted by the first treaty and the military order made efforts to invent
unconventional countermeasures and upgrade the fighting power of the existing capital
ships on the basis of a revised operational planning.

A H
CKNOWLEDGEMENTS FROM ANS
L
ENGERER
In compiling the material for this monograph I depended heavily upon the extraordinary
kind assistance and generous support of many individuals, besides those to whose memory
this book is dedicated. The help of these individuals and others mentioned later was not, of
course, limited to the Yamato class, and, as a matter of fact, some of them never supplied
information about these giants. Instead they shared parts of their special interests in the
Meiji and Taishō eras war vessels and their immense knowledge of Japanese naval history
in general with me. For instance, Professor Takahashi Shigeo, who spoke and wrote
German, was instrumental in writing a manuscript on the Meiji navy, former Rear-Admiral
Takasu Kōichi, who studied weapon technology at the Tōkyō University in 1943,
promoted my understanding in this particular field and Dr. Itani Jirō, a naval chemist,
provided documents, literature, and insightful advice. In doing so they provided invaluable
help and one part of the fruits of their efforts will be expressed in volumes I and II of this
trilogy. It is for this reason that this volume also is dedicated to them. Among Japanese
individuals I am especially thankful to (in alphabetical order) Messrs. Endō Akira, Fujita
Takashi, Hayashi Yoshikazu, Kamakura Takumi, Kimata Jirō, Kitagawa Ken’ichi,
Kitamura Kunio, Koike Naohiko, Maejima Hajime, Mizutani Kiyotaka, Dr. Morino
Tetsuo, Naitō Hatsuho (via Dr. Itani) and Tamura Toshio.
Special thanks go to Messrs. Izumi Kōzō and Tsukamoto Hideki. It was by the good
offices of Mr. Tsukamoto that Mr. Izumi permitted the use of some of his very fine
drawings. Mr. Tsukamoto has already been introduced in the book BC Kongō Class–CV
1
Unryū Class and Mr. Izumi, one of Japan’s leading model builders, if not the leading
0F
model builder, requires no introduction to scholars of Japanese naval history. Model
builders and readers will surely enjoy the reproduction of more of his drawings in volumes
I and II.
The generous use of photographs from the well-known Fukui Shizuo Collection, which
is now in the possession of the Kure Maritime Museum, was permitted by Messrs. Todaka
Kazushige, the director of the Yamato Museum, and Tsuda Fumio, the head of the Curator
Service of the Museum, for which I would like to express my utmost thanks once again.
Photos from this outstanding collection have been published, in the previously mentioned
2
book about the Kongō and Unryū classes as well as in Japanese Hybrid Warships.
1F
The descriptions of the last operations of Yamato and Musashi, ending
with their total loss, depend very much upon the Japanese official war
history, compiled in 102 volumes. Written permission for the use of
selected volumes including track charts, maps, cruising dispositions and
other illustrations was obtained, besides others, by the good offices of
Dr. Itani, who visited what was then called the Historical Branch at the
end of the 1980s. Copies of track charts etc. as drawn in the detailed
action reports (DARs) or redrawn on their basis are reprinted for their
value as documentary material.
Even with such support I am sure that owing to my amateurish
knowledge and understanding, errors of fact or interpretation will be
discovered and I wish to point out that I alone am responsible for such
errors in the Introduction and chapters 1–6 and 8–10.

Hans Lengerer
Birkenhard, Germany
14 June 2014
A L
CKNOWLEDGEMENTS FROM ARS
A
HLBERG
Over the years several individuals have supplied me with information
about the Imperial Japanese Navy.
I would particularly like to mention Messrs. Ishibashi Takao, an excellent draughtsman
and a noted authority on the IJN (his recent book Senkan • Jun-yōsenkan is highly
3
recommended ), who has not only answered my questions but also gave me permission
2F
to use some drawings; Nakagawa Tsutomu, author of numerous articles for the well-
known journal Sekai no Kansen; Takagi Hiroshi, an expert on propulsion systems who
also gained me permission to use drawings from Sekai no Kansen and Maru (Ushioshobō-
Kōjinsha Co., Ltd.); the late Rear-Admiral Takasu Kōichi, who has already been
introduced above; and Iwasaki Yutaka, a naval architect who has also checked and re-
checked many Japanese expressions.
For the operational section of this book Messrs. Robert Hackett and Sander Kingsepp
have kindly permitted me to use the Tabular Records of Movement (TROMs) as published
4
on the Internet site Senkan! Stories and Battle Histories of the IJN’s Battleships .
3F
Mr. Nathan Okun, a leading authority on guns and armor, has read
parts of an early draft of the armor and armament sections and his expert
knowledge is greatly appreciated. Several remarks made by him are
included in the presented text. Mr. Richard Worth, an excellent naval
historian and author, has generously answered numerous questions.
Without the assistance of all these individuals it would have been
much more difficult to write this story about the Yamato class battleships
and any merit this work possesses is in large part attributable to their
generosity. I therefore express my warmest thanks to them all. Any
errors and omissions are, however, my own responsibility.

Lars Ahlberg
Halmstad, Sweden
14 June 2014