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Schematic plan · World War II (Okinawa)

Iwo Jima - Final Phase

All battlesBattle of Iwo Jima: engagement 3 of 3The event in the chronicleWikipedia
A schematic plan, generated from the statistics of the CAA Database of Battles: the armies' size and width, the hours of fighting, the plan of attack and the outcome are as recorded; the ground and the positions are not.
Rolling, Bare groundCentreLeft wingRight wingReserveGunsArmourCentreLeft wingRight wingReserveGunsArmourSmith0500 m1 kmN

One of the 3 engagements of the Battle of Iwo Jima recorded in the CAA Database of Battles (number 3 in date order). USA (US 3rd Mar Div(+), 32,000 men under Gen Smith) attacked Japan (Jap Chichi Jima Defense Force, 2,685 men under Gen Kuribayashi) in Japan. The CAA Database of Battles records 120 hours of fighting on a front of 1.8 km, a frontal attack against fortified defense, and that USA won. Losses: USA 3,885 (12%), Japan 2,685 (100%).

This plan is generated from those figures. It shows the shape of the battle the database describes: the size and width of the armies, the plan of attack and the outcome. It does not show where the units actually stood.

The armies

USA

Gen Smith

UnitArmMen
USA left wingInfantry6,355
USA centreInfantry8,474
USA right wingInfantry6,355
USA reserveInfantry5,296
USA artillery (804 guns)Artillery4,800
USA armour (144 tanks)Armour720
Gen SmithCommander—
In this plan32,000

Japan

Gen Kuribayashi

UnitArmMen
Japan left wingInfantry500
Japan centreInfantry666
Japan right wingInfantry500
Japan reserveInfantry416
Japan artillery (120 guns)Artillery403
Japan armour (40 tanks)Armour200
Gen KuribayashiCommander—
In this plan2,685

What the sources report

USAJapan
Strength, this plan32,0002,685
Losses, this plan3,8852,685

In the CAA Database of Battles

CDB90 no. 520, “Iwo Jima - Final Phase”, compiled for the US Army to study what decides battles. These are the figures a what-if engine can be calibrated against.

Fighting
120 hours
Winner
the attacker
Terrain
Rolling, Bare
Weather
Dry, Sunny, Temperate, Spring, Temperate
Defender’s posture
Fortified defense
Front width
1.8 km (attacker), 1.8 km (defender)
ForceStrengthLossesHorseGunsPlan and outcome
USAattacker32,0003,8850804Frontal attack; Breakthrough
Japandefender2,6852,6850120Defensive plan; Annihilated

Attacker’s advantages logistics +1 · momentum +1 · air superiority +1 · combat effectiveness +1

CDB90 (US Army Concepts Analysis Agency, 1990), tidy edition by Jeffrey B. Arnold; data under ODC-BY 1.0.

Notes

On this reconstruction

Generated automatically from the statistics in CDB90. Frontages, depths, distances, the order of events and the terrain are schematic: they follow the recorded strengths, front widths, hours of fighting, tactical plan and outcome, not maps or accounts of the battle. The sources give no hours; the timing is conjectural.

Sources

Facts gathered from Wikidata (CC0), Wikipedia (CC BY-SA 4.0) and Wikimedia Commons (licence per file); the plan and its text are timeastra’s own.