BatDiv

A BatDiv or BATDIV was a standard U.S. Navy abbreviation or acronym for "battleship division." The Commander of a Battleship Division was known, in official Navy communications, as COMBATDIV (followed by a number), such as COMBATDIV ONE.

BatDivs existed from at least 1913, when there were four Battleship Divisions in the US Atlantic Fleet.

By April 1917, with the American entry into World War I, there were at least nine Battleship Divisions, as BatDiv 9 was dispatched to operate with the Royal Navy's Grand Fleet.

Before the Second World War, the U.S. Navy battleship force was organized into five Battleship Divisions of three battleships each. Only two of these BATDIVs were composed of three battleships of the same class, but mixing battleships of separate two-ship classes to form three-ship BATDIVs was facilitated by the "Standard type battleship" concept of the US Navy, a design concept developed before 1922 calling for uniform top speed of 21 knots (39 km/h) and a tight tactical radius of 700 yards (640 m) for all battleships of the Nevada, Pennsylvania, New Mexico, Tennessee and Colorado classes.

Stationed at Pearl Harbor as part of the U.S. Pacific Fleet were three battleship divisions: Pennsylvania and Arizona with Nevada (BatDiv 1); Tennessee and California with Oklahoma (BatDiv 2); and Colorado, Maryland and West Virginia (BatDiv 4). These nine battleships were intended to counterbalance the ten battleships of the Imperial Japanese Navy. At the time of the Pearl Harbor Attack, Pennsylvania was in dry dock and Colorado was being refitted at Bremerton Navy Yard, Washington State. Arizona was mated with Nevada and Oklahoma at that time.

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