Time Astra

Schematic plan · World War II (Okinawa)

Battle of Tarawa

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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, Mixed groundCentreLeft wingRight wingReserveGunsCentreLeft wingRight wingReserveGunsArmourArmour0250 m500 mN

USA (US 2nd Mar Div(-), 9,000 men under Mg Smith) attacked Japan (Jap Gilbert Islands Garrison Force(-), 4,836 men under Adm Shibasaki) in Japan. The CAA Database of Battles records 48.3 hours of fighting on a front of 1.2 km, a frontal attack against fortified defense, and that USA won. Losses: USA 3,302 (37%), Japan 4,836 (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

Mg Smith

UnitArmMen
USA left wingInfantry1,781
USA centreInfantry2,374
USA right wingInfantry1,781
USA reserveInfantry1,484
USA artillery (278 guns)Artillery1,350
USA armour (46 tanks)Armour230
Mg SmithCommander—
In this plan9,000

Japan

Adm Shibasaki

UnitArmMen
Japan left wingInfantry970
Japan centreInfantry1,293
Japan right wingInfantry970
Japan reserveInfantry808
Japan artillery (53 guns)Artillery725
Japan armour (14 tanks)Armour70
Adm ShibasakiCommander—
In this plan4,836

What the sources report

USAJapan
Strength, this plan9,0004,836
Losses, this plan3,3024,836

In the CAA Database of Battles

CDB90 no. 517, “Tarawa-Betio”, compiled for the US Army to study what decides battles. These are the figures a what-if engine can be calibrated against.

Fighting
48.3 hours
Winner
the attacker
Terrain
Rolling, Mixed
Weather
Dry, Sunny, Temperate, Autumn, Temperate
Defender’s posture
Fortified defense
Front width
1.2 km (attacker), 1.2 km (defender)
ForceStrengthLossesHorseGunsPlan and outcome
USAattacker9,0003,3020278Frontal attack; Breakthrough
Japandefender4,8364,836053Defensive/offensive plan; Frontal attack; Repulse; Annihilated

Attacker’s advantages logistics +1 · momentum +1 · initiative +1 · air superiority +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.