34895017 defense installations on iwo jima usa 1945

8/3/2019 34895017 Defense Installations on Iwo Jima USA 1945

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EFENSE INSTALLATIOON IWO JIMA

Classification ch*ng*d toED

Maj., Inf.Custodian

CINCPAC-GINCPOABULLETIN NQ. 136-4510 JUNE 19458 JUN1945


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Defense Installationson

I WO JIMAflaintly

CINCPAC-CINCPOAFLEET MARINE FORCE

V AM PHIBIOUS CORPS3rd, 4th & 5 th MARINE DIVISIONS

JICPOA L" 5 0 6 0 7 - 23 THRU 144


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UNITED STATES PACIFIC FLEETAND PACIFIC OCEAN AREASMCH/cc HEADQUARTERS OF THE COMMANDER IN CHIEF

10 June 1945 - Serial DIS-1OO93OFrom:To:Subject:Enclosure:

1.

Commander in Chief, U. S. Pacific Fleet and Pacific Ocean Areas.Distribution List.CINCPAC-CINCPOA BULLETIN No. 136-45.Defense Installations on Iwo Jima.(A) Subject bulletin.Enclosure (A ), forwarded herewith, need not be reported and when no. _

longer of value should be destroyed. No report of destruction is necessary.

M. LBpENDRE,By direction.Copies ARMY5 ComGenAAASch Ft Bliss Tex2 CO AMS War Dept5 Chief of. Engrs War Dept

5 Chief of Ord War Dept2 Chief Sig Off War Dept5 ComdtCASch Ft Monroe Va2 ComdtCom&GenStaffSchFt Leavenworth Kan12 ComGenAAF War Dept2 DirJointTargetGroup AAFPentagon Bldg Wash DC12 ComGenAGF War Dept2 ComGen2ndAF Colorado Springs Colo2 ComGen4thAF SF Calif2 ComGenWesDefCom Presidio SF Calif2 CO AeroChartServAAF War Dept2 CO OrdBDCAberdeenProvingGroundAberdeen Md2 ComGenAAFSATAAFTAC Orlando Fla14 MISReadingPanel War Dept2 OPD War Dept1 ChiefPACMIRS Camp Ritchie Md1 CO AimyUnitWestCoast PO Box 651Tracy Calif3 ComGenSEAC APO 432 NY3 BGS(I)MainHqALFSEA APO 432 NY1 CO CPICAirComSEA New. elhi India2 ComEasternAirComSEA APO 671 NY2 DMIGHQ New Delhi India2 ComGenUSAF APO 885 NY1 ComAirComSEA New Delhi India1 SuptSEATIC APO 885 NY14 ComGenUSAFCTO APO 879 NY2 ComGenl4thAF APO 627 NY2 OinCSINTIC APO 879 NY2 ComGenllthAF APO 980 Seattle Wash4 ComGenAdvCPAlaskan Dept APO 980

Seattle Wash2 ComGenNZAHq Wellington NZ15 ComGenPOA APO 9582 CO 30thEngrBaseTopoBn APO 9572 CO 64thEngrBaseTopoBn APO 246200 ComGenAAFPOA APO 95320 COEGHQSWPA APO 50010 ComGenUSAFFE APO 50110 ComGenUSASOS APO 7072 DirNEFIS APO 5002 DirADVANEFIS APO 92650 CinCGHQSWPA APO 50012 ComGenASF War Dept

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10 June 1945 Serial DIS-1OO93O

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33111

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OinCPICNYd WashCO NavResLab BeliefOinCTAIC NAS Anacostia DCComAirPac2 ComNorPac2 ComSoPac2 MEIU#1 FPO SF2 MEIU#4 FPO SF1 ComBatRonTWO1 ComBatDivTWO2 ea ComBatDiv1 ea CO BB2 ComCruDesPao1 ea ComCruDiv1 ea CO CA CB CL1 ea ComTaskFlot1 ea ComDesRon1 ea ComDesDiv1 ea ComCortDiv1 ea CO DD1 ea CO DE PF3 Com3rdFleet3 Com5thFleet3 Com7thFleet1 Coml41 DIO 14ND45 CO SEFIC5 OinCAlCCinCPOAAdvHq1 OinCAlCNorPac100 OinCJDU Navy 943100 OinCJDU Navy 30111 AtCom Navy 32331 ea NavylsCom1 ea CO NavAdvBase1 ea ComNavBase1 CO NAS Seattle Wash1 ComdtNOB Navy 32561 ea ComNOB4 AdCominPac2 ea ComMTBRonPac2 ComMTBRonsSWPA2 ea ComSeaFronPac2 ComServPac1 ea ComServRonPacComNavy 3233 2 DirAdBaseComServPacComNavForces Navy 3256 5 CO InterpRonONE Navy 3256ComSubArea Navy 3254 5 CO InterpRonTWO FPO SFRepComDesPacCentPacFwd

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Table of ContentsJAPANESE DEFENSIVE PLAN AT IWO JIMA . . . . . 2-6ILLUSTRATIONS . . 7-119General Terrain Features 7-16Beaches . . . . . . . . . 7-10Terrain Inland * , 11-16Obstacles and Mines 17-20Mines 17-18Trip Wire 19Anti-Tank Ditches 20Caves 21-25Coast Defense - Artillery 26-3915 cm CD Guns 26-2614 cm CD Guns 29-3112 cm CD Guns 32-3312 cm (Short) Naval Guns 34-378 cm CD Guns 38-39

Antiaircraft and Dual Purpose Batteries 39-6412 cm DP Guns 39-4210 cm DP Guns 43-457 cm AA Guns 46-4825 mm AA MG 49-5813 mm MG 59-60Searchlights . . . . . . . . 61-64Blockhouses 65-70Covered Artillery Emplacements 71-86120 mm Howitzers 71-7475 mm (Type 38) Field Guns 75-7875 mm (Type 90) Field Guns 78-8047 mm Ant i-Tank Guns 8I-8537 mm Anti-Tank Guns 86Open Artillery Emplacements 87-8847 mm Anti-Tank Guns 8737 am Anti-Tank Guns 88Mortars 89-95320 mm Spigot Mortars . 89150 mm Mortars 90-9281 mm Mortars 93-94Grenade Launchers . 95Rockets 96-IOO200 mm Rocket Launcher 96-98250 kg Rocket Launcher 9963 kg Rocket Launcher 100Pillboxes 101-103Rifle Pits 104-105Tanks 106-108Dummies 109-111Radar and Radio Station 112Revetted Vehicles 113

Air Raid Shelters . . . . . . . 114-115Ammunition Storage '. 116-117Miscellaneous . . . . . . . 118-119MAP APPENDIXEnemy Defense Installations as observed from ground study.Arcs of Fire for Casemated Coastal Defense Guns on Iwo Jima.Anti-Aircraft Defenses.Blockhouses with principal directions of fire indicated.Covered Artillery with principal directions of fire indicated.


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Japanese Defensive Plan At Iwo JimaThe strategic importance of IWO JIMA. need hardly be emphasized. Its value asan airbase midway between the MARIANAS and the heart of JAPAN has already beenproved. After the occupation of SAIPAN, the Japs must have known that IWO would beattacked* The only question was VHEH. The story of their haste in constructingdefenses is told in aerial photographs from 15 June 1944 until D-Day, 19 February

1945.

INCREASE OF FORTIFICATIONSAt the time SAIPAN was invaded, only AA defenses, hasty fire trenches, and preliminary beach defenses had been prepared at IWO JIMA, By September 1944* positionshad been constructed in depth behind the beaches. Company and platoon positionswere then in evidence, and concrete pillboxes and covered artillery emplacementswere under construction. By December, most beach positions were completed and hadbeen strengthened by the construction of heavy concrete blockhouses. A cross-islanddefense line in depth protecting the northern part of the island was springing upalong the high ground north of Airfield No . 1. Additional AA defenses, increasednumbers of covered artillery and coast defense guns, and more and more concretepositions and minefields on the beaches were noted on each succeeding photographiosoftie. By D-Day, key positions had been connected with pillboxes and were protectedby covering fire from artillery, anti-tank guns, and mortars, previously sighted in.Intelligence prior to the invasion of IWO indicated a formidable garrison forcewith many major caliber weapons and extensive tank and personnel obstacles; however,aerial photographs and maps gave only a limited picture of one of the enemy*s bestdefensive weapons, the terrain. An amphibious assault in force was limited to theeast and west beaches of the narrow southern part of the island. These conditionsgave the Japs an advantage in preparing defensive positions for all-around security.Only small groups were needed to cover very narrow beaches with steep exits alongthe northern coast.

COVER AND DISPERSAL, Captured documents, confirmed by ground study, indicate the enemy's battlestrength was conserved by countermeasures against shelling and bombing. The terrainwas well suited for cover, and caves were so numerous in some sections of the island

that it was impossible to plot them all on a 1:10,000 map. The coarse, loose, volcanic ash kept damage from shell fragmentation to a minimum. Ammunition, stores,and personnel were dispersed in caves and behind protective terrain where navalgunfire and artillery could not reach them.CAMOUFLAGE

Camouflage encountered and camouflage discipline during construction, as evaluated from aerial photographs, was excellent. Positions were at all times coveredwith materials which blended into the surrounding terrain and vegetation. Spoilfrom excavations was planted with grass to obliterate traces of military activity.Natural vegetation was used to a large extent to conceal well-built positions fromaerial attack. While such practices could not always elude photographic interpretation, nevertheless many positions were not detected until gun fire had blown awaythe concealing vegetation. Maximum use was made of IW0*s sparse growth for concealing trenches, rifle pits, machine gun and artillery emplacements. Positions aslarge as those housing 120 mm Howitzers were undetected under the protective coveringof trees in their natural state.COAST DEFENSE

Coast defense artillery ranging from 4.7" (120 mm) to 6M (I55 mm) guns wasinitially effective against our ships. All CD guns were casemated in four to sixfeet of reinforced concrete. Each emplacement was so positioned in the terrain that


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it was normally protected from naval gunfire. A ship taking a CD gun under directfire necessarily exposed itself to the gun at which it was firing. Many guns wereso camouflaged that their location was unknown, until they opened fire.ANTIAIRCRAFT

Antiaircraft batteries were numerous, including 120 mm DP, 100 mm, 75 mm, and25 mm in triple, twin, and single mounts. The Japs could not satisfactorily concealthese weapons, but their continued use against aircraft and our personnel ashoretestifies to the sound construction of their emplacements.EAST BEACH POSITION

The elaborate trench system facing the eastern beaches had been entirelyabandoned. The loose nature of the sand suggests their presence as dummies, al though they may have been prepared originally as hasty beach defenses before adequateconcrete positions were built. Well-constructed blockhouses encasing 25 mm machinecannons to 120 mm short naval guns were the first defenses encountered on and nearthe beach. Some concrete pillboxes and sandstone revetted rifle pits gave infantryprotection to the heavier weapons. The ground at the base of Airfield No. 1 wasmore suitable for dug in positions, and most of the infantry positions protectingthe east beach were here. The positions were not so much the target for naval gunfire, and excellent observation and good fields of fire were afforded here. Theposition of Airfield No. 1 limited the depth of these positions to approximately500 to 700 yards. Supporting fires were delivered from the flanks using the observation provided by Mt. SUHIBACHI and the high ground over the East Boat Basinand around Airfield No. 2. The area between the beach and Airfield No. 1 was steepand impossible for wheeled vehicles* to traverse. Movement of infantrymen and tankswas impeded by the loose soil with the result that they offered excellent targetsto anti-tank and anti-personnel guns and tactics.WEST BEACH POSITIONS.

The defenses of the West Beaches were probably more extensive and elaboratethan East Beach defenses.' Airfield No. 1 permitted these defenses to be 700 to 1400yards deep giving considerably longer fields of fire and permitting a more elaboratesystem of dummy positions fronting the actual main positions and designed to drawour preliminary bombardment. The terrain was much more substantial for caves andunderground shelters, and positions were better protected from our naval gunfire.SURIBACHI POSITIONS

In the south a cross-island defense line was constructed on the terraced slopeswhich guarded the approaches to Mt. SURIBACHI. It consisted of a maze of concretepillboxes, bunkers, shelters, and blockhouses which were capable of all-around defense and were mutually supporting. In addition to this elaborate surface organization, there was an equally elaborate subsurface organization of shelter, passageway, living quarters, storage areas, and cave-type firing positions which providedadequate protection against the heaviest of bombs and shells. The excellent observation from the heights of SURIBACHI and the high ground around Airfield No. 2were the feey to controlled artillery and mortar fire,MAIN DEFENSE BELT

Since landings in strength were limited to the east and west beaches near thesouthern end of the island, the enemy prepared his main defense in depth in a cross-island belt. Beginning in the west at the rocky cliffs to the north of the westernbeaches, it stretched east across the island to skirt the southern end of AirfieldNo. 2, and terminated in the cliffs which form at the northern end of the easternbeaches. The center of this belt was 2600 yards deep. It gained its strength fromits depth and its concrete and steel structures, positioned so as to obtain longfields of fire which were carefully calculated and tied into the overall defensesystem. Reliance on caves as a shelter and a fighting position was increas'ed here.


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Most of the positions showed excellent engineering and terrain appreciation. Communications were maintained by trenched wire, radios, and a labyrinth of undergroundtunnels connecting all areas. One of these tunnels was explored for 800 yards,and 14 entrances were found; it housed two battalion command posts and was equippedwith lights and telephones. Artillery, including heavy mortars and rockets in andbehind this defense belt, could cover most of the beach area. Positions were provided with complete preregistration data.Strong points were established around commanding ground, Conorete-faced cavesand infantry positions in the erosion-made crevices were frequently so close to

gether that an equally strong defensive position existed only a few yards to therear or flank. Contact became so close that safety of our own troops prevented useof artillery, naval gunfire, or air support in reducing these positions. One bluff,forming something similar to an amphitheatre, contained two terraces and three tiersof concrete pillboxes and oaves*FINAL DEFENSIVE AREA '

North of this cross-island defensive sector, the extremely rough terrain fromthe coast to 2000 yards inland created a natural defensive area. The number ofcaves and terrain characteristics somewhat compensated for the reduced amounts ofconcrete and steel. These features, coupled with the masses of men employed, tendedto make this final defensive area equally as strong as the main defensive positions.In attacking these positions no Japs were to be seen, all being in caves or crevicesin the rocks and so dispersed as to give an all-around interlocking defense to eachsmall compartment. Attacking troops frequently were subjected to fire from flanksand rear more than from their front. It was always very difficult and frequentlyimpossible to locate exactly where defensive fires originated.

In defending IW0 JIMA, the Japs employed one basic tactic which in a sense wasa departure from the Japanese defensive operations hitherto generally encountered.This tactic was simply to occupy previously determined D-Day positions and maintainthem, without recourse either to costly rtmain effort" counterattacks or organizedwithdrawals. This plan was not only simple in conception but in general was skillfully executed and well adapted to the terrain of IW0 JIMA. There were no organizedattempts made to counterattack our beachhead, no large scale night counterattacks,no "all-out" banzai charge. Instead, the enemy committed a minimum number of troopsto the southern beach area and defended it by delivering heavy volumes of fire fromboth SUHIBACHI and the north so that even when the southern area was finally taken,the bulk of the enemy's forces remained intact and were well entrenched in the mostheavily fortified part of the island. The enemy, by continuing to follow his simplebut basic defensive tactic of occupying a position and refusing to yield until dugout and killed without counterattacking and without withdrawing, was able to maintain organized resistance for over twenty days. There were no tactical withdrawals,no retrograde or delaying actions in the military sense, though in some instancesisolated withdrawals were made to preserve units and individuals threatened withinevitable destruction. It is now known that this defense of holding to the endwithout counterattack or withdrawal was the express plan conceived by the CommandingGeneral. It was this simple tactic, coupled with the incredible rocky terrain andthe maximum use the enemy had made of this terrain in constructing fortified positions which made the capture of IW0 JIMA so difficult*ANTI-TANK TACTICS

Captured battle plans indicate the enemy's fear of our tanks. Mine fields,magnetic mines, and explosives carried by hand were employed at the beach where theloose sand seriously impeded the movement of even full-tracked vehicles. Anti-tankguns, mainly the high velocity 75 mm and 47 mm, were the principal weapons employedinland. Many anti-tank guns had one or more supplementary or alternate positions*These weapons were sited in terrain affording fields of fire covering possible tankroutes from the beach; however, considerable emphasis appears to have been placed onlocating an emplacement where it was protected by an abutting bluff or terrace, whicshielded it from frontal flat trajectory fire.


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BLOCKHOUSES AND PILLBOXESBlockhouses and pillboxes near the beaches on the more open terrain were almostinvariably sited for flanking fire. Wherever possible, a pillbox was behind a naturalmound of sand. It often had only a small fire port which allowed approximately 30of traverse; however, there was a sufficient number of mutually supporting pillboxesto offset the restricted field of fire of each weapon.Many blockhouses near the beach had sand piled as high as 50 feet in front of

them. A narrow fire lane through the sand revealed the direction of fire, but manypositions were so well protected that they were still firing until reduced by infantry. Pillboxes were protected similarly; infantry commanders often found itnecessary to request main battery fire from naval vessels when secondary batteryfire could not blast the sand from in front of well built positions.OF TANKS

Relatively few tanks, medium and light, were present on IWO JIMA. The roughterrain, size of the island, and fixed nature of defenses probably account for thelimited number. Their manner of employment was as an anti-tank weapon. They wereused in support of the main cross-island defense belt either in a revetment or behind protective terrain, camouflaged and stationary. Their 37 mm, 47 mm, and 57 mmguns fired anti-tank and personnel missions like the many 47 mm guns. Reports indicate small tank units were to be employed to support local counterattacks. Thereis little evidence they were so used. The torn up condition of roads and constantartillery fire may well have prevented any movement.ARTILLERY

Artillery tactics were characterized by good observation and careful preplanningof fires. Range stakes were found in the vicinity of landing beaches. The elaboratecasemated structures in which artillery pieces were housed, the cave positions fromwhich mortars and rockets were fired, operated to limit the number of pieces whichcould be brought to bear on a single area. Despite perfect observation, artillery,rocket, and mortar fires were never massed against us in the same manner in whichwe mass artillery fires. Dual purpose guns were used to fire time fire over ourtroops*An artillery group gave coordination to all field artillery and mortar employment; coast defense and AA artillery were not included in this command. Mortarshad the primary mission of filling in the gaps between the fires of the other guns,but after the land fighting stage was reached they shifted to control of sectorinfantry commanders.The principal locations of mobile artillery were in the higher ground north ofAirfield No. 2 with forward OPs in prominent elevations along the main defensivebelt. There definitely were more weapons at the disposal of commanders than wereorganically assigned to the units. The fixed nature of the defenses permittedpersonnel normally used for ammunition carriers and for the movement of mobileweapons to be employed to man additional weapons added to basic tables of organization.

MORTARS AND ROCKETSAlthough approximately twelve 320 mm spigot mortars were encountered on theisland, their effectiveness is doubtful. Emplacements were well constructed andconcealed but only a few rounds were fired. IWO's terrain was suited for the useof the many 150 mm, 81 mm and smaller mortars found there. Ammunition was storedthroughout the northern half of the island in caves and hasty firing positionswere utilized at the entrances. The 150 mm mortars were used to fire on landingbeaches. These weapons and the smaller mortars were withdrawn as the situationdemanded.


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Three types of rockets were used as artillery weapons. Several positions weresighted for firing at ships approaching close to shore. The V-trough launcher wasused for 63 kg and 250 kg aerial bombs with rocket motors providing the propellingforce. A 200 mm rocket was used from a mobile-type launcher and a launcher which ismounted on a mortar-type bipod. Rockets were dispersed in deep draws over the northern portion of the island and the launchers could be moved to the site of the ammunition.

* * * * * * * * *

It is evident that little was left undone by the Japs in constructing as formidable ground defenses as possible on an island with the size and particular terrainof IWO JIMA. A study of Japanese defense installations encountered in the field ispresented with photographs and drawings on the following pages.


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4B C D E AMAP APPENDIXCINCPAC-CINCPOA BULLETIN NO. 1

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- A I B C : D E + A MAP APPENDIXCINCPAC-CINCPOA BULLETIN NO 13

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THE SPECIAL GRD SYSTEM IS SUPERIMPOSED ONTHIS MAP N PURPLECOLOR THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ONTHISMAP IN SALMON WITH BLUE LETTERS ANDNUMBERS. THIS SYSTEM IS TO BEUSED FOR AREA DESIGNATIONS.THE NUMBERING OF THE 1000-YARD TARGET AREAS AND LETTERINGOF THE EOO-YARO TARGET SQUARES HAS NO RELATION TO THE NUMBERINGUSED IN THE GRID SYSTEM.

PIN-POINT DESIGNATION OF R J I 0 6 IS BC 7 5 0 - 7 0 9R J I 0 6 IS IN TARGET SQUARE 132 A

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BLOCKHOUSESWITH PRINCIPAL DIRECTIONS OF FIRE INDICATED


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h + 1 h I V 1B . C D A B C D EMAP APPENDIXCINCPAC-CINCPOA BULLETIN NO

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R S : TTHE SPECIAL GRD SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLECOLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THISMAP IN SALMON WITH BLUE LETTE RS AND NUMBERS . THIS SYSTEM IS TO BETHE NUMBERING OF THE IOOO-YARD TARGET AREAS AND LETTERINGOF THE 200-YARO TARGET SQUARES HAS NO RELATION TO THE NUMBERINGUSED IN THE GRID SYSTEM.

PIN-POINT DESIGNATION OF RJIO6 IS BC 750- 70 9R J I 0 6 IS IN TARGET SQUARE 132 A

ANTI-AIRCRAFT DEFENSES

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ItIIIIIIA B C D A B [ C j D EMAP APPENDIXCINCPAC-CINCPOA BULLETIN NO. 13

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WO JIMA

THE SPECIAL GRD SYSTEM IS SUPERIMPOSED ON THIS MAP IN PURPLECOLOR. THIS SYSTEM IS TO BE USED FOR PIN POINT DESIGNATIONS.

THE ARBITRARY TARGET SQUARE SYSTEM IS SUPERIMPOSED ON THISMAP IN SALMON WITH BLUE LE TTER S AND NUMBERS THIS SYSTEM IS TO BEUSED FOR AREA DESIGNATIONS.

THE NUMBERING OF THE IOOO-YARD TARGET AREAS AND LE TTERINGOF THE 200- YARD TARGET SQUARES HAS NO RELATION TO THE NUMBERINGUSED INTHE GRID SYSTEM.

U ! V W ;X PIN-POINT DESIGNATION OF RJIO6 ISBC 7 5 0 - 7 0 9R J I 0 6 IS IN TARGET SQUARE I32 AB C D A B C D

COVERED ARTILLERYWITH PRINCIPAL DIRECTIONS OF FIRE INDICATED

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V W X U V W X A L T E R N A T E P O S I T I O NHT SUPPLEMENTA RY POSITIONE - A B C DJ -F


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' T 17' IS1 I4I2O'

CONFIDENTIALMAP APPENDIXCINCPAC-CINCPOA BULLETIN NO 136-45

ARCS OF FIRE FOR CASEMATEDCOASTAL DEFENSE GUNSONIWO JIMA

PLOTTED FROM GROUND STUDY AND CAPTURED MA P

195


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Cleared of mines, . t theshoulders andof road is still mined Extent of field not > nownflints are. 3"*"'tf6 s//Us iv/ vc/sficM r) 6 mines removed 252 253ingle nbrn nem ispnencaiarid bombs reported in Underermine mines Box,area. 3-/0-45 stick mines Shape charge(I) STjck qrenadetz) s' Duds,1 nest Tieiqsconrained a (i) &UA minesand (21) Taoe-Measure // were removedpe-neat vreSee Insert '/f- B~- C HIRAIWA BUY uop bomb disper \al area (65 to 70)area (-9B) bombs 250 Kg dispersei 1 in groups of S.id 0 on each side groups IS ft. opaeasur&4 ydstich. mines (I) ROW 2 /7( rn mines250 kg bombs iv ydstick !3) Rows / Hi rn /nrnesmines ? rows removed. /orf. her we en rows411 removed.This field consisted of 4 roparallel o the beach or iThe mines were 63kg


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GENERAL TERRAIN FEATURES -Beo che s

Amphibious tractor stuck Iloose sand on East Beach.

Deep footprints indicateloose character of sandon beaches.


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Beaches

Marston matting on EastBeach essential tovehicular movement overthe soft sand.

Bogged down Jeep withchains on East Beachsubsequently damagedby enemy fire.

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Beaches

Wave-cut terrace on EastBeach.

Terrace on East Beach andamphibious tractor.


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Beaches

Steep gradient of beach combined with looseness of sanmade movement difficult forvehicles and troops.

View of terrace Just inlandfrom Blue Beach #2.

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Terrain Inland

Looking west . This Is atypical area inland alongthe West Beach. (TA-163J )

Clumps of vegetation inthe central areas concealed trenche s, riflepits and MG positions.


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Terrain Inland

Covered artillery position housing 47 mm ATgun firing down runwayof #2 airfi eld. Typeof terrain in which gunemplacements were leastvulnerable to naval gunfire. (TA-183C)

Areas of this sort provided excellent cover tothe enemy in his a ttem ptsto infiltrate our lines.(TA-E33M)

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Terrain Inland

Approaching Hill 362 showing the natural ruggedterrain which confrontedtroops. Since troopscould advance here onlywith great difficulty,this terrain was a decidedasset to the enemy.(TA-216N)

Looking, wes t from thi:area showing sparsevegetation. (TA-216A)

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Terrain Inland

m

Looking south showing therugged terrain approaching Mt. Suribachi.(TA-132R)

This picture is typicalof cave-infested n ort hern area terrain.(TA-234D)

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Terrain Inland

Rocky outcrops and scrubvegetation characteristicof the northern one-thirdof the island making mo vement of troops difficult.

Rocky terrain near northcoast provided the enemywith natural positionsfor MGs and riflemen.

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Terrain Inland

- *

View of terrain typicalof that encountered Invicinity of Hill 382.(TA-200Y)

Trench cut through reckleading to gun positionsnear East Boat Basin.(TA-166D)

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OBSTACLES AND M I N E S Mines

Close-up of taried oildrum with the top cutopen and ready for land-mine to be emplaced.Due to the enemy's disrupted schedule causedby cur bombing prior toD day, they did not havetime to set up the minefield in conjunctionwith the oil dru ms.(TA-180X)

View of West Beach showing55-gallon oil drums whichwere to be used as landmines. Electrically controlled mines were to beput into the drums to hinder our landing on thisbeach

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Mines

250 kg bomb burled insand as land mine.These mines were fuzedwith yardstick minesPlaced on top of thebomb and secured inPlace with fine wire .Many such mines thusemployed were locatedstrategically, andwell covered with firefrom AT weapon s.(TA-165 0)

View of the West Beachshowing one-horned conical land min es. Theentire West Beach wasmined.

18


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Trip Wire

Trip Wire. (TA-201S)

This was the only evi denceof trip wire or barbed wirebeing used in this area.It proved ineffectiv e Instopping troops from landing or advancing.(TA-148H)(looking east)


30/130

Anti-Tank Ditches

View of AT trench,(TA-198H)

View of AT trench,(TA-198H)

20


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CAVES

Interior view of cave.This cave had a seriesof caves leading offin differen t directionsand connecting withother caves In the nearvicinity. Food, ammunitio n and .clothingwere found In thesecaves indicating troopshad been quarteredthere. (TA-199U)

Interior view showingsteps leading out of thecave whi ch is about fortyfeet under ground withlarge rooms throughoutfor the quartering oftroops. (TA-199U)

2


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Caves

Typical entrance to extensive cave network,extending from underneath the quarry nearthe East Boat Basinwith tunnels leading asfar bs 800 yds. toMinami Village.(TA-183W)

Entrance to cave(TA-198X)

22


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Caves

Interior view of extensive cavenetwork underCD gun over East BoatBasin. (TA-183X)

Entrance to cave.(TA-216D)

2


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Coves

One of many caves In forward slopes of hillsguarding airfield No. 2.MGs and small arms firewas received from thesepositions which providedexcellent observation ofthe entire East Beacharea. (TA-183H)

Interior view of caveshowing steps leadingdown and passagewayleading off to eitherside where troopswere quartered.(TA-198X)


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Caves

Interior view of entrance leading down Into cave. (TA-199UJ

Interior view of passageway In cave. (TA-132C) Entrance to two-story cave. (TA-199U)2


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COAST DE FEN SE - AR TILL ER Y- 15 cm CD GUNS

155 mm (15 cm) CD gun show-Ing destruction caused bynaval gun fire. Reinforcedconcrete 4 ft. thick. Entrance to these casematesIs In the rear connected by-cave networks which wereused as personnel shelters,food storage and ammunitionstorage. These guns wereset about 15 yds. apart andhad a field of fire cover-Ing the entire West beachesand areas out to sea.(TA-216D)

Ruins of 155 mm (15 cm)CD gun. (TA-216D)

26


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15 cm CD GUNS

Rangefinder placed betweentwo CD guns in same areaused as part of fire control equipment.(TA-216D)

Front view of blockhousehousing a 155 mm (15 cm)CD gun . Destructioncaused by naval gun fire,Entra nce Is in rear ofblockhouse with adjoining caves throughout forpersonnel shelter, foodstorage and ammunitionstorage. (TA-216D)

27


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15 cm CD GUNS

Rear view of 155 mm (15cm) CD gun In blockhouseshowing destructioncaused by naval gun fire .(TA-216D)(SW)

Ruins of casemate containing 155 mm (15 cm) CD gun,Two such Installations,built of reinforced con crete with walls over 4ft. thick and connectedwith rangefinder and OP,were located on the edgeOf a cliff at TA-21 9A.

28


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14cm CD GUNS

View of cave entranceleading from casemated140 mm (14 cm) CD gunback. Into the base ofthe crater.(TA-132L)

Breech-block view of oneof the 140 mm (14 cm)guns at the foot of Suribachl showing destruction. It is known that"these guns were silencedprior to our landing butruins of these installations provided cover forthe enemy and affordedan opportunity to inflictcasualties on troops advancing toward Mt. Suribachl. (TA-132K)

29


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14 m CD GUNS

Front view of one of the140 mm (14 cm ) CD gunsshowing destructioncaused by naval gun fire(TA-132K)

Front view of one of the140 mm (14 cm) CD gunscasemated at the foot ofMt. Suribachi. They wereconstructed of reinforcedconcrete about 4 ft.thick with tunnels leading from the rear intothe base of the mountainand connecting each install ation . These tunnels also connected topersonnel shelte rs, foodstorage and ammunitionstorage. (TA-132K & L)

30


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14 cm CD GUN S

STAIRS TO AA GUN ON ROOF

ENTRANCE TO ADJOINING ROOM

Plan view of 140 mm (14 cm) CD gun with 30-footfire port. This Is one of the four emplacem entsfound at the base of Mt . Surlbachi. (TA-132 K)

3


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12cm CD GUNS

y

m

pm Close-up of 120 mm (12 cm)CD gun showing destructionr of Installation by naval- ) gun fire and constructionof casemat e. (TA-183W)

*

\/ :i ^ ^ f t V . ; &"i . * . ^ ^ ^ ^?) ' ' ^ " H B L ^ ' * ^ * ^1Vi I\

120 mm (12 cm) CD guncasemated In 4 ft. reinforced conc rete . Allfour guns In this battery were destroyed bynaval gun fire.(TA-183W)

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12cm CD GUNS

View showing field of fireaffonded 120 ram (12 cm )gun emplaced in casemateoverlooking East anchorages and beaches.(TA-183Y)(SW) corner.

120 mm (12 cm) CD gun d estroyed by naval gun fire.This 4-gun battery wasexcellently camouflaged.They were not observed inaerial photos until theblast effect of naval gunfire removed protectingcamouflage. (TA-183W)

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12 cm (S ho rt) Novol Guns

The field of fire of 120mm (12 cm) short navalgun firing down WestBeach and areas out tosea. Completely knockedout by naval gun fire.(TA-146Y)

Front view of 120 mm(12 cm) short naval gunfiring down West Beach.(TA-146Y)

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12 cm (Shor t) Noval Guns

120 mm (12 cm) shortnaval gun casemated Isix feet of reinforcedconcrete. This Is onof two such guns InTA-183X.

l0 mm (12 cm) shortnaval gun sited to fireon East Beaches.(TA-183X)


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12 cm (S ho rt) Nava l Guns

Rangeflnder for 120 mm(12 cm) short naval gunbattery. (TA-183X)

120 mm (12 cm) shortnaval gun not damaged bynaval gun f ire, case-mated In flve-feet-thlckreinforced concrete withtwo adjoining rooms forliving quarters and ammunition storage. OP ontop of this Installationhad a ladder leading upfrom the Inside to It.This gun was put out ofaction by flamethrowersand small arms fire.(TA-148L)

36


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12 cm Naval Guns

120 mm (12 cm) shor t navagun emplaced as a coas tdefense gun.

' . ' > 0 0 0 . ? 0 . 0 ^ _ rt O O o n ^ ^ O

o;o"o?,v

GUN ROOM . AMMO. ROOM LIVING SPACE

| FIRE-PORTh4'- tf1 9"- 0"

0,oSo.oo

-6'- 6" r- 9" 6'-0" -O'U'-0"

CP e , , &,O O T>

,00 0n o . o o

O o 0 o

-REINFORCED CONCRETE

Plan view of casemate for120 mm (12 cm) short navalgun. (TA-146Y) 3


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8 cm CD GUNS

Inside view of casemated76 mm (8 cm) dual purposegun used as CD gun.(TA-147V)

Front view of casemated76 mm (8 cm) CD gun showing construction of 3 ft,reinforced concrete.This gun was not damagedby naval gun fire but believed to ha"e been putout of action by flamethrower and small armsfire. Field of fire345 - 15.(TA-147V)

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8 cm CD GUNS

> ' ( - " % , '1 p. *: 5-0'* " * ' '

AMMO. 81 LIVINGSPACE

'^:\^v-fC T c l I r~i ' * ' . * ^ -1

Plan view of casemate for8 cm CD gun. (TA-147C)> * i i " . .-." " . . v . ' ' v % ' ' - * * ; v

ANTIAIRCRAFT AND DUAL PURPOSE BATTE RIES - 1 2 0 mm DP

Four-meter rangefinderused in con junc tion w ith120 mm (1 cm) du al purpose b a tt e r y . (TA-202X)


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12cm DP GUNS; ; , ; . / ; . : . .. .;

120 mm (12 cm) dual purpose gun showing revetmentmade of oil drums filledwith sand. Ammunitionready boxes were placedIn the side of the revetment This Is one of theguns In a battery of six,and It Is known that allpersonnel lived at theirguns In an adjoiningunderground room whichwas found at each emplacement. (TA-147R)

Underground shelter forpersonnel and ammunitionconnected to 120 mm (12cm) dual purpose emplacement. The walls and roofwere constructed of reinforced concrete 2 ft.thick, and the Installation was covered withearth having naturalvegetation for camouflage(TA-182U)

"lli:;:

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12cm DP GUNS

Onene of thirty-one 120 mm(112 cm) dual purpose gunsshehowing excellent observation for firing groundmissions. (TA-182U)

Director for 120 mm (12 dual purpose battery locted In small cut stonerevetment. Rangefinderwas located on an adjacewooded knoll. (TA-182U)


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12 cm DP GUNS

Side view of 120 mm (12 cm)dual purpose gun showing-attempted camo ufla ge. Thisproved very ineffective.(TA-U7R)

Director for 120 mm (12 cm)dual purpose batt ery. Al though no damage can beobserved In the photo, thisInstallation was out ofaction prior to our landing. (TA-147R)

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10 cm DP GUNS

Camouflage net Is notedover 100 mm (10 cm)(65cal.) twin-mount navaldual purpose gun. Theemplacement was dug Into a depth of 8 ft. to10 ft. with no retaining walls. (TA-217G)

This Is one of two 100 mm(10 cm) twin-mount dualpurpose naval guns foundat TA-217G. A third revetment was under construction. However, noadditional gun was foundon the Island.

4


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10 cm DP GUNS

Front view of 100 mm (10cm) twin-mount naval DPgun showing depth ofrevetment as compared toshield on gun. Camouflage net covers shieldand part of barrels.(TA-E17G)

Rear view of 100 mm (10cm) twin-mount naval DPgun, 65 caliber.(TA-217G)

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10 cm DP GUNS

Plan view showing size of 100 mm (10 cm) DP gun revetmen t. Thisrevetment was dug Into the ground approximately 8 ft. to 12 ft.with rock piled around the sid es. (TA-217G)

I100 mm (10 cm) DP gun with camouflage torn away.

4


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7 cm AA GUNS

--:

& '

75 mm (7 cm) type 88 AAgun showing poorly constructed revetment whicheasily crumpled from theeffects of our artilleryNote the camouflagepainted on the barrel ofthe gun. (TA-235V)

AA director in lava rock,emplacement for six-gun75 mm (7 cm) type 88 AAbattery. (TA-183D)

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7 cm AA GUNS

Hastily emplaced 75 mm(7 cm) type 88 mobileAA gun. The beginningof a revetment is noted(TA-218C)

75 mm (7 cm) type 88 AAgun. (TA-235V)

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7 cm AA GUNS

Although the trail legsof this 75 mm type 88AA gun were spread, thediameter of this emplacement measured only16 ft. (TA-183D)

ROCKS STACKED 1-6" THICKFOR WALL

Plan view showing dimensions of a typical 75 mm(type 88) AA gun emplacement found on Iwo Jlma.

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Triple-mount 25 mm AA in lava rock emplacemeSeveral of these mountbelieved to have beentaken from wrecked LSMwere found. (TA-166C)

Triple-mount 25 mm AA MGemplaced with a batteryof twin-mount 25 mm AAMGs. (TA-217L)


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25 mm AA MG

25 mm twin-mount automatic AA MG showing gunin emplacement whichwas constructed of lavarock, blocks. Noteammunition storage boxes lying around sidesof revetment. Therewas a passageway leading from revetment tounderground shelter.(TA-148P)

"it "***'25 mm AA MG. This twin-mount, along with twoother twin-mounts, wasemplaced in a batterywith three single-mount25 mm AA MGs. (TA-148P)

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25 mm AA MG

5 mm twin-mount with onegun removed. It is believed that some of thesepositions had one gun removed in order to reducevibration. (TA-201U)

25 mm twin-mount automatic AA gun in lavarock emplacement.(TA-182Q)

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25 mm AA MG

25 mm twin-mount automatic AA position connected to earth-coveredliving quarters andammunition storage overlooking airfield No. 1.(TA-164E)

25 mm AA MG placed inrevetment using sand-filled oil drums asretaining walls, reinforced with blocksof lava rock. Notemount for two gunners,one to elevate, theother to traverse.(TA-147T)

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25 mm AA MG

25 mm AA MG emplacemenThis is a new type momodeled after the 25 twin-mount MG. (TA-14

25 mm automatic AA insmall revetment measuring ten feet In diameter.Like many AA weapons onIwo Jlma, this gun Issited also for useagainst ground forces..Considerable armor-piercing ammunition wasfound In vario us AApositions. (TA-219F)


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25 mm AA MG

Three feet of concreteprotected this ammunition box at 25 mm automatic AA position.(TA-164E)

Entrance to earth-covered partiallyunderground livingquarters at 25 mmtwin-mount automatic AA position.(TA-164E)

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25 mm AA MG

Underground shelter havifood, water and first aisupplies for personnel a26 mm twin-mount automatAA position. (TA-182Q)

General view of earth-covered structure containing 26 mm twin-mountautomatic AA position,living quarters forpersonnel and ammunitionstorage. Note the natural grass for camouflage(TA-164E)


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25 mm AA MG

25 mm AA single-mount MOemplaced In revetmentusing sand-filled oildrums as retaining walls.Ammunition was storedaround the sides of therevetment as shown Inpicture. (TA-147T)

AEMPTY AMMO. BOXES USED FOR W ALLS

, LOG AND DIRT COVERED SLEE PING SPACE

Plan view of 25 mm AAgun position.

GUN BASE BOLTED TOWOODEN TIES 6" SQUARE

SIDE VIEW OF BASE


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25 mm AA MG

Plan view of casema25 mm MG p o si t i o n .

STEPS CUTINTO WALL

Pl an view of a 25 mmAA (t r ip le-m ou nt) gunrevetment. (TA-217I)


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25 mm AA MGV i V

2 5 mm AA g u n .

Triple-mount 25 mm AA gun.

8


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13 mm MG

13 mm single-mount MGemplaced on top of Mt.Suribachl in veryhastily constructedrevetment . Nine ofthese weapons werefound around the topof Mt.. Suribachl.(TA-132P)

13 mm MG revetment sh owing how natural vegetatiproved to be effectivecamouflage. (TA-132H)

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13 mm MG

13 mm twin-mount w ithsingle seat attached tomount in rear of gun .Previously encounteredtwin-mount 13 mm MGshave been equipped withseats on each side ofthe gun. (TA-183X)

##

13 mm single-mount MGemplacement carved outof lava rock. Noteammunition storagecave at left of gun.(TA-183C)

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Seorchlights

Trailer carrying 150 cmsearchlight from whichtarpaulin had not beenremoved when located.(TA-818H)

View of AA mobile searchlight showing cliffs andledges which were used asprotection against bomb-Ing, strafing and artillery fire. (TA-217D)

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Searchlights

Revetment containingtruck with generatorfor mobile searchlight. (TA-217Q)

Revetment showing searchlight comparator emplaced,(TA-132A)

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Searchlights

\ 4 " '

Radar adaptation forsearchlight control.(TA-217C)

150 cm searchlight Infixed position. Arevetment of loose rock,has been partially blowaway. Attempts tocamouflage such positions with vegetationwere not effective.(TA-218V)

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SearchlightsELECTRIC CONTROL BOXBUILT IN WALL

SANDSTONE ROCKSTACKED 2'- O" THICKFOR WALL

SIZE OF LIGHT COMPAREDTO BASE AND PIT

Plan view of revetment for 150 cm searchlight,(TA-217C)

150 cm mobile searchlight protected by stonerevetment. A truck with generator .for thesearchlight was found In a revetment close by.(TA-217Q)

Searchlight position for 150 cm searchlight.

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BLOCKHOUSES

Inside view of blockhouseshowing intricate construction of various room s. Inadditio n to housing a 25 mmMG and a 7.7 mm HMG, It Isbelieved that this blockhouse was used as a CP forthe defense of the EastBeach. (TA-149A)

: i

\

Embrasure of blockhousehousing a 47 mm AT gunshowin g tube and carriage .(TA-165J)

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Blockhouses

Front view of fire portfor single-mount 25 ramMG In blockhouse .(TA-165N)

Cupola with four observation ports. The roof isthree feet of reinforcedconcrete, and the cupolacan accommodate a manfive feet tall. (TA-165N)

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Blockhouses

Front view of blockhouseshowing fire port housinga 25 mm machine cannon.(TA-147C)

Rear entrance to blockhouse. In addition toa 25 mm MG, a model 97.7 mm HMG fired fromthe opposite side.(TA-165N)

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Blockhouses

Interior view of blockhouse housing 120 mm(12 cm) short naval gunshowing damage Inflictedby naval gun fire.(TA-146Y)(SE)

Front view of blockhousishowing fire port andrevetted sides to firelane. (TA-147C)(E)

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Blockhouses

Interior view of blockhouse housing a 25 mmmachine cannon.(TA-147C)

Front view of blockhousehousing a 120 mm (12 cm)short naval gun firingnorth along the beach.It is constructed ofheavily reinforced concrete with the fireport being protected byrevetments faced withsand-filled oil dru ms.

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Blockhouses

4 WAY OBSERVATION TOWER4L0" SQUARE, I4 L O " H I G HFROM DECK

Plan of blockhouse for 47 mm AT position at TA-1 81B. This position hasan adjoining room for a HMG, also space for ammunition storage, foodstorage and living quarters.

SANDBAGS

CONCRETEFIRING TABLE(MACHINE GUN)4-0" X 3 -0" X 3-9 HIGH

1 4 WAY OBSERVATION TOWER |2 '-O" HIGHPROTRUDING 3'"0" ABOVE'TOP OFBLOCKHOUSE WITH 3 L 0 " X ZLd' HIGH(INSIDE) OPENING AT BOTTOM

Plan of blockhouse for 3? .mm A T position at TA-215Y,

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COVERED AR TILLER Y EMPLACEMENTS 120 mm Howitzers

120 mm (12 cm) type 38Howitzer In coveredartillery emplacement.This position was builof cut-stone with aroof of logs. Trees Ithe area hid the position frera the ai r.(TA-219L)

120 mm (12 cm) type 38Howitzer. (TA-201S)

7


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120 mm Howitzers

Front view of 120 mm(12 cm) Howitzer emplacement showing fireport and surroundingareas. (TA-217A)

**f%$120 mm (12 cm) Howitzer !In hast ily constructedemplacement. (TA-201S)

72


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120 mm Howitzers

120 mm (12 cm) type 38Howitzer. (TA-219L)

Close-up of 120 mm(12 cm) Howitzer position. Note screen usedto camouflage opening.(TA-201S)

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120 mm Howitzers

LOG LAID ACROSS DECKCHOCK WHE ELS O F GUN

Plan view of a 120 mm (12 cm)Howitzer position.

ROCK LINED PASSAGELEADING TO AMMO.STORES

Interior view of a 120 mm (12 cm) Howitzeremplacement showing gun in firing position.

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75 mm (Type 3 8 ) Field Guns

Front view of casemated75 mm (type 38) fieldgun emplacement locatedat the base of Suribachlfiring down East Beach.(TA-132R)

Interior view of 75 mm(type 38) fl-eld gun emplacement snowing extentof damage. (TA-132R)

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75 mm (Type 38 ) Field Guns

Interior of.75 mm (type 3field gun position.(TA-218A)

Inside view of 75 mm(type 38) field gunposition destroyed.(TA-201V)

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75 mm (Type 3 8 ) Field Gun

Ruins of casemated 75 mm(type 38) field gun.(TA-201V)

Casemated 75 mm (type 3 8)field gun overlookingEast Boat Bas in.(TA-167A)

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75 mm (Type 3$> Field Guns

A 75 mm (type 38) fieldgun was located in thiswell-concealed concreteemplacemen t. A similarposition was locatednearby, and ammunitionwas stored in caves atthe rea r. (TA-218N)

75 mm (Type 9 0 ) (Field Guns)

Front view of a 75 mm (type 90 ) AT gun emplacement showing how empla cementswere constructed to blend in with the natural te rrain.78


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75 mm (Type 9 0 ) Field Guns

Rear view of 75 mm (type90) field gun In casematedpositio n. This positionfired down runway of airfield No. 2. (TA-200Y)

Alternate position for75 mm (type 90) fieldgun hastily constructed,(TA-200-0)

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7 5 mm (Type 9 0 ) Field- Guns

Interior view of 75 mm(type 90) field gun.(TA-217H)

Front view of 75 mm(type 90) field gunshowing constructionof emplacement andhow well the terrainwas utilized forcamouflage. (TA-217H)

80


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4 7 mm Anti - Tank Guns

Front view of emplacementshowing thickness of concrete and nature of terrain of surrounding a rea.Originally housed a 47 mmAT gun. Field of fire200 - 250. (TA-215T)(NE)

Interior view of 47 mm ATemplacement showing damagedone to gun. (TA-132C)

It. V *,-

8


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47 mm Anti-Tank Guns

Front view showing theemplacement for 47 mmAT gu n. Note rice-bagrevetted wall s.(TA-181B)

Artillery emplacement fo47 mm AT gun built of lavblocks with a log roof,earth cover ed. The fireport Is at the rig ht. Aconnecting MG positionbuilt of lava blocks maybe seen at center.(TA-182W)

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47 mm Ant i -Tank Guns

Front view of 47 mm ATgun shelter showingwhere gun was kept whennot In position.(TA-132B)

47 mm AT gun emplacementmade of materials at handincluding logs and lavarock. (TA-183N)


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Rear view of concreteposition for 47 mm ATgun. The field of firecovered the southernpart of airfield No. 2seen in background.(TA-199W)

Typical 47 mm AT gunshelte r. At the farend of this shelterwas an.entrance to acave and tunnel system which was morethan 800 yds. longand had 14 ent ranc es.It housed two Bn CPs .(TA-183Q)

T:

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4 7 m m Anti-Tan k Guns

DRUMS FILLED WITH SAND

o o q o oAMMO. STORAGE

[' 4 \ TRENCH TOSMALL ROCKS AMMO- DUMP


96/130


37 mm (type 94) AT gun Inemplacement constructedof sand-filled fuel drumswith log roof. (TA-182W)

Front view of 37 mm ATemplacement showingdestruction caused byartillery fire.(TA-98D)

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OPEN AR TILLE RY EM PLA CE ME NTS 4 7 mm Anti-Tank Guns

One of two supplementaryemplacements for 47 mmAT gun In nearby coveredprimary positions. Note,logs placed over position to support camouflage. (TA-183L)

47 mm AT gun coveringroad at TA-201W.

87


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37mm Anti-Tank Guns

37 mm AT gun In openemplacement showinghow terrain aided Inprotecting the position. (TA-217G)

37 mm AT gun In openemplacement. (TA-217G)

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MORTARS 320 mm Spigot Mortars

Photo of 320 mm (32 cm) spigot mortar projectile.

320 mm (32 cm) spigot mort ar position showingnatural camoufl age. Heavy screen garnished 320 mm (32 cm) spigot mortar In firing position. (TA-199K)with brush was placed over the opening forcomplete concea lment. (TA-183L)

89


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150 mm Mortars

View of 150 mm (15 cm;morta r la firing position located near another 150 mm mortarposition under constru ctio n. Note theearth embankment usedin place of baseplate.(TA-198X)

Entrance to a cave whichhad a 150 mm (15 cm)mortar set up in the entrance . When not actually firing, the mortarwas drawn back Into thecave for protection andconcealment. (TA-216J)

90


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150 mm Mortars

View of the fire port ofa 150 mm (15 cm) mortarposition. Adjoiningthis emplacement werepersonnel quarters, foodstorage and ammunitionstorage. (TA-198X)

150 mm (15 cm ) mortarposition under construction. (TA-198X)

91


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150mm Mortars

One of a battery of four150 mm (15 cm) mortarpositions. Note aimingstakes on wal ls. Theseemplacements are approximately 11 feet In dia meter and had ammunitionstored In a small coveredadjoining cham ber. A firetrench led to living qua rters for the mortar crew.(TA-184I)

REINFORCED CONCRETE WALL CONCRETE/TABLE 3 L4".HIGH

CAV E IN

BLAST WALL OF l"0" SANDSTONEBRICK 4 L2 " HIGH PROTECTEDWITH EARTH

Pla n view of a 150 mm (15 cm) m or tar p o s it io n . (TA-198X)

92


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81 m m Mortars

Type 3, 81 mm mortar usedin 120 mm (12 cm ) dualpurpose gun emplacement.(TA-182U)

Close-up of 81 mm mortarin position at T A-18 2U.Some antiaircraft 81 mmmortar projectiles werefound on the island.

93


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81 m m Mortars

View of 81 mm mortaremplacement. Notehow foliage and terrain were used forconcealment.(TA-181D)

81 mm mortar positionmade of rice ba gs.The mortar Is concealefl par tial ly bybrush covering partof the emplacement.(TA-182M)

94


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Grenade Launchers

Well built cut-stone andlog position for grenadelauncher. (TA-181T)

Grenade launcher position. (TA-182M)

95


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R O C K E T S 2 0 0 mnrTRocket Launcher

200 mm (20 cm) rocketprojectiles in shelteradjoining launchingsite. (TA-183M)

Mortar-type 200 mm(20 cm) rocketlauncher.

96


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200 mm Rocket Launcher

t v

200 mm (20 cm) mobilerocket launcher Incamouflaged emplacement. (TA-183M)

View of 200 mm (20 cm)rocket launcher fromshelter for ammunition.(TA-183M)

97


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2 0 0 mm Rocket Launcher

Close-up of 200 mm(20 cm) mobile rocketlauncher. (TA-201I)

200 mm (20 cm) rocketlauncher in coveredposition with a framebuilt over it to sup port camouflage.(TA-201I)

98


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250 kg Rocket Launcher

This captured picture of the V-trough rocket launcherfor a 250 kg. aerial bomb is Identical to the rocketlauncher used on Iwo Jlma.

9


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63 kg Rocket Launcher

Ruins of V-trough rocketlauncher in deep drawwith rock dam for protection from seaward sideRocket motor like onenoted in trough and 63 kg.bomb were stored in cavenoted to left of picture.(TA-184P)

V-trough rocket launcherfor 63 kg. bomb in natural emplac ement formedby deep draw. Ammun ition was stored in adjoining cav e. (TA-184P)

100


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PILLBOXES

Heavily constructed pillbox well camouflaged.: Note limited field ofI fire. (TA-183U)

Pillbox sited down runwayof airfield No. 1. Camouflage net conceals thefire lane. (TA-183X)

101


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Pillboxes

Entrance to pillbox(TA-147M)

View of entrances to twoJap pillboxes firing toward, airfield N o. 1. Itwas not unusual to findpillboxes this close together. (TA-183L)

102


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Pillboxes

Inside view of pillboxfor heavy machine gun.(TA-165E)

Front view of pillbox showing fireport. This position can be seen Pillbox having a roof of concretetwo feet thick covered with rockonly from the front because of natural concealment. (TA-198R) and earth. The natural camouflagemakes detection difficult. (TA-182R) 103


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RIFLE PITS

Rear view of rifle pitconstructed from a tankturret affording excellent observation of terrain sloping south fromairfield No . 2. Sandbags and camouflage wereblown away. (TA-182E)

Front view of one-manrifle pit showing fireports. These positionswere not only excellentrifle pits but also goodobservation posts forflanking AT posit ions.(TA-181B)

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Rifle Pits

Rifle pit carved out oflava blo cks . (TA-183R)

k

,,,,.

Tank turret mounted in field, near beach used as Entrance to concrete rifle pit. Theserifle pit. (TA-165 E) positions were found scattered throu ghout the South ern are a. (TA-181B)105


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TANKS

Japanese medium tank em-placed in a fixed position to act as a pillbo x.Rugged terrain throughout the area dictatedthis use of tank. Thistank had a 57 mm gunmounted in the turret.(TA-21QS)

Rear view of Jap model 96light tank revetted inposition to fire on approaches to airfield N o.2.

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Tanks

g tank, mounting a37 mm gun, in tank servicing area. (TA-EOOY)

Tank in fixed positioncamouflaged with rocksand vegetation whichhave been largely blownaway. (TA-200E)

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Tanks

Destro yed Jap 47 ram AT gun and revetted model 97Jap medi um tank mounting 4 7 mm gun on foot ofslope of Hill 382 . (TA-200Y)

Revetted and camouflagedmedium tank mounting 47mm gun, model 97 .(TA-201G)Rear view of Jap mediumtank model 97 revettedIn foot of slope of Hill382. (TA-200Y)

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DUMMIES

Dummy covered artilleryposition . This emplac ement consisted of a dummy gun with a woodenframe supporting sandmoun d. Rocks were placedon either side of thefire port to give theeffect of a fire lane.(TA-180A)

Dummy pillbox showing fireport. These positions werenume rous throughout the WestBeach area. (TA-180E)

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Dummies

Dummy gun4 Before sandwas blasted by naval gufire from around gun,this position appearedIn aerial photos to be covered artillery emplacement. (TA-166A)

This dummy pillbox consisted of no more thana mound of sand with awooden box frame tosimulate a fire portplaced on one side togive the appearance ofa pillbox. (TA-198F)

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Dummies

Dummy tank. Note detailof turret showing tankgun. (TA-216L)

Two dummy tanks made ofwood were found in thisarea. They were lightlyconstructed and couldbe moved around easily.The enemy hoped to confuse interpreters ofaerial photos. (TA-216L

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RADAR AND RADIO STATION

Radio station used asblockhouse. Note thickness of wa ll s. ' Despitethe many direct hits,this Installation had tobe cleaned out with flamethrowers. (TA-184K)

Destroyed early warning radar on Hill 382. Reinforced concrete radio station showing dire(TA-200Y) hits from artillery and infantry we apo ns.(TA-184K)

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REVETTED VEHICLES

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AIR RAID SHELTERS

Steps leading from air raid shelter.At some time a heavy machine gun wasmounted In the open ing . Note thedirec tion markers around the opening,(TA-H8A)

Entrance to air raid shelter. Thisair raid shelter was constructedwith walls of soft lava rock aroundthe entrance and leading down Intothe shel ter. Vegetation was growing over the earth cover providingexcellent camouf lag e. This Installation was not h armed throughout theoperation. (TA-148A)

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Air Raid Shelters

Interior view of airraid shelter showinghow airplane fuselagewas used to form Interior of shelter.(TA-148A)

Interior view of wellconstructed cut-stoneshelter with concreteroof. Medical suppliesindicated that this wasused as a first aidstation. (TA-164E)

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AMMUNITION STORAGE

Underground ammunitionstorage. (TA-234H)

This cave had many armsthat led off from mainpassage. (TA-234H)

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Ammunition Storage

A well camouflaged a mmuni tion storage for 81 mmmortar ammun itio n. Thisposition showed no effectsof our heavy gun fire orartillery fire. It wasJust below the ground andextended back approximately 30 feet and led toa large room with connecting tunnels leading toadjoining rooms.(TA-199K)

Anti-tank ammunition storage dug into a bluff. Underground ammu nition storage for 25 mm MG.(TA-200Y) (T-181G)

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MISCELLANEOUS

Gasoline motor to generatpower for communications.(TA-164J)

Switchboard for publicaddress system at airfield No. 1. (TA-164J)

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Miscellaneous

Interior of communicationsroom In earth-covered concrete structure at airfield No . 1. This position was knocked out byflamethrowers. (TA-164J)

General view of earth-covered stone and concrete housing for publiaddress system at airfield No . 1. (TA-164J)

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34895017 defense installations on iwo jima usa 1945

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