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Kyushu Airplane Company
(Kyushu Hikoki K K) —p. ry (p C I
CORPORATION REPORT NO. XV
(Airframes)
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Aircraft Division
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7X
February 1947
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MILITARY STUDIES Military Analysis Division
61 Air Forces Allied with the United States in the War
Against Japan
62 Japanese Air Power
RQ Tonaiieie Air Weapons and l actios
tl Th'f Effect ofAir Action on Japanese Ground Army
65 Empfovment of Forces Under the Southwe^ Pacific
- ^2Efin^h^fSi^:^^(^s
67 Air'op^e?ItiL in China, Burma. India-World War
68 Th" Air Transport Command in the War Against
rq The'^'-inlirteenth Air Force in the War Against Japan 70 The Seventh and Eleventh Air Forces ui the \A ar
7, Tt^'piful i^r Force in (he War Agai,>st Japan
*72
*73
*74
*75
76
*77 78 79
80 81 82 83 84 85 8fi
Naval Analysis Division
The Interrogations of Japanese Officials )Vols. T and
Campaigns of the Pacific War The Reduction of Wake Island The Allied Campaign Against Ral.aul The American Campaign Against \\ ot e, Maloclap, MiUe, and Jaluit (Vols. I, II and III)
Vu- KstrMhilLaving Campaign Against Japan Reporfof Ships Bombardment Survey Party-Fo e word, Introduction, Conclusions, and General
RepoToT^Ships Bombardment Survey Party (En-
closure A). Kaniaishi Area Report of Ships Bombardment Survey Party (En- closure B), Hamamatsu Area Report of Ships Bombardment Survey Party (En- closure C), Hitachi Area „ Report of Ships Bombardment Survey Party (En- closure D), Hakodate Area Re^^rt of Ships Bombardment Survey Party (En-
closure E), Muroran Area „
RepOTt of Siiips Bombardment Survey Party (En-
closure F). Shimizu Area ,-,-,
Re. oH of Ships Bombardment Survey Party (En- closures (i and H), Shionomi-Saki and Nojima- Saki Areas
S7 Renort of Ships Bombardment Survey Party (I ^ ^"ctosure I), Comments and Data on EfTectiven
of Ammunition SS ReiJort of Ships Bombardment Survey Party (1
closure J), Comments and Data on Accuracy
Firing ^ -n ^ n
m Renorts of Ships Bombardment Survey Party (1
closure K), Effects of Surface Bombardments
Japanese War Potential
Physical Damage Control
.)0 Effect of the Incendiary Bomb .Mtacks op Japan
Reiiort on Eight Cities) 01 The Effects of the Ten Thousand Pound Bomb • Japanese Targets (a Report, on N me Incidents)
.)2 Effects of the Atomic Bomb on Hiroshima, Japai i.3 Effects of the Atomic Bomb on Nagasaki, Japan ■j-l Effects of the Four Thousand Pound Bomb on Ja
nese Targets (a Report on Pive Incidents)
.,r, Effects of Two Thousand, One Thousand and 1 Hundred Pound Bombs on Japanese Target. Report on l^ight Incidents)
90 A Report on Physical Damage in Japan (Sumni Report)
97
98
99
100
101
102
103
104
105
*106
*107
108
G 2 Division
Tananese Military and Naval Intelligence ivaluatton of Photographic Intelligence in the J.
neslHomeland, Part I, Comprehensive Repor, Evaluation of Photographic Inl^l 'gence in the .h
iiese Homeland, Part II, Airfields
Evaluation of Photographic^ ntelhgence in the J,
nese Homeland, Part V, C«wo».^age Evaluation of Photographic Intelligence in the J.
nese Homeland, Part \I, Shipping Evaluation of Photographic Intelligence in the J
nese Homeland, Part VII, Electronics _ Evaluation of Photographic Intelligence in the J nese Homeland, Part VIII, Beachlntelbgence Evaluation of Photographic Inte hgence m the J
nese Homeland, Part IX, Artillery Evaluation of Photographic Intelligence in the J ne^ Homeland, Part X, Roads and Radroads Evaluation of Photographic Intelligence in he J nee Homeland, pirt XI, Industrial Analysis
■ I
68
U. S. GOVERNMENT PRINTING OFFICE; 19<?
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THE UNITED STATES STRATEGIC BOMBING SURVEY
Underground Production
OF
Japanese Aircraft
REPORT NO. XX
Aircraft Division March 1947
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THE UNITED STATES STRATEGIC BOMBING SURVEY
Underground Production
OF
Japanese Aircraft
REPORT NO. XX
Aircraft Division
Dates of Survey:
2 3 October-25 November 1945
Date of Publication:
March 1947
M(a3
A
0. S. SUHtKlWIENUtNf Of UUUUMtNCt
JUL 19 1947
This report was Avritteii priinavily for the use of the United States Strategic Bombing Survey in the prepaiation of further reports of a more comprehen- sive nature. Any conclusions or opinions expressed in this report must be considered as limited to the specific material covered and as subject to further interpretation in tlie light of furllier studies conducted by the Survey.
II
FOREWORD
The United States Strategic Bombing Survey ;as established by the Secretary of War ou 3 lovember 1044, pursuant to a directive from the ite President Koosevelt. Its mission was to con- uct an impartial and expert study of the effects f our aerial attack on Germany, to be used in ounection with air attacks on Japan and to stahlish a basis for evaluating the importance nd potentialities of air power as an instrument f military strategy for planning the future de- elopment of the United States armed forces and or determining future economic policies with espect to the national defense. A summary re- lovt and some 200 supporting reports containing lie findings of the Survey in Germany have been ublished.
On 15 August 1945, President Truman requested hat the Survey conduct a similar study of the ffects of all types of air attack in the war against 'apan, submitting reports in duplicate to the Secretary of War and to the Secretary of the Javy. The officers of the Survey during its apanese phase were:
Franklin D'Olier, Chairman.
Paul H. Nitze, Henry C. Alexander, Vice
Chairmen. Harry L. Bowman, J. Kenneth Galbraith, Eensis Likert, Frank A. McNamee, Jr., Fred Searls, Jr., Monroe E. Spaght, Dr. Lewis R. Thompson, Theodore P. Wright, Direrfom. Walter Wilds, Secretary.
The Survey's complement provided for ;JOU civilians, 350 officers, and 500 enlisted men. The military segment of the organization was drawn from the Army to the extent of 00 percent, and from the Navy to the extent of 40 percent. Botli the Army and the Navy gave the Survey all possi- ble assistance in furnishing men, supplies, trans- port, and information. The Survey operated from headquarters established in Tokyo early in September 1945, with subheadquarters in Nagoya, Osaka, Hiroshima, and Nagasaki, and with mobile teams operating in other parts of Japan, the islands of the I'acilic, and the Asiatic mainland.
It was possible to reconstruct much of wartime Japanese military planning and execution, en- gagement by engagement, and campaign by cam- paign, and to secure reasonably accurate statistics on Japan's economy and war production, plant by plant, and industry by industry. In addition, studies were conducted on Japan's over -all stra- tegic plans and the background of her entry into the war, the internal discussions and negotiations leading to her acceptance of unconditional sur- render, the course of healtli and morale among the civilian jjopulatiou, the effectiveness of tiie Japa- nese civilian defense organization, and the effects of the atomic bombs. Separate reports will be issued covering each phase of the study.
The Survey interrogated more than 700 Japa- nese military, government, and industrial officials. It also recovered and translated many documents Avhicli not only have been useful to the Survey, but also will furnish data valuable for other studies. Arrangements have been made to turn over the Survey's files to the Central Intelligence Group, through which they will be available for further examination and distribution.
Ill
TABLE OF CONTENTS
Page
Inlroductioii 1
Paut I UndergioniKl Pl.iiils of Xak;ijim;i Aiicraft Company 2
Part 1 1 l^iulei-yidiiiid J'laiits of JMitsubislii Aiici-aft Company 33
Part 111 Minor Aiiciaft Companies 53
IV
INTRODUCTION
Because the disspeisal ol' airi rail and engine manufactuiiiig' plants to uu- (lei-gi'onnil locations proved to he fai- nioi-e extensive tlian had been suspected, a special sttidy of undergiouml phints was undertaken by the Aircraft Divi- sion. Lt. Col. J. W. Fredricks was assigned to the task. He made extensive preliminary investigations of Munitions Jlinisfry, Army and Navy, and in- dustrial records, followed up by tiehl in\estigations at many underground sites throughout Japan. A summary of his findings ajiiiears in Section II of the Aircraft Division's rejioit on "The .laijauese Aircraft Industry". The fol- low pages comprise a series of "thumb nail" reports on several sites which he visited.
714387—47—2
PART I
UNDERGROUND PLANTS OF NAKAJIMA AIRCRAFT CO,
OYA
AVlien Allied ;iir attacks toward the end of 1944 made it evident to the Nakajima Aircraft Co. that their plants were vulnerable, plans were drawn to disperse them and, insofar as possible, place them underground. Oya and Shiroyama in TawancliiGun, Tochigi prefecture, four miles northwest of Utsunomiya were selected for the dispersal of part of the airplane engine manufac turing facilities of the Nusashi plant near Tokyo, and later for the dispersal of most of the air- frame manufacturing and assembling facilities at Utsunomiya. This works, both engine and air- frame, was the best developed and most extensive of all the Japanese underground plants.
The area was selected largely because many of the surrounding hills were already honeycombed
with stone quarries that provided large unde ground areas already dug. The stone was rel tively soft and would therefore readily lend itse to changes or expansion of the existing caves. Plans called for the utilization of two separa underground areas and three surface areas f the manufacture of one engine type, the Japane Army designated Ha 45, Model 12 (1795 hp This engine was the type used in the Prank Am fighter (Japanese Ki 84) which was being assa bled at nearby rtsnnoiniya, and later was to assembled in other underground works in t Oya area. The following table gives details the engine works, and compares plan Avith acco: plishment :
|
Location |
Utilization |
Area in square feet |
Equipment' ■ |
||
|
Planned |
Completed |
Planned |
Installed |
||
|
Toraiiro Moiiotain (undernroiind) . . . Renteu Mountain (underground! .... |
Machine shop and heat treatment Machine shop and assembly sliop |
177.000 212.000 :i . 5 10 16.500 21,200 |
1U,000 118.000 2.120 1,580 21,200 |
991 MT and 11 Fur 446 MT and .1 Fur 36 Fur 14 MT 3MT |
347 MT and 4 Fu 238 MT and 3 Fu 7 Fur 4MT 1 MT |
|
Tage Mountain (suri'ace) |
|||||
|
\ssenibly s()op |
|||||
|
Total |
430,240 |
313,900 |
1,454 MT and 50 Fur |
590 MT and U F |
|
'MT Machine tool Fur furnace
In addition, there were five surface buildings with a total floor area of 24,200 square feet in- tended for use as warehouses and offices, and seven separate groups of buildings with a total floor area of 342,000 square feet intended for use as dormitories, dining rooms, etc. The Kanunui factory was an old rope factory about 4 miles away from the other sites.
Excavation was begun in January 1945 to adapt the quarries to their new use, and in March 1945 some of tiie maciiinery was put in operation. Tlie first engine was completed in June 1945, but the over-all plans were not completed. Before the war ended approximately one third of the planned area was in production.
Five shafts had been sunk for quarrying. Cov- erings were put over them to keep out the rain, and also to camouflage the position. One slant- ing tunnel was excavated for communication be-
tween the various levels. Labor for digging w l>iovided by a naval maintenance unit which rather unusual because, in general, there appea to have been a lack of cooperation between t Army and the Navy, and this plant was intendi to produce only Army engines.
Organization and Operation
The factory was under the general nianag ment of Y. Nagasawa.
TJie Toiimio jilaiit was intended to niachii <\vlinders, cylindei- heads and barrels, ciankshafl ci'ankcases, propeller shafts, reduction gear co ers, and to do heat treatment. Figure 1 is a la out sheet showing space utilization and numb of machines i)laiined and installed. Photograp 1-6 on the following pages present various vie'? of the machinery and interior. The jiositions fro
wlch the photographs were taken are indicated 01 the drawing.
he Benton ])lant was inlciidcd lo iJi'oducc ar iilating rods, master rods, gears, jigs, and mis- : I neons small parts. Fignre 2 is the space and liz^ition Inyont of the Itcnten jilitiit, Jilso show II I lie number of machines planned and installed. 'iliigra])lis 7-10 on the following pages show or of the machinery. The photographer's po- iii in each case is shown on the drawing. lu' Knnnnia plant, above ground, was the site I ill assembly, although it had originally been il lued that assembly would be done under- mid. The Yuba and Tage works were rela- ]-]y small and only a few pieces of equipment 1' installed.
total of 1075 machine tools were acquired
1 the various works — 76.5 from Musashi, 7G
■ I Omiya, 88 from Yokkaichi, and 146 from
•iiibine known as Nippon Nainenki. Of these,
jD, 604 were installed.
ilans called for 14 test cells, but only 2 were coipleted. They were above ground, .so ventila- lai)n was not a problem.
imployment reached a maximum early in iijust, 1945. The total for all the works was as fo iws :
|
Direct E Regular Soldier Student |
mployees : employees : |
2,497 , 876 300 |
3.673 |
|
Indirect Regular Soldier |
1,642 |
||
|
Student |
387 |
2,029 |
|
|
Total |
. 5.702 |
and Omiya plants, were crankshafts, crankcases, reduction gear housings, and volute casings.
I'rodnction of other parts was ])lanned but not accomplislied.
The plans also called for jn-oducf ion of 300 engines ])('!• niontli. Actually, liolli new antl re- jiaired engines turned out in 194.") wore as fol- lows :
|
June |
July |
August |
Total |
|
|
New engines |
] 18 |
4 25 |
5 12 |
11 |
|
Kepaired enginea |
55 |
|||
|
66 |
Repairs were made on engines that had been improperly assembled by unskilled workers at other plants, and on engines that had been dam- aged in bombing attacks at other places.
No research or experimentation was carried on at this plant.
Effect of Attack
There were no direct attacks on the subject plant, and officials felt no concern over the pos- sibility of raids. That part of the underground works with the shallowest protection from above was 180 feet below ground.
Area attacks, however, had an adverse effect on production. For one week after the area at- tack on Utsunomiya City, worker attendance fell off about 20 per cent. There was no serious ])ower interruption resulting fioin area attacks.
Plant officials said that difficulty in obtaining parts, due to attacks on other plants and to poor transportation, caused a slowing-down of pro- duction schedules.
liirteen per cent of the regular and soldier
saloyees woi-ked on two shifts of ten hours
1 1 and the remainder worked on one ten hour
'I t.
Pi'duction
nly part of the engine components were pro i«!d at this plant. These included crankshafts, CTfkcases, reduction gear housings, certain rods an gears, cylinders, cylinder barrels and heads, vo^te casings, etc. The parts produced by this Phit for other plants, including the Hamamatsu
Operational Difficulties
The plant manager complained of very serious operational difficulties that had not been over- come: underground areas were cold and damp, causing extreme discomfort to the employees; the atmosphere was foggy from the dampness, making visibility very poor; all machinery was constantly subject to corrosion unless the greatest precautions against it were taken. One difficulty that was not encountered during the war was cave ins, although there have been several since the war ended.
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Photo No. 1. Crankcase shops, Tomiira plant at Oya Works.
Photo No. 2. Crankcase shop, Toniura plant at Oya Works.
6
Photo No. 3. Cylinder head shop, Tomiira plant at Oya Works.
Photo No. 4. Cylinder assembly shop, Tomura plant at Oya Works.
7
Photo No. 5. Cylinder barrel shop, Tomura plant at Oya Works.
Photo No. 6. Heat treatment shop, Tomura plant at Oya Works.
Photo No. 7. Articulating rod shop, Benten plant at Oya Works.
Photo No. 8. Gear shop, Benten plant at Oya Works. 9
Photo No. 9. Entrance to Benten plant at Oya Works.
Photo No. 10. Jin and tool shop, Benten plant at Oya Works.
10
3 troduction
SHIROYAMA
[u December 1044, tlie Nakajima Aiicraft Co. nted to dispei-se the airframe production fa- ijities of its Utsunomiya plant, but the Munitions [iiistry refused permission, saying it was not it necessary. Finally, in March 1945, permis- sn was granted and dispersal to underground rerns at Sliiroyaimi bei;an. Tliis plant was op ited in conjunction with the Oya plant, pre- iisly discussed.
Planned production at Shiroyama was three iij; assemblies and three fuselages per day but the end of the war only four of each had been npleted. Manufacturing began late in April I."). The machine shop started first, then com- lent manufacture, and in July, wing and fuse- I e assembly began.
S'early all assembly facilities were to be dis- sed from Utsunomiya to Shiroyama, but some re to be retained at Utsunomiya because the I ice at Shiroyama was inadequate.
ganization
)f a planned nineteen units in the works, with (total floor area of ()4!),7()0 square feet, only
ht units with 333,000 square feet of floor area me completed. Four of these (38,900 square
t) were used as warehouses for tubing, ex-
ded parts, duralumin bais, oil, and paints.
fhe largest of the other four units that actually ^ into production was the Otomeyama plant (•4,500 square feet) where sheet metal parts •Me produced. Photographs 11-14 show the en-
nces and some of the presses.
jfhe next largest was the Watanabeyama plant (v500 square feet) housing the wing and fuse- ie assembly and jigs for tail parts. Photo-
graplis 1.") l(i show jigs and some of Ihe main air- frame parts.
Tlie Kaneiriyama plant (86,000 square feet) contained machine tools and electric heat treat- ment furnaces. Some space was used as a ware- house. See photographs 17-20.
The Tochigiyama unit, devoted to wing spar manufacture, contained only 14,100 square feet, and all machinery had been removed at the time the inspection was made.
An ovei'-all layout of all parts of the Shiro- yama installations is shown in Figure 3. The po- sition of the photographer in taking each of the photographs on the preceding pages is indicated on the drawing l)y numbers t-orrcspondini; with numbers on the photographs.
In July 1945, when dispersal was still going on from Utsunomiya to Shiroyama, the combined number of employees was 21,117. This figure in- cludes both direct and indirect employees; no further break-down was available.
Production
The only airplane type intended for production at Shiroyama was the Army fighter Frank (Jap- anese Ki-84). Nearly all sheet-metal parts and some machined parts were to be made here. Other machined parts came from the Tochig and Ot- awara plants of Xakajima but subcontractors suj^plied 50 percent of all parts other than sheet- metal pai'ts.
Actual airframe production amounted to only four wing assemblies and four fuselages before the end of the war, but inasmuch as production was just getting under way, those figures can scarcely be used as any measure of capacity for the Oya plant. Three wing assemblies and three fuselages per day was the goal that had been planned.
11
Photo No. 11. Tunnel entrances (Otomeyama plant), Shiroyama.
Photo No. 12. Tunnel entrances (Otomeyama plant), Shiroyama.
12
Photo No. 13. Sheet-metal press (Otomeyama plant), Shiroyama.
Photo No. 14. Part of 20-ton press (Otomeyama plant), Shiroyama.
13
Photo No. 1'?. Fuselage assembly shop (Watanabe plant), Shiroyama.
Photo No. 16. Horizontal stabilizer jigs (Watanabe plant), Shiroyama.
14
Photo No. 17. Machine tools awaiting installation underground, Kaiieiriyama Works at Shiroyac
Photo No. 18. Warehouse and stockroom, Kaneiriyama Works at Shiroyama.
15
Photo No. 19. Machine shops for airframe parts, Kaneiriyama plant in Shiroyama.
Photo No. 20. Electric heat treatment furnaces, Kaneiriyama plant at Shiroyama.
16
OYA ENGINE WORKS
|
NO |
AREA-SQ.FT |
PLACE |
DESCRIPTION |
|
100 |
102,000 |
Otomeyama |
Sheet metal pai^i* |
|
103A |
4.600 |
Tochiglyama |
Warahouae- Tubing and entruded ^larla |
|
103B |
14. ISO |
-oil and paint |
|
|
lO-V |
6.000 |
-duralumin bar |
|
|
105B |
I9.B00 |
Not complete-Sub-assemblj |
|
|
106 |
€^850 |
Tochiglyama |
|
|
107 |
87.200 |
Kane Ir) yam a |
Maohine shop and h«st Ireattnant |
|
108 |
20.200 |
Tochigiyama |
Not tompl«te-hMt tr«atm«fit |
|
110 |
ae.500 |
Waranabeyama |
Sub-assombly -rtnng and fus«lage |
|
112 |
21,200 |
Maru3hoyafn« |
Not complete -sub-asiftmbly- cowlinj |
|
113 |
99,000 |
|
|
|
It4-A |
21.200 |
tnarlyama |
■■ -ShMt matal parts. vyarchou^« |
|
IK-B |
n.TOO |
||
|
115 -A |
28.300 |
||
|
115-B |
Z6,fiOO 1 |
||
|
118 |
14.200 |
Maruhachiyama |
Warehouse -oil |
|
119 |
17.700 |
Tochigijama |
5ub-assernbly-v<ing5p»r |
|
120 |
30.100 |
Tanjayam* |
Not complete-aub^ksemblyviin^ |
|
123 |
23,400 ' |
||
|
Total |
649.700 |
U.S. STRATEGIC BOMBING SURyEY_
UNDERGROUND PLANTS NAKAJIMA AIRCRAFT CO.
FIGURE i
)um o . 41 irua p. le)
ASAKAWA
This plant was a dispersed location of the (isaslii Works of the Makajiina Aiiciaft ("o. and IS located in Die steep hills on the west edye of akawa villafie which is two miles west of ichioji in Tokyo prefecture.
It was jilanned that tiiis plant would liave 3,000 square feet of floor space and l,l!0() nia ine tools for the production of 300 engines per )ntli and tJiat it would be in production by July 15. However, at the end of the war in August, ly G out of 31 tunnels were completed, with an ?a of IT)", 000 square feet excavated. Thi-ee hun i(i tiiiity machine tools were in place and liad m producing engine parts since July. Xinety- e otiier machine tools had been delivered to tlie e but not installed.
The tunnels were laid out in tliree sections in a id network (Figure 4). No previous tunnels or nes had been in existence here so that the entire eavation was new. External evidence of this mt could be seen in the piles of spoil and in the w uncamouflaged surface buildings which were ?d as offices and storehouses. The tunnels were approximately 15 feet wide d 12 feet high and varied in length from 100 ■t to 1,200 feet. Because the rains caused tJie ifs of tlie tunnels to collapse in at least six ices, extensive timber shoring had l>een set. The Nakajima Co. expected to manufacture ^ine parts in tlie underground woiks, with final ienibly to be carried out in dispersed surface ildings farther up in the hills. By 1.1 August t5 about 10 engines liad been completed. In dition there were about 300 crankcase castings )red in Tunnel 1, great stores of cylinder heads Tunnel 3, and many other stocks of engine parts machining. There were IS engines in process assembly in two dispersed small hangar-type Hidings.
For the conveyance of parts inside the tunnels, 'o of the tunnels had narrow-gage tracks while
^
a third had a roller conveyoi- the length of the tunnel. Only h.ind methods were available in the rest of the plant.
Most of tlie usual types of machine tools were installed; engine latiies, turret lathes, drill presses, shajiers, phniers, giinders, etc. Eighty percent of the 330 installed machine tools were American made, with such familiar company names as Brown and Shariie, (Mnciunati, Warner and Swazey, American Machine Tool, Bullard, and others in evidence.
The six tunnels in o]ieration were used for ma- ciiining the following:
Xo. 1. Cylinder heads.
No. 2. Cylinder barrels.
No. 3. Crankshafts.
No. 4. Propeller shafts.
No. 5. Proi)eller shafts.
No. G. Engine accessories.
The chief problems of operating this plant were caused by wet floors and moist atmosphere. The floors in all tunnels examined (Nos. 1 through 6) were wet and in several places were under several inches of water. This caused much illness among the workers and serious corrosion of tiie machines. At the time of inspection the machines weVe covered with a layer of grease and waxed paper in an effort to preserve them. Even so, many of them were seriously corroded. Photographs 21-25 show machine tools and parts in the plant.
The manager of the jilant reported that a short- age of new cylinders made it necessary to employ used cylinders in the manufacture of engines. This was veritled in the assembly shop where the stock of used cylinders slightly outnumbered the new cylinders.
Asakawa was inspected on 24 October 1945.
714387—47—3
17
GENERAL ARRANGEMENT OF ASAKAWA (UNDERGROUND) PLANT
Corrected to 13 JULY 645
JfflSHU HIGHWAY
|
AREA CHART |
COM^mON 10 tiin a«« |
|||
|
^yssstr |
TOTAL |
|||
|
A |
131,116 |
57,178 |
188.294 |
80X |
|
B |
80,429 |
29,837 |
110,288 |
eox |
|
C |
90.408 |
10,483 |
40.871 |
6S« |
|
TOTAL |
241,953 |
97.478 |
339.431 |
78X |
T<^''
Sf^
UNDERGROUND FACTORY
1^^;^ CONTOUR llllllllllllll SURFACE BUILDING
|
LEGEND 1 |
|
|
PARTS MACHNED |
|
|
SHAFT GEARS |
|
|
REPRODUCTION GEAR |
|
|
PUMTIMrrOEAR |
|
|
CAM BOSS |
|
|
SUPERCHARGER 6EAR |
2S
^®
NOTE:Sli*e1®of2 figure 4
UNOERGROUNO PLANT
ASAKAWA
aENERAL AfOUNSEHENT
UNDERGROUND FACTORY
CONTOUR
SURFACE BUILONG
NOTE-.ShMt®of 2 RGURE 4
us. STRATEGIC BOWBWC SOHVFT
UNDERGROUND PLANT
ASAKAWA
GEICRAL ARRANOEMENT
IltSIT O- 4t(rm«^ 1*>M
GOKAN
The (ioknii ])lant of the Nakajiiua Aircraft Co. ■;ir Nuuiata in (inimiia jjrefectiire was inspected ('ai)tain Kicliarilson, the intelligeuce officer tlic oSTtli Infantry Regiment, 97th Division. II' lollowini; data were obtained from liim: jSi.xteen tnnnels, each about 600 feet long, had en excavated by 5G5 Cliinese prisonei's of war 10 were housed nearby in a labor camp. Some 0 machine tools had been installed in the tun- Is while many other tools were stored outside.
awaiting the completion of new areas. In parts of the plant, there were double rows of machine tools.
The floors at Gokan, as at Asakawa, were gen- erally wet and, while .some of the machinery was protected with grease and tarpaulins, many other machines were severely rusted.
A .semiunderground plant was l)eing built near- liy to assemble the airframe parts which were to be machined in the nndergi-ound section.
19
Photo No. 21. Asakawa underground plant.
20
Photo No. 22. Asakawa plant cylinder heads awaiting machining. Note roller
conveyor.
Photo No. 23. Asakawa plant. Cross-tunnel used for storage of engine parts.
21
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Photo No. 24. Asakawa underground plant.
Photo No. 25. Asakawa underground plant. 11
YOSHIMATSU
One III' Ilic iiKisI ;iii\ Mined |il;ni1s seen in Japan ivas till' Voshinialsn ent;iii(' (ilant of Nakajima ociitcd iH'ar .Malsiiyaiiia, '■'<- miles noitlnvest of Tokyo. Tliis jilant. wliicii was (lis]KMsc(l fi-om the Omija Works, ^vas SO peicent coniplele and -was in ])rodii((ioii from lo .huie until the end of the win. Altlionj^li it was planned to make eomplete iigines a1 this plant, only the nnicliininy of parts ivas actnally earried ont.
The Japanese aircraft indnstry was not tlie first irganization to i^o nndeij^ronnd at ^Matsnyama. riiat distinction jioes to a jironp of cave dwellers )f abont 1, .")()() years ajio. More than 100 caves pockmark tlie face of the cliff in which the air- raft tnunels aie located. Each of these caves has in entrance aliont 4 to 5 feet square which opens into a heniisjdierical room abont 8 to 10 feet in iiameter ( l'lioto};iaphs 20 and 27). These caves ivere the dwellintis of some ancient tribe.
Farther alony tlie clitT is anotlier cnriosity — the Madman's Hotel, which is an underground house tarted by Ninekichi Takaliashi in Nishi-Yoshimi- inura. Tlie house was begun in the thirty-seventli rear of the reign of Meiji (1904) as a financial reuture. He expected that it would take three enerations to complete but by that time it would 36 such a curiosity that visitors would pay to see <uch a place and the Takaliashi family would 'ventnally become financially independent.
He worked for I'O years on the project and had 2 large rooms, 1 small room, numerous corridors, ind the staircase to the second floor already ai'ved. The entrance was flanked by 2 Grecian olnmiis carved into the cliff si<le and led into the lobby, a room about 10 feet by 20 feet with the staircase in the rear center. The living room, i by 12 feet had stone tables, chairs, and fixtures. The dreams of Takahashi were not realized as his 5on abandoned what he considered to lie a mad- man's project when the father died.
Both of these projects served a useful purpose for the Japanese in 104."). as they inspired the onstruction of an underground aircraft plant in this hill of sedimentary volcanic ash.
On 15 January ]()4.">, this factory received orders to go underground and excavation was started shortlv thereafter. As sections of the
tunnel areas were comiileled, maciiine tools were installed and the machining of aircraft engine parts was begun. The first actual work was done on 1.") June and continued nnfil the end of the war.
Tlie total planned area of this plant was 353,000 square feet, to be spread over six areas (Figure 5 1 . The first five areas were completely excavated and tliree tunnels of the sixth area were com- pleted, making a total excavated area of about 320,000 square feet. The total length of tunnel amounted 1o approximately 33,000 feet.
Each tunnel was 13 feet wide and varied in height from 11 feet to 13 feet to accommodate the use to which the tunnel was put. (Photographs 28-36).
The tunnels were fairly dry due to the peculiar desiccating quality of the volcanic-type rock through which they- were carved. The tempera- ture remained fairly constant underground throughout tlie year. Area No. 5 was shored up by timbers but most of the remainder needed no siqiport. In many places concrete floors had been laid.
Four hundred fifty machine tools had been brought to the site but only 300 had been installed in the tunnels. Machines were set in the tunnels ill single rows.
Corrosion of equijunent became a problem almost at once. To combat this condition it was made the responsibility of each workman to keep his machine from rusting. To prevent corrosion, finished parts were removed from the tunnels im- mediately upon their completion.
Plans called for the manufacture of 300 engines per month in the underground plant, with final assembly in dispersed buildings in and near Matsuyania. Actual production, however, con- sisted only of master rods, cylinder heads, cylinder barrels, and crankshaft counteilialances. Between 200 and 300 of each of the above parts were com- pleted by 15 August.
Evidence of this work was seen in the piles of master rods, counterbalances, and cylinders that were stacked lieside the machine tools and in stor- age tunnels.
23
Eventnjtl employnieiil lieie would have been J;,000. Uowever. ouly -"iOd weie iKtiially at work undei-ground in Aiijiiist. K. Hiruta was plant manager.
Transportation of parts to and from the plant was by truck.
Several tnnisiial featines were noted in this plant :
1. In area No. i. nine heat treatment pits were being dug in the tunnel floor. Each pit measured S feet wide, t! feet deep, and lo feet long.
2. Tall machines Avere coiiiUersunk into the floor of the tunnel so tliat the largest ma-
chines seen anywhere underground were i
place here. .">. A power substation of three 2o0-kv.= i.
transformers was built for each of the e
completed areas. 4. Tunnel cross sections varied to suit the m\
The entrances to Sections 1 and 6 were iu sh i cliffs at least 75 feet high. The whole establ ment was well concealed except for a built area of 5 surface buildings (warehouses, offn etc.) near the entrances to Number 4 area.
Yoshiinntsu was inspected on 13 and 15 Novi ber 1!)45.
I
24
I
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m^
^5^-^
Photo No. 26. Ancient caves at Yoshimatsu.
Photo No. 27- Close-up of ancient caves at Yoshimatsu.
25
Photo No. 28. Entrance to Nakajinia tunnels at base of cliff, Yoshimatsu.
I'hoto No. 29. Entrances to tunnels, Yoshimatsu.
26
Photo No. iO. Machine tool in process of installation, Yoshimatsu.
Photo No. 31. Tunnels at Yoshimatsu.
27
Photo No. 32. Machine tool in process of installation, Yoshitnatsu.
Photo No. 33. Machine tools in position, Yoshitnatsu.
28
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Photo No. 34. Machine tools standing in water. Landslide had formed a dam near entrance^
Photo No. 35. Three 250-kv.-a. transformers, Yoshimatsu. *' 29
Photo No. 36. Heat treatment pits under construction, Yoshimatsu.
30
YABUTSUKA
The Yabiilsuka aiifiiuue plant, located 6 miles (ulliwest of Ota, Gumma prefecture, was a ilis- ersed location of the Ota "Works of the Nakajima ircraft Co.
Tt was not possible to inspect the tunnels of lis ]ilant on the date of visit, 13 November 1945, pcause all entrances had caved in. The local 'i|ianese attributed the collapse to the torrential ( lober lains and denied that any explosion had ;ilcd them. At several entrances it was possible
liiok over the landslide into the tunnels where
rcmld be seen that water was standinj; from 1 feet deep.
Thirty tunnels, each 13 feet wide and 11 feet hifih, were completely excavated and shored up with timbers. This represented one-half of the |)rojected ai'ea.
Excavation was started in January 1945 by 1,500 men working on a 10-hour shift. Planned lay-out is shown in Figure 6.
No machine tools were installed or even brought to the site.
This plant was almost inaccessible. Only one very narrow road which would barely permit pas- sage of a jeep led to the site of the plant.
YUSENJI
\ usenji, 1 miles west of Komatsu in Ishikewa efecture on the northwest coast of Japan, was dispersed airframe plant of the Handa Works the Nakajima Aircraft Co.
The underground areas of tliis plant were the riad and irregular caverns of ancient firebrick id modern stone quarries. In prewar years many the modern buildings of Tokyo and Osaka had in constructed fi'om building stone dug out of site.
>f a planned area of 211,000 square feet, about "000 scjuare feet were ready for use, while 100 400 machine tools planned were in operation. The jilant was designed to produce small air- Ibme parts, metal fittings, and similar items for e C-6 scouting plane. Production on a small ale began late in June 1945 but only a few parts ?re completed by the end of hostilities. The con- rsion of the caverns for aircraft production be- iin in February 1945 under Navy supervision and jnipletion was set for the end of September, but ily 30 percent progress had been made by 15 iigust.
An extensive network of tunnels and quarries is hidden under the hills witii only a few entrances and some new spoil to reveal their existence to the photo interpreter. Small entrance tunnels about 9 feet wide and 6 feet high with extensive and heavy shoring led into the main galleries which were of irregular shape (Fig. 7).
Concrete bases had been laid on which to mount the machine tools and the cavern floors were dry.
Yusenji was easily accessible by highway and electric raili'oad from Komatsu. The actual tun- nel level is only a few feet above sea level. .
Of all the underground factories seen, this one seemed among the best from the standpoint of transportation, concealment, and working condi- tions.
One half mile north of the Nakajima site was another hill with a similar network of caverns, which housed great stores of munitions that were being removed by United States troops on 20 November 1945, the date of inspection.
31
LAYOUT OF YABUTSUKA PLANT
U.S. STRATEGIC BOMBING SURVEY
UNDERGROUND PLANT YABUTSUKA
FlCjUfiE 6
THin O - 41 IFiCB (I IJI ^
o
.^.U
5 ENTRANCE
YUSENJI UNDERGROUND PLANT
OF
NAKAJIMA CO.
HEIGHT VARIES FROM 5i FT TO 16 FT
[ SLANTED LI^CSAfiE•4 TUNNEL GROUP MACMNE TOOLS KSTALLEDJ
i^*3 ENTRANCE
USSTRATEGC BOMBING SURVEY
YUSENJ UNDETfGROU\D PLANT
(OSPEHSED FROM HANQA VKJfilS OF NAKAJIMA-) F)&-r
T10*T O - «T iru> K HI Ho. 1
PART II
UNDERGROUND PLANTS OF MITSUBISHI AIRCRAFT CO.
KATSURA
The Katsuia plant of Mitsubishi No. 8 Engine Woiks was located at Mameda, one-quarter mile north of Katsuia station, southwest of the city of Kyoto. Not strictly an underground plant, it was au interesting use of a lailroad viaduct lo con- ceal and protect a shop.
The space under the viaduct where it crossed a liighway was enclosed by the erection of mud walls along the steel and concrete trestles. The area thus enclosed amounted to 25,000 square feet.
Seventy two machine tools had been installed and were in operation from June 194.1. The entire plant was used for the machining of all master rods for Kasei 25 engines.
It was evident that the plant had been an effi- cient one. It was clean, well-lighted, and dry, with an orderly arrangement of machine tools.'
In external appearance there was no evidence to reveal the location of this plant to the photo interpreter.
The jilant was inspected on :'.() October 194.1.
OTANI
The Otani plant was a dispersal location of the Mitsubishi No. S and No. 14 Engine Works and wa.s situated at Otani, 1 mile southwest of Otsu, a city 6 miles east of Kyoto.
Two abandoned railroad tunnels, 2,1(50 and 2,1'OU feet long respectively, were used as gear- tutting and grinding shops for the aforementioned Iilants. Thirty-six different kinds of gears were machined here on 2S6 machine tools belonging to ^'o. 8 Works and 2.5 tools belonging to No 14 Works.
Installation of machine tools began 16 JIarch 1945 and was completed in April. Full produc tion was carried out for about 2i/o months.
A total of 700 persons was employed in the
plant. Many of the employees were girl students who "worked very hard but not too well.". More than half of the machine shop employees were students.
The tunnels were reasonably dry but the man- :iger leported that there was always trouble with moisture, which caused worker illness and cor- rosion of machines and tools.
Six wooden buildings were erected in the valley at the southwest end of the tunnels. The.se build- ings were to be used for heat treatment, carboni- zation, and copper plating but were not completed by the war's end. They were not camouflaged nor was it intended to do so.
The plant was inspected on 31 October 1945.
KIYOTAKI
Kiyotaki was a dispersal of Mitsubi-shi No. 14 lMij,'ine \'\'(irks and was located in two abandoned **'ieetcar tunnels 5 miles west of Kyoto.
The plant was very similar to Otani and came into production in May 1945, just ten days after
714387—47—4
Otani. The tunnels were 1,970 feet long and housed 120 machine tools.
Machining of exhaust valves was the only opera- tion to take place here.
33
KUKURI
The Kukuri plant of the Mitsubishi No. 4 Engine Works was located in the hills three miles southeast of lliromi, about 20 miles northeast of Nagoya (Fig. 8).
An elaborate netwoi-k of 38 tunnels totaling 23.000 feet in length was excavated in a ridge of sedimentary-type rock. The total planned area was 360,000 square feet, of which 270.000 square feet were completed. In cross section the tunnels measured 16 feet wide and 11.5 feet high (Figs. 9 and 10).
During construction the tunnels were cut en- tirely through the hill so that the machine tools could be handled directly into each tunnel. After the machines were in place it was intended to close
and conceal the entrances to all but three tunnels wliich would then become the only entrances.
One hundred sixty-four of a planned 800 ma chine tools were installed underground. Thesi machines were lined along both sides of the tun nels, leaving an aisle about four feet wide in th' center.
This plant was supposed to manufacture engine liut no actual production was achieved.
These tunnels were among the better ones see in Japan. They were very dry, well laid ou' had smooth floors, and seemed roomier than mam others (Photographs 37-40).
Kukuri was inspected on 3 November 1945.
I
34
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35
UNDERGROUND PLAI
li...«| PILOT TUNNELS
^^ ENLARGING UNDER CONSTRUCTION'
^^ ENLARGING FINISHED
IQO 200 MO
U.S. STRATEGIC BOMBlNG SURVEY
KUKURI UNDERGROUND WORKS AUG. IS, IMS
Turn 0- «T(rK»p. Ml*
TltSRT O - 41 (Pi» p. SB) No. 1
\
3 3
0 JS
01
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37
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75
3
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38
Photo No. 39. Kukuri plant. Two long rows of machine tools
Photo No. 40. Kukuri plant. Machine tools being installed.
39
NIKODA
The Xikoda undergroimd plant of the Mitsubishi No. ") Airframe Works was situated in the hills 6 miles west of the city of Ueda in Nagano prefec- ture.
Orders for dispersal into the Ueda area were received by Mitsubishi from the Army in April 1945. The actual excavation of the underground plant was supervised by the Army. The techni- cians in charge came to Nikoda after completion of the Central Army Underground Headquarters at Matsushiro. between Nagano and Ueda. Three areas were planned with 17, 6, and 15 tunnels, )-espectively. Each tunnel was to be 13 feet wide and 10 feet high and shored witli timber to prevent roof collapse.
Tlie production goal was an output of 50 Ki-83 aircraft per month in conjunction with a nearby semiunderground plant. However, no production
was realized and no machine tools were install At the war's end the underground plant wa.s per cent complete, the power installations were per cent complete, and the semiunderground pli was 45 per cent complete, with 33 buildii erected.
The schedule called for total completion of underground plant in September 1945.
At the time of inspection the tunnels were ■> and damp. When asked what precautions agai worker illness and machine corrosion had b taken, the plant manager replied that there \ no time to study any problem other than that getting the machines underground.
Transportation of material to and from plant was expected to be by truck only.
Tlie inteiviews and inspection were conduc on IL' November 1945.
MATSUMOTO
The -Mitsubishi No. 1 Airframe Works had a combined underground and semiunderground I)lant under construction several miles southeast of Matsumoto in Nagano prefecture.
This plant was designed to produce 20 experi- mental aircraft per month. The planned area was 25:i,000 square feet, all of which was excavated, but only 40 percent of it was ready to receive ma- chine tools. No machine tools had been installed, however, and there was no production.
Plans were made in February 1945 to go under- ground at this location and work liegan on the tunnels in April under the supervision of the Army. Although the original survey conducted by the Army concluded that no shoring would be needed, the rock proved unsafe and extensive shor- ing with timber became necessary. It was planned to use concrete to support the weak spots in the tunnels but a shortage of cement prevented this. In fact, timber also became scarce very soon, when three times as much timber as calculated was needed.
An insufficient number of mining engineers added to construction problems.
Transportation, however, proved to be the chief problem in going underground, first, in the move- ment of machine tools and equipment from
Nagoya to Matsumoto and later, to transport : terials to the underground site. Transport to underground plant from Matsumoto was by tri over narrow and poorly maintained roads.
The schedule called for 50 percent complet and the beginning of production in June 1945 i for total completion in August. Due to the d culties already enumerated, only 40 percent o pletion was reached in August.
The familiar comment was again stated he the great haste of dispersal left only time to c sider tlie basic problem of getting the mach tools underground and out of reach of the An ican bombers. Such serious considerations protection of machinery against corrosion, vei lation, and worker health were postponed. Even ally, Mitsubishi hoped to solve these problems lieat and ventilation.
I'arts fabrication for Ki-83, Ki-67, Keppn, a Taiyo was to take place underground. Fii assembly was to be accomplished in the 150 sei underground buildings in the surrounding hi Testing was to be done in semiunderground bui ings at nearby Murai airfield.
The date of inspection of Matsumoto was November 1945.
IfD
11(
40
OGAMI
Jhe Ogami imdergiound plaut of Mitsubishi No. Airframe Works was located 10 miles south of ibka in Toyama prefecture. A semiunder- luud plant at Haiinyamura was operated in se conjunction with Ogami.
I'his plant was still under construction by the ernment and had not yet been taken over by subishi. The excavation was 30 percent com-
plete Init progress toward actual production was only 10 percent advanced.
Tunnel cross sections measured 13 feet by 10 feet after shoring had been erected. The maxi- mum tunnel length was 1,150 feet. No machine tools liad been installed.
Ogami was inspected on 18 November 1945.
NUKATANI
'lie Nukatani underground plant of Mitsubishi 12 Engine Works, four miles south of Kana- •a, was one of the most unusual plants to be ted.
"he necessity for performing a certain amount mountain climbing to an altitude of 750 feet t a strange air to the Nukatani underground ut. The plant was accessible only on foot up larrow, recently constructed road which was ihed out in many places by the heavy October
IS.
Lucient caverns, from which the people of a t age extracted tire brick, were at first intended the Japanese Navy to be used as a Naval anal. Early in April 1945, the Navy started ■k on making the tunnels and caverns usable late in the same mouth abandoned the project turned it over to Mitsubishi for aircraft- ine production.
litsubishi subcontracted the construction of plant and the company was to be reimbursed r by the government. Because of the inacces- lity of the site, it became necessary to initiate rge civil road building project to the plant, a dential building program, and a bridge con- ctiou program to span the steep chasms to the t.
itsubishi did not approve of Nukatani but was er constant pressure from the government to d a plant at this location. The company's obction was based ou the knowledge that, in K itioii to being inaccessible, the plant also *''ild probably be out of production for four Ti'itlis each year because of the heavy snows in liwest Honshu duiing the winter months.
Furtheimore, the problem of transportation of both workmen and products presented even more serious problems than those which already had caused great difficulty in other more desirable locations.
Despite these considerations, the plant was con- structed to house one of their more important works to produce exhaust turbines and fuel injec- tion pumps. Beginning 10 July 1945, machine tools were laboriously pulled up the mountain road by hand and roller means and by the end of the war 146 machine tools were in place. In addition, 253 tools were stored at the base of the hill in shrines and schoolyards. Almost all of the machine tools were of American make, because of the high degree of accuracy required in making these parts.
Actual production had not yet begun but was anticipated within a short time.
The caverns and tunnels were very dry and in many places concrete floors were laid. It was not necessary to shore up the caverns as natural pil- lars and the strength of the rock itself were sufficient support.
Located on many levels throughout the moiin- tain, the tunnels ranged in elevation from 650 to 800 feet above sea level. The average cavern was 20 feet wide while the height varied from 12 to 20 feet (Fig. 11).
During the early summer of 1945 the Japanese Navy made aerial reconnaissance of the area and reported that the new road revealed the location of the jjlant.
Nukatani was visited on 19 November 1945.
41
SHAKUTANI
Shakiitiiiii, located one mile west of Fukui city ill Fnkiii prefecture, was an underground disper- sal of Mitsubishi No. IS Engine Works.
This plant was an elaborate arrangement of caverns and tunnels consisting of four completed underground areas as well as a semiundergrouud plant (Fig. 12). So skillfully were the semiunder- grouud plants built into the hillside that one building was almost passed during an inspection trip before it was noticed.
Caverns from which Shakutani stone — a famous Japanese building stone — had been removed, fur- nished the s])acc for this plant. Work was started in February Iflio to ready the caverns for use by the Mitsubishi Co. and the movement of machinery into the plant began in April.
The machine tools, of which !'!)(! had been in- stalled, were only in the process of alignment and testing, and it was claimed liy the company that no production was achieved.
This plant was well advanced (considered percent complete by the Mitsubishi Co.) by t average standard of underground plants. In adi tion, it was near the local ground level and w easily accessible by highway.
The caverns and tunnels were very dry, nev; theless, most of the machine tools were corrodt The caverns followed the seam of building sto and were therefore of varied size, on many diff( ent levels, and of generally high ceilings (12 to feet). Only one landslide occurred during t October rains.
The machine tools for one area were lower into the tunnels through a vertical shaft 60 fi long.
This jjlant was to produce gears and light mei parts for engines.
The date of inspection was 21 November 19
SABAE
Stone ((uariies :?()() feet above ground level pro- vided the setting for the Shinyokoe plant of the .Mitsubishi No. 18 Engine Works at Sabae in Fukui iirefeclure.
This plant consisted of two sections, the first being in the stone (juarries well up into the hill, the second ((insisting of a grid of newly excavated tunnels at ground level at the base of the hill.
The (piarry section was a series of caverns with large rooms and lofty ceilings. One room was fully 7."> feet long. 2.") feet wide, and IS feet high. Concrete floors had been laid in many places and throughout the tunnels it was exceptionally dry.
As may be seen from the attached drawings, (Figs. 13A and 13Bj the caverns are not syste- matic but wind about in eccentric patterns and are on many levels. At one place a broad flight of stone stairs elicited the comment "It's just like a cathedi'al underground."
This upjier section of tlie jjlant had been wired for electric jiower. Two 200-kv=a. transformers and a switchboard had been installed.
Twenty six machine tools were in position in lireparation for the jiroduction of cylinder heads. A large stock of iiimiachined cylinder heads was on hand Imi it was maintained liy company offi-
cials that no productive work had emanated frc this plant by 15 August 1945.
The newly excavated tunnels near the base the hill were among the best of this type that we seen (Fig. 14). The rock was dry and solid ai no supporting timbers were needed to reinfoi the roof. Some extremely roomy tunnels ( undergiound standards) were inspected. Sever tunnels were 20 feet by 10 feet in cross sectic dimensions. A total of 13 tunnels, each about 3 feet long, had been completed but no machine too were installed.
The entire lay-out of this plant was excellent concealed from the standpoint of aerial reconnai sauce. Only a very small amount of spoil wi visible and the roads were almost completely coi cealed by trees. The plant was accessible t Sal)ae by an existing road.
The impression gained was that this plai would have become a good ]iroducer of engin parts within two months and that it would hav been comparatively safe from direct bombin attack.
The Sabae area was inspected on 21 Novembe 1945.
42
UNDERGROUND FACTORY MITSUBISHI CO.
[:;:|:;:j COMPLETED
I jiN pfiocess
PLANNED
NOTE 9 HOLES- TOTAL FLOOR AREA" IC^eOOSO.FT (NO 20 TO 29 HOLES- 146 MACHINE TOOLS) TOTAL AREA - 395^00 SO. FT ELEVATION IN FEET
US. STRATEGIC BOMB SURVEY
UNDERGROUND PLANTS NUKATANI
LAYOUT OF SHAKUTANI PLANT
UNDERGROUND
|
NO Of HOLE |
AREA |
OOfMACWC IDOLS, |
|
1 |
34^32 |
31 |
|
2 |
34^62 |
35 |
|
3 |
wee |
IS |
|
4 |
4M20 |
217 |
|
TOTAL |
I23k094 |
296 |
SEMI-UNDERGROUND
|
NO |
WIOTH- LENGTH |
AREA |
USED FOR |
|
Wi |
2297 X 6560 |
1506.83 |
OFFICE |
|
V* |
4694 X 32.80 |
1506.83 |
offk;e |
|
»4 |
45-94 X 65,60 |
3013 66 |
WAREHOUSE |
|
w. |
32.80 X 45,94 |
1506 83 |
- |
|
w. |
2297 X 65,60 |
1506.83 |
■ |
|
V* |
32.60 X 4594 |
1506.83 |
OMNG HALL |
|
*7 |
45,94 X 65,60 |
300 66 |
WAREHOUSE |
|
*? |
4594 X 65,60 |
30S.66 |
■ |
|
•* |
4594 X 65,60 |
30(366 |
• |
|
*« |
4594 X 6560 |
3013.66 |
" |
|
Wii |
4594 X 65,60 |
300.66 |
■ |
|
*,2 |
4534 X 65,60 |
30O.66 |
■ |
|
TOTAL |
28,629.77 |
||
|
1000 |
0 £000 4000 |
SCALE IN FEET
J S. STRATEGIC BC*tBING SURVEY
UNDERGROUND PLANTS
SHAKUTANI
FWUHE 12 I
r
USHIGAYA STONE QUARRY
LEGEND
ELEVATION ABOVE SEA LEVEL
ROOF HEIGHT
Ua STRATEGIC BOMBINo SURVEY UPPER LEVELS OF PLANT AT
SAKAE
Fie. 13
43
44
il
45
UNDERGROUND FACTORY LAYOUT (machine shop)
•OALi m ntr
.o.
:o!
r<^
I 1 MACHWE TOOL (oM pits of clMning sond uMd
in plodng of nMcMn* tool)
^^g POWER HOUSE EQUIPMENT («wfteti bott ttc.) PASSAGE
HIGHER FLOOR {viry dongtrout in this or«o
a bilow bocous* of lonMidM)
us inMt&it Muem ajBVEV ■
N(SAI UNOERGROUNO WORKS OF MITSUBISHI
1l»t^ O . 4T (PI» t Ml
HISAl
The Hisai plant (Fig. 15) was< ouly one of a series of iin(lei<ii()nn(l plants in tunnels which had been dng j)revi(iusly to obtain sand for abrasives. Tk Navy, Aichi Aircraft Co., and the Sumitomo Co., in addition to Jritsnbishi, had nn<lerground plants here, all of which were to work in conjunc- tion with the Tsu Naval Arsenal in producing air- craft and engines.
The Hisai underground plant, located in the low hills southwest of Nagoya, was a part of the .Mitsubishi No. 3 Airframes Works.
At Hisai, entrances led down to a working level some 40 feet deep. The tunnels had been hol- lowed out of the sandy rock and very little shor- ing was necessary (Photographs 41-47).
Concrete had been laid as machine beds but theie was no otiier paving. The machines were crowded and working sjiace was restricted. The conunnnicatioiis tunnels wei'e served l)y rail and cable c"ir.
The iiiant was very damp. Working conditions were poor, the machines were rusting, and pump- ing was necessary after a rain.
The estimated capacity of the plant when tin- islied was 1,.")()0 workers and .540 machine tools, actually, 300 tools were installed, beginning in ■lune 194.5.
This plant was dangerous in several areas be- cause the tunnels were on two levels and the collapse of sections was imminent.
47
Photo No. 41. Machine tools en route to Hisai.
Photo No. 42. Entrance at Hisai. 48
it
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X
49
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50
Photo No. 45. Interior at Hisai.
Photo No. 46. Interior at Hisai. 51
52
PART III MINOR AIRCRAFT COMPANIES
SOGO DEPARTMENT STORE PLANT OF THE SUMITOMO COMPANY
111 Osaka, tlie si'cond and lliird haseiiieiits of lie Sojjo Co. l>ei(artnu'iit Ston- were used by the
uinitomo Co. for the maeliiiiing of propeller iirts.
Xot strictly an iiiidergroniid jilaiit, the.se base- iciit.s were inspeeted to complete the picture of ic various types of underground installations.
.V total of 167 machine tools operated here for
period of 3 months in wliat appeared to be an ii-derly and well-managed production line.
The machine tools had been lowered into tlie isements througji holes that had been cut in the
sidew;ilk adjoining the building. This work had been carried out at night so as to conceal tlie whole operation. The heavier machines were in the third basement and the lighter ones in the second basement.
In great contrast to the tunnel plants, these basements offered no unusual ojienitional prob- lems, were clean, light, dry, and efficient. Further- more no external evidence was visible to (he photo interpreter of the actual work taking place here.
This plant was visited on 30 October 194;).
HANDA
The Handa underground plant of the Sumitomo II. was a part of the network of underground ants southwest of Tsu (40 miles" southwest of agoya) to serve the Tsu Naval Arsenal (Fig. 16). This plant was similar, but superior to, the isai plant of Mitsul>ishi whicli adjoined it. The iiinels were enlarged out of tunnels which had ■en dug previously to furnish sand for abrasives. Frequent shoring, cement spray on the walls, ■ip guards over the maciiines. concrete floors, joping levels, and drainage gutters were char- 'teristics of this plant. Pumping was necessary
on occasion to lemove tlie water. (Photographs 48-51.)
There were no rail communication tunnels as at Hisai and the machines were moved in by hand.
Enlarging of tunnels Iiegan in March 194") and completion was planned for Septemhei-. Of a jilanned 4,500 employees and 640 machine tools, 725 employees and 271 machines were at work.
Handa was to produce ]iropeller parts. The plant was in operation but only a few parts had been finished.
53
y^-
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Q
UNDERGROUND PLANT LAYOL
1^
t>
D'
S3:
(o.
o
D
n
r
#
SCALE IN FE£T
US STRATEGIC BOMBING SURVEY
suMrroMO underground plant
AT
HANDA.TSU CITY
FIGURE 16
Photo No. 48. Interior at Handa.
Photo No. 49. Entrance at Handa. 55
Photo No. 50. Handa plant. Tunnels in sand mines near Tsu City.
Photo No. 51. Handa plant. (Note production tunnels opening into communications tunnel.)
56
TAKATSUKI
The Takatsiiki nii(l('ij>i-oiiiHl plant of the Kawa- saki Aii-cralt ("o. was located near Nai'iai village (III the outskirts of Takatsuki, which is midway between Osaka and Kyoto.
t)riginally intended for use as a central Army warehouse, these tunnels were begun in November IWi by the government. Their use by Kawasaki was not ordered until February 1945. A force of 3,500 Koreans living in the valley was engaged in the construction of this plant.
The tunnels, totaling a planned 300,000 square feet of floor area, were laid out in tw^o adjoining iiills, but only one area had reached any appre- ciable stage of completion (Fig. 17).
Tlie completed tunnel system was halfway up a roughly circular hill, 1,680 feet in height. Laid out in a grid network were 16 tunnels with 100,000 square feet of floor area and a planned machine tool capacity of 550. However, only six tunnels
were near production. Forty machine tools and electric power had been installed and production was to get under way on or about UO August 1945.
Mute evidence of the cessation of the war could be seen in the abandonment of machine tools poised over the edge of a cliff, preparatory to be- ing hauled into the tunnels. Steel plates were used as a base for sliding the tools into place in the tunnels.
At the time of inspection, 30 October 1945, the tunnels were fairly wet despite the fact that sev- eral of them were faced with concrete. Timber, expected to last for year and a half, was used in many places as shoring.
At a later date the company expected to install electric heating and ventilating.
This plant was constructed for the purpose of making parts for the Ha-140 inline engine for Tony II.
SETO
The Aiclii Aircraft Co. dispersed a part of its works to tlie hills north of Seto, a town about ten miles east of Nagoya.
A planned and completed floor area of 110,000 s(|uare feet was excavated in Ave areas, under five adjoining hills. However, only 45,000 square feet were in use.
The tunnels formed an irregular pattern (Fig. IS). They were fairly spacious but, in the usual fashion of underground plants were wet and
damp. Shoring was necessary throughout. (Photo- graphs 52-61.)
This plant was to make wings for Judy at first, and later, to make the entire airframe except for linal assembly.
It was planned to install 800 machine tools, of which about half were ready for use. Production was under way by 15 August 1945 but only a few wing spars were made.
57
58
I
Photo No. 52. Cave-in of machine shop at Seto.
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Photo No. 53. Entrance in spur of hill at Seto.
59
Plioto No. 54. Camouflaged entrance at Seto.
Photo No. 55. Entrance at Seto. 60
■"i/v '^^ •-,.■ S'.tN-
Photo No. 56. Entrance at Seto.
Photo No. 57. Surface building at Seto. 61
Photo No. 58. Seto plant. (Note extensive shoring.)
Photo No. 59. Seto plant. (The tight working quarters shown here were not uncommon.)
62
Photo No. 60. Interior at Seto.
Photo No. 61. Interior at Seto.
63
HIRO PLANT OF llTH NAVAL AIR DEPOT
Plans for underground production were made in April 1944. Construction and conversion of the tunnels were begun in November 1944. The first movement of equipment to the underground tunnel was in January 1945. The principal under- ground facilities were converted from a large undei'ground hangar which had been built in 1940, and an adjoining road tunnel. Actual production was begun in these tunnels at the end of January 1945. It was planned to move all the smaller ma- chines to these tunnels. One-half of the remaining large machines were to stay in the surface build- ings at Hire, while the other half were to be
moved to Takihara. This movement was to completed by June 1946. At the time of the ; raid on Hiro on 5 May 1945, over 90 percent the small and medium sized machines had alrea been moved underground. At the end of the v about 99 percent of the machines had been stalled in the underground plants.
In June 1945, the Hiro Navy Yard converted facilities for making marine engines to the maj facture of aircraft parts. Its machines were eluded in the underground dispersal. Plans these underground plants called for product: of 400 engines a month by April 1945.
UNDERGROUND PLANTS
Intelligence Check
Wiutime knowledge of Japanese underground installations was extremely meager. The Allies knew the locations of only three installations and nothing more. This was probably due to the fact that the underground program was not really begun until the last year of the war and there was not enough time for the information to seep out into Allied hands.
Anotlier cause was the difficulty of finding
underground tunnels through air photo inter| tation. Postwar photography and interpretati even when based on information supplied USSBS, was unable to find most of the entran at the locations that had been studied by USS And it was impossible to state how extensive- underground plant might be or what activity i being conducted in it.
The principal way of learning about un( grounds would seem to be by POW interrogati augmented by air photographs.
64
late irtl inal
CONCLUSIONS
"lie .Tiijianese underground installatious wei-e
nil too late for them to be able to save the pro-
liiiii of aircraft. In any event, their existence
111 not have overcome other problems such as
I la.ues of vital raw materials and fuel.
I instruction methods do not reveal anything
t is new or that is not already known to the
1 engineering profession. Only the profusion
iiiinels, caves, and mines is impressive.
iiherent dampness wreaked havoc with preci-
luachinery and with the health, morale and
iiy of workers. Air-conditioning and water
iuage were necessai-y for any long period of
.It ion, if machinery was to be protected
I list rust and corrosion and still be in use.
iildition, workers need to be fortified with an
mate diet. Workers also need plenty of light
luk by. Sun lamps would probably have been
licial to the workers.
nderground production probably suffered from lack of free and simple transport such as is i liable in a compact, well-planned surface fac-
Interdiction of highways and raili-oads leading to an underground retarded production by ob- structing the receipt of materials and tiie delivery of finished goods. Destruction of electiic power sources might have had the same effect.
The principal advantages of an underground in.stallation are that it is hard to find, makes a very poor target and would probably l)e safe from any weapon used in the second World War. Heavy gases would make an underground untenable but could be countered by air purification devices. Bacteria would be effective against workers whose vitality and resistance had been lowered by work- ing underground.
However, in spite of the disadvantages, it would seem advantageous for any nation to ]int some of its more vital production facilities into adequately prepared underground locations. If the Japanese had made an earlier start on their underground program their underground and dispersal plants might have constituted a more serious problem for the Allies.
65
UNITED STATES STRATEGIC BOMBING SURVEY LIST OF REPORTS
The following is a bibliography of reports i-esulting from the Survey's studies of the European and Pacific wars. Those reports marked with an asterisk (*) may be purchased from the Superintendent of Documents at the Government Printing Office, Washington, D. C.
European War OFFICE OF THE CHAIRMAN
•1 The United States Strategic Bombing Survey : Sum- mary Report (European War)
*2 The United States Strategic Bombing Survey : Over-all Report (European War)
*3 The Effects of Strategic Bombing on the German War Economy
AIRCRAFT DIVISION
(By Division and Branch)
*4 Aircraft Division Industry Report
5 Inspection Visits to Various Targets (Siiecial
Report )
Airframes Branch
6 Junkers Aircraft and Aero Engine Works, Dessau,
Germany
7 Erla Maschinenwerke GmbH, Heiterblick, Ger-
many S A T G Maschinenbau, G ni b H, Leipzig (Mockau),
Germany 9 Gothaer Waggonfabrik. A G, Gotha, Germany 10 Focke Wulf Aircraft Plant, Bremen, Germany
Over-all Roiwrt
11 Messerschmitt A G,
Augsburg, Germany
Part A Part B ApiK-ndices I, II, III
12 Dornier Works, Friedrichshafen & Munich, Ger-
many
13 Gerhard Fieseler Werke G m b H, Kassel, Germany
14 Wiener Xeustaedter Flugzeugwerke, Wiener Neu-
stadt, Austria
Aero Engines Branch
15 Bu.ssing XAG Flugmotorenwerke G m b H, Bruns-
wick, Germany 1<> Mittel-Deufsche Molorenwerke G ni li II. Taucha,
Germany IT Bavarian Motor Works Inc. Eisenach & Durrerhof,
Geimany
18 Bayerische Molorenwerke A G (BMW) Munich,
Germany
19 Henschel Flugmotorenwerke, Kas.sel, Germany
Light Metal Branch
20 Light Metals Industry (Part I, Ahnninnm
of Germany )Part II, Magnesium
21 Vereinigte Deutsche Metallwerke, Hildesheim, Gi
many
22 Metallgussgesellschaft G m b H, Leipzig, Genua
23 Aluminiumwerk G m b H, Plant No. 2. Bitterfe
Germany
24 Gebrueilcr (Jinlini G m b H, Ludwigshafen, 6'
many
25 Lnftschitfbau. Zeppelin G m b H, Friedrichshaf
on Bodeusee, Germany
26 Wieland Werke A G, Ulm, Germany
27 Rudolph Rautenbach Leichmetallgiessereien, Sol
gen, Gei-inany
28 Lippewerke Vereinigte Aluminiumwerke A
Lnnen. Germany
29 Vereinigte Deutsche Metallwerke, Heddernhei
Germany
30 Duerener Metallwerke A G, Duren Wittenau-Be^
& Waren. Germany
AREA STUDIES DIVISION
*31 Area Studies Division Report
32 A Detailed Study of the Effects of Area Bomb>
on Hamburg
33 A Detailed Study of the Effects of Area Bombi
on Wuppertal
34 A Detailed Study of the Effects of Area Bomb
on Dusseldorf
35 A Detailed Study of the Effects of Area Bomb:
on Solingen
36 A Detailed Study of the Effects of Area Bomb)
on Remscheid
37 A Detailed Study of the Effects of Area Bombi
on Darmstadt
38 A Detailed Study of the Effects of Area Bombi
on Lulieck
39 A Brief Study of the Effects of Area Bombing
Berlin, Augsburg, Bochum, Leipzig, Hagen, Do mund, Oberhausen, Schweinfurt, and Bremen i
CIVILIAN DEFENSE DIVISION
*40 Civilian Defen.se Division — Final Report
41 Cologne Field Rejwrt
42 Bona Field Report
43 Hanover Field Report
44 Hamburg Field Rei)ort— Vol I, Text; Vol
Exhibits
45 Bad Oldesloe Field Report
46 Augsburg Field Report
47 Keception Area in Bavaria, Germany
66
EQUIPMENT DIVISION
Electrical Branch
(icnuiiii lOU'ctricMl E(juipmoiit Industry Kcport Hrowii Boveri et Cie, Mannheim Kafertal, Germany
Optical and Precision Instrument Branch
iiptical and rrccisidii Iiislnnnont Industry Report
Abrasives Branch
The Gornuin Abrasive Industry
.Mayer and Schmidt, Offenbach on Main, Germany
Anti-Friction Branch
riie German Anti-Friction Bearings Industry
Machine Tools Branch
Maelune Tools & Machinery as Capital Equipment .Machine Tool Industry in Germany I [erman Kolb Co., Cologne, Germany I'ollet and Engelhard, Offenbach, Germany Xaxos Union, Frankfort on Main, Germany
MILITARY ANALYSIS DIVISION
I'lie Defeat of the German Air Force
\ Weapons (Crossbow) Campaign
Air Force Kate of Operation
Weather Factors in Combat Bombardment Opera- tions in the p]uroi)ean Theatre
I'.iinibing Accuracy, USAAF Heavy and Medium Bombers in the ETO
I icscription of RAF Bombing . The Impact of the Allied Air Effort on German Lo- gistics
MORALE DIVISION
iJ I he Kft'ects of Strategic Bombing on German Morale (Vol I & II)
Medical Branch
I i'lic Effect of Bombing on Health and Medical Care in Germany
MUNITIONS DIVISION
Heavy Industry Branch
11 i'lie Coking Industry Rejwrt on Germany i Inking Plant Reixtrt No. 1, Sections A, B, C, & D - liiitehoffnung.shuette, Oberhausen, Germany « Friedrich-Alfred Huette, Rheinhausen, Germany
0 Xeunkirchen Eisenwerke A G, Neunkirchen, Ger-
many
1 Ivfichswerke Hermann Goering A G, Hallendorf,
<Jermany
i August Thys.sen Huette A G. Ilamborn, Germany
'3 Friedrich Krupp A G, Borbeck Plant, Essen, Ger- many
I iKiitmund Hoerder Huettenverein, A G, Dortmund, • ierniany
•' Hiiesch A G, Dortmund, Germany
«|Bocliunier Verein fuer Giisstahlfabrikation A G, Bochum, Germany
Motor Vehicles and Tanks Branch
•77 German Motor Vehicles Industry Report *78 Tank Industry Report
79 Daimler Benz A (J, Unterturkheim, Germany
80 Renault Motor Vehicles Plant, Billancourt, Paris
81 Adam Opel, Russelheim, (iermany
82 Daimler Benz-Gaggenau Works, Gaggenau, Gei'-
ma ny
83 Maschinenfabrik Angsburg-Nurnberg, Nurnberg,
Germany
84 Auto Union A G, Chemnitz and Zwickau, Germany
85 Henschel & Sohn, Kassel, Germany
86 Maybach Motor Works, Friedrich.shafen, Germany
87 Voigtlander, Ma.schinenfabrik A (J, Plauen, Ger-
many
88 Volkswagenwerke, B''allersleben, Germany
89 Bussing NAG. Brunswick, Germany
90 Muehlenbau Industrie A G (Miag) Brunswick, Ger-
many
91 Friedrich Krupp Grusonwerke, Magdeburg, Ger-
many
Submarine Branch
92 German Submarine Industry Report
93 Maschinenfabrik Augsburg-Nurnberg A G, Augs-
burg, Germany
94 Blohm and Voss Shipyards, Hamburg, Germany
95 Deutschewerke A G, Kiel, Germany
96 Deutsche Schiff und Masehinenbau, Bremen, Ger-
many
97 Friedrich Krupp Germaniawerft, Kiel, Germany
98 Howaldtswerke A G, Hamburg, Germany
99 Submarine Assembly Shelter, Farge, Germany 100 Bremer Vulkan, Vegesack, Germany
Ordnance Branch
*101 Ordnance Industry Report
102 Friedrich Krupp Gruisonwerke A G Magdeburg,
Germany
103 Bochumer Verein fuer Gu.sstahlfabrikation A G,
Bochum, Germany
104 Henschel & Sohn, Kassel, Germany
105 Rheinmetall-Borsig, Dusseldorf, Germany
106 Hermann Goering Werke, Braunschweig, Hallen-
dorf, Germany
107 Hannoverische Masehinenbau, Hanover, Germany
108 Gu.sstahlfabrik Friedrich Krupp, Essen, Germany
OIL DIVISION
*109 Oil Division, Final Report
<110 Oil Division, Final Report, Appendix
*111 Powder, Explosives, Special Rockets and Jet Pro-
pellants. War Gases and Smoke Acid (Ministerial
Report #1)
112 Unilerground and Dispersal Plants in Greater Ger-
many
113 The German Oil Industry. Ministerial Report Team
78
114 Ministerial Report on Chemicals
Oil Branch
115 Ammoniakwerke Merseburg G ni b H, Leuna, Ger-
numy — 2 Appendices
67
110 Iii:iniiki)hle Benzin A G, Zeitz and Boblen, Ger- iiKiiiy, Wintersliall A G, Leiifzkendorf, Germany
117 Ludwigsliafen-Oiipini Works of I G Farbenindustrio A G, Ludwig.shafen, Germany
lis Ruhroel Hydrogenation Plant, Bottroi»-r.oy, Ger- many. Vol. I, Vol. II
119 Rhenanla Ossag Mincraloclwerke A G, Ilarlmrg
Refinery, Hamburg. Germany
120 Rhenauia Ossag Mineraloelwerke A G, Grasbrook
Refinery, Hamburg, Germany
121 Rhenania Ossag Mineraloelwerke A G, Willielms-
burg Refinery. Hamlinrg. Germany
122 Gewerkschaft Victor, Castrop-Rauxel, Germany,
Vol. I & Vol. II
123 Europaeische Tanklager nnil Transport A G, Ham-
burg, Germany
124 Ebano Asphalt Werke A G, Harburg Refinery,
Hamburg. Germany
125 Meerbeck Rbeinpreussen Synthetic Oil Plant — Vol.
I & Vol. II
Rubber Branch
12G Deutsche Dunlop Gummi Co., Hanau on Main. Germany
127 Continental Gumniinerke. Hanover, Germany
128 Huels Synthetic Rubber Plant
129 Ministerial Report on German Rubber Industry
Propellants Branch
Elcktrochemischewerke, Munich, Germany
Scboenebeck Explosive Plant, Lignose SprengstofC Werke GmbH, Bad Salzemen, Germany
Plants of Dynamit A G, Vormal, Alfred Nobel & Co, Troisdorf, Clausthal, Drnmmel and Dune- berg, German.v
Deut.scbe Sprcngcbemie G m b II, Kraiburg, Ger- many
OVERALL ECONOMIC EFFECTS DIVISION
V.U Over-all Economic Effects Division Report
1.30 131
132
133
Gross National Product Kriegseilberichte . Hermann Goering Works Food and Agriculture
134a Industrial Sales Output and Productivity
Special pai>ers which together comprise the above report
134b
133
136
137
138
139
140
141
142
143
144
14.J
140
PHYSICAL DAMAGE DIVISION
Physical Damage Division Report (ETO)
Villaconlilay Airdrome, Paris. France
Railroad Repair Yards, Malines. Belgium
Railroad Repair Yards, Louvain, Belgium
Railroad Ripair Yards, Hasselt, Belgium
Itailroad Repair Yards, Namur, Belgium
Suliniarinc Pens, Brest, France
Powder I'lant, Angouleme. France
Powder Plant, Bergerac, France
Coking Plants, Montigny & Liege, Belgium
Fort St. Blaise Verdun Group, Metz, France
Gnome et Rhone, Limoges, France
MIchelin Tire Factory, Clcrmont-Ferraiid, Franc
147 Gnome et Rhone Aero Engine Factory, Le Ma
France
148 Kugelfischer Bearing Ball Plant, EbeLsbach, G
many
149 Louis Breguet Aircraft Plant, Toulouse, France
150 S. N. C. A. S. E. Aircraft Plant, Toulouse, Fran 1.51 A. I. A. Aircraft Plant, Toulouse, France
152 V Weapons in London
153 City Area of Krefeld
1.54 Public Air Raid Shelters in Germany
1.55 Goldenberg Thermal Electric Power Station, Kb
sack, Germany 1.5C Brauweiler Tran.sformer & Switching Stat P.rauweiler, Germany
157 Storage Depot, Nahbollenbacli. Germany
158 Railway and Road Bridge. Bad Mnnster, Germ.
159 Railway Bridge, Eller, Germany IfiO Gustloff-Werke Weimar, Germany
Kil Ilenschel & Sohn G ni b H. Ka.s.sel. Germany
162 Area Survey at Pirmasens, Germany
163 Hanomag, Hanover, Germany
164 M A N Werke Augsburg. Augsburg, Germany
165 Friedrich Krupp A G, Essen, Germany
1116 Erla Mascliincnwerke. (i ni b H. Heitcrblick, ( many
167 A T G Maschinenbau G m b H, Mockau, Germ
168 Erla Maschinenwerke G m h H, Mockau, Germ
169 Bayerische Motorenwerke, Durrerhof, Germar
170 Mittel-Deutsche Motorenwerke G m 1) H, Taui
Germany
171 Submarine Pens Deut.sche-Werft, Hamburg, (
many
172 Multi-Storied Structures, Hamburg, Germany
173 Continental Gummiwerke, Hanover, Germany
174 Kassel Marshalling Yards, Kassel, Germany
175 Amnioniawerke, Merseburg, Leuna, Germany
176 Brown Boveri et Cie, Mannheim, Kafertal, '
m:iny
177 Adam Opel A G, Rnsselsheim, Germany
178 Dainder-Benz A. G, Interturkheim, Germany
179 ^'alentin Submarine Assendily, Fargc, German'
180 Volkswaggonwerke, Fallerslebeu, Germany
181 Railway Viaduct at Bielefeld, Germany
182 Ship Yards Howaldtswerke, Hamburg, Germai
183 Blolim and Voss Shipyards, Hamburg, German
184 Daimler-Benz A. G, Mannheim, Germany
185 Synthetic Oil I'lant. Mcerbeck-IIambui'g. Germt
186 Gewerk.schaft Victor, Castrop-Rauxel, German
187 Klockuer Humboldt Deutz, Ulm, Germany
188 Ruhroel Hy.drogenation Plant, Bottrop-Boy, (r
many
189 Neukirchen Eisenwerke A G, Neukirchen, Germ f
190 Railway Viaduct at Altenbecken, Germany
191 Railway Viaduct at Arnsburg, Germany
192 Denrag-Nerag Refineries, Misburg, Germany
193 Fire Raids on German Cities
194 I (i Farbenindustrie, Ludwigshafen, Germany. I
I & Vol II
195 Roundhouse in Marshalling Yard, Ulm, Genuiii 190 I G Farbenindustrie, Leverkusen. Germany
197 Chemische-Werke, Heuls, Germany
198 Grcndierg Marshalling Yard, Grenilierg, Germil'
199 Locomotive Sliups and P.ridges at Ilaiinn, Germi''
li.
li-
es
TRANSPORTATION DIVISION
I 'I'lic EllVcls of Sti-:ilryic I'.oinliiiiK uii (ici-many
'I'vausiKivtatidii ( i;.iil Operations Ovci- llif Itrcniicr I'ass I i:rr('cls of Bombing on Kailroad Insfallatioiis in Ito^'enslnng, Nurnljerg and Miniicli Divisions. German Locomotive Industry During the War German Military Ttailroad Tratlie
UTILITIES DIVISION
German Electric Utilities Industry Report
I to 10 in Vol I "Utilities Division Plant Reports"'
II to 20 in Vol II "Utilities Divisi(m Plant Re- ports"
'21 Klieiniselie-Westfalisclie Elektrizitaetswerk A G
Pacific War
OFFICE OF THE CHAIRMAN
Summary Report (Pacific War) Japan's Struggle to End The War The Effects of Atomic Bombs mi llirnsliima and Nagasaki
CIVILIAN STUDIES Civilian Defense Division
Field Report Covering Air Raid Protection and
Allied Subjects, Tokyo. Japan Field Report Covering Air Raid Protection and
Allied Subjects, Nagasaki, Japan Field Report Covering Air Raid Protection and
Allied Subjects, Kyoto, Japan Field Report Covering Air Raid Protection and
Allied Subjects, Kobe, Japan Field Report Covering Air Raid Protection and
Allied Subjects, Osaka, Japan Field Report Covering Air Raid Protection and
Allied Subjects, Hiroshima, Japan — No. 1 Summary Report Covering Air Raid I'rotection
and Allied Subjects in Japan Final Report Covering Air Raid Protection and
Allied Subjects in Japan
Medical Division
The Effects of Bombing on Health and Medical Services in .Japan
The Effects of Atomic Bombs on Health and Med- ical Services in Hiroshima and Nagasaki
Morale Division
The Effects of Strategic Bombing on Japanese rale
ECONOMIC STUDIES Aircraft Division
5 The Japanese Aircraft Industry 'J Mitsubishi Heavy Industries, Ltd. Corporation Report No. I
(Mitsubishi Jukogyo KK) (Airframes & Engines)
*17 Nakajima Aircraft Company, Lid. Corporation liepurt A'o. // (Nakajima Hikok KK) (Airframes & Engines) *18 Kawanishi Aircraft Company
i'orporation licjiort Ao. ///
(Kawanislii KokiiUi Kiibusblki Kaislia) (Airframes)
*19 Kawasaki Airei'aft Industries Company, Inc. C'orporaiio)! Hiport .\o. IV
(Kawasaki Kokuki Kogyo Kabushiki
Kaisha ) (Airframes & Engines)
*20 Aiclii Aircraft Comi)any
CorponitioH Report Xo. V (Aichi Kokuki KK) (Airframes & Engines)
*21 Sumitomo Metal Industries, Proijeller Divi-sion Corporation Report Xo. VI
(Sumitomo Kinzoku K(isyci KK, Pnropera
Seizosho) ( Propellers 1
*22 Hitachi Aircraft Company
Corporation Report Xo. VII (Hitachi Kokuki KK) (Airframes «& Engines)
Japan International Air Industries, Ltd. Corporation Report Xo. VIII
(Nippon Kokusai Koku Kogyo KK) (Airframes)
Japan Musical Instrument Manufacturing Com- pany
Corporation Report Xo. IX (Nippon Gakki Seizo KK) (Propellers)
*2."> Tacbikawa Aircraft Company Corporation Report Xo. X (Tacbikawa Hikoki KK) (Airframes) *2('i Fuji Airplane Company
Corporation Report Xo. XI (Fuji Hikoki KK) (Airframes I *27 Shdwa Airplane Company
Corporation Report Vo. XII
(Showa Hikoki Kogyo KK) (Airframes) *2S Lshikawajima Aircraft Industries Company, Ltd. Corporation Report No. XIII
(lshikawajima Koku Kogyo Kabushiki
(Kaisha) (Engines) *20 Nippon Airplane Company
Corporation Report Xo. XIV (Nippon Hikoki KK) (Airframes) *30 Kyushu Airplane Comiiany
Corporation Report No. XV (Kyushu Hikoki KK) (Airframes)
*2;^
*24
69
*31 Shoda Engineering Company
Corporation Rvvort No. XVI (Slioda Seisakujo) (Comiwneuts) •32 Mitaka Aircraft Inilustries Corporation Heport A'o
xrii
(Mitaka Kokvi Kngyo Kaluisliiki Kaislia) ( ('uuii)iinents) ♦33 Nissan Aiitonioliile Company
Corporation Rvport Xo. XVIII (Nissan Jidoslia KK ) (Engines) »34 Army Air Arsenal & Xavy Air Depots Corporation Report No. XIX (Airframes and Engines) *35 Underground Production of Japanese Aircraft Report Xo. XX
Basic Materials Division
•30 Coal and Metals in Japan's War Ecouomy
Capital Goods, Equipment and Construction Division
*37 The Japanese Construction Industry
*38 Japanese Electrical Equipment
*39 The Japanese Machine Building Industry
Electric Power Division
*40 The Electric Power Industry of Japan •41 The Electric Power Industry of Japan (Plant Re- ports)
Manpower, Food and Civilian Supplies Division
*42 The Japanese Wartime Standard of Living and Utilization of Manpower
Military Supplies Division
•43 Japanese War Production Industries
•44 Japanese Naval Ordnance
45 Japanese Army Ordnance
*46 Japanese Naval Shipbuilding
•47 Japanese Motor Vehicle Industry
•48 Jai>anese Merchant Shipbuilding
49 50 51
52
•53
Oil and Chemical Division
Chemicals in Japan's War
Chemicals in Japan's War — Appendix
Oil in Japan's War
Oil in Japan's War — Appendix
Over-all Economic Effects Division
The Effects of Strategic Bombing on Japan's War Economy (Including Appendix A: U. S. Eco- nomic Intelligence on Japan — Analysis and Com- IKirison; Appendix B: Gross National Product on Japan and Its Cunipononts; Appendix C: Statistical Sources).
Transportation Division
•M The War Against Japanese Transportation, 1941- 1945
60
Urban Areas Division
Effects of Air Attack on Japanese Urban Econ
(Summary Report) Effects of Air Attack on Ihban Complex To
Kawasaki-Yokohama Effects of Air Attack on the City of Nagoya Effects of Air Attack on Osaka-Kobe-Kyoto Effects of Air Attack on the City of Nagasaki Effects of Air Attack on the City of Hiroshim
MILITARY STUDIES Military Analysis Division
61 Air Forces Allied with the United States in
W^ar Against Japan
62 Japanese Air Power
63 Japanese Air Weapons and Tactics
64 The Effect of Air Action on Japanese Gr
Army Logistics
65 Employment of Forces Under the South
I'acitic Command
06 The Strategic Air Ol>erations of Very H
Bombardment in the War Against J (Twentieth Air Force)
07 Air Operations in China, Burma, India— "V
War II OS The Air Transport Command in the War Ag
Japan 09 The Thirteenth Air Force in the War Ag
Japan
70 The Seventh and Eleventh Air Forces in the
Against Japan
71 The Fifth Air Force in the War Against Japi
Naval Analysis Division
*72 The Interrogations of Japanese Officials (V'
and II) *73 Campaigns of the Pacific War *74 The Reduction of Wake Island *75 The Allied Campaign Against Rabaul 76 The American Campaign Against Wotje, 1
lap, Mille, and Jaluit (Vols. I, II and III) *77 The Reduction of Truk
78 The Offensive Mine Laying Campaign Af
Japan
79 Reiwrt of Ships Bombardment Survey Pa
Foreword, Introduction, Conclusions, and eral Summary
80 Report of Ships Bombardment Survey Party
closure A), Kamaishi Area
81 Reiwrt of Ships Bombardment Survey Party 5l
closure B), Hamamatsu Area
82 Report of Ships Bombardment Survey Party 5)
closure C), Hitachi Area
83 Report of Ships Bombardment Survey Partj
closure D), Hakodate Area
84 Report of Ships Bombardment Survey rart.\
closure E), Muroran Area
85 Report of Ships Bombardment Survey Parlj
closure F), Shimizu Area
86 Report of Ships Bombardment Survey Party '"'
closures G and II), Shionomi-Saki and NoM Saki Areas
70
IJipori (it' Ships I!oiMli:ir(liiii'iil Survey I'lirly (Kii- iliiMiri' I I, ( '(Uiiinc'iils ;iii(l l):il:i on Kft'i'ctivciiess
nl' AllllllUIlitidll
1;^ port (if Ships Bdiiiliardiiiciil Siii'vcy I'afty (Eii-
( IdSiire .1). ('(iiiiinciils Mild Unta (in Accuracy of
I'ii'iii:;- Kipdi-ts (if Ships P.oiiilianliiK'iit Survey I'arty (Eii-
I Insure K), lOffects (if Surface Kdiiiliariliiii'iits on
.la]>aiiese War I'oleiitial
Physical Damage Division
Kffect of llie Incendiary Bonili Atta(ks on Japan (a Heiiort on Eight Cities I
The EfftH-t.s of the Ten Thousan<l I'ouud Homb on .Tapanese Targets (a lieixirt on Nine Incidents)
Effects of the Atomic I'.onili on Ilirdshinia, Japan
Kffects of the Atomic Bomh on Nagasaki, Japan
Effects of the Four Thousand round Bomii (ni Japanese Targets (a Keiiort on Five Incidents)
Effects of Two Thousand, One Thousand, and Five Hundred Pound Bombs on Japnne.se Targets (a Iteport on Eight Incidents)
i. Itejiort on Ph.vsical Damage in J.ipan (Sum- mary I!ei>ort)
G-2 Division
lapanese Military and Naval Intelligence
|
!>.S |
Evalnalidii |
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.lai>a nese |
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liiiii |
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ill) |
Ev.-ilnalioH |
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Japanese |
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I (Id |
Evaluation |
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.Faiianese |
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/'loltiiii/ |
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101 |
Evaluation |
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Jajianese |
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tlljl-sis |
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l(t2 |
Evaluatidii |
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Japanese |
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](« |
Ev;iluation |
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.T.-ijianese |
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1(14 |
Evaluation |
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Jai)anese |
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Kl.'i |
Evaluation |
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Japanese |
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Hciicc |
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km; |
Evaluation |
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Japanese |
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1(17 |
Evaluation |
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Jaiianese |
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roads |
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108 |
Evaluation |
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Japanese |
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(llll-lif; |
(it I'lioldgr.ipliic Intelligence in the Ildirielaiid. I'arl I, lidiiiiinlirniivi; Re- nt' I'hdlograiiliic liitelligenoe in the Homeland, Pari II. .Mr/ifUls of Photographic Iiitelligetice in the Homeland. Pari III, Cdinpiitcil Homli
of Photographic Intelligence in the Homeland. I'.-irt I\', irhaii Arc<t An-
of Phdlographic Intelligeneo in the Homeland, Pail V, Ciimoufliiiic of I'hotographic Intelligence in the Homeland, Part VI, Shiiiiihitj of Photograpinc Intelligence in the Homeland, I'art VII, J'JIeclrfjiiif.t of Photographic Intelligence in the Homeland, Part VIII, Jliiich lutrlli-
of Photogiai)hic Intelligence in the Homeland, Part IX, Artillery of Photographic Intelligence in the Homeland, Part X, Roads and Rail-
of Phot(jgraphic Intelligence in the Homeland, Part XI, Industrial An-
■V-U. S. GOVERNMENT PRINTING OFFICE: 1947 714387
71
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THE UNITED STATES STRATEGIC BOMBING SURVEY
Coals and Metals
IN
JAPAN'S War Economy
Basic Materials Division
Apra 1947
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