I used to know USS Arizona survivor Glenn Lane, who flew in the ship's scout planes. He said the red tops were primarily for aerial identification for the aviators. He described how difficult it could be, in a bumpy, vibrating aircraft, to identify battleships with similar appearances in varying weather or lighting conditions. Since the Arizona usually operated with the Oklahoma and Nevada, 2 of which are sister ships and the third VERY similar, the chances for landing by the wrong ship for hoisting aboard were apparently pretty great.
Forward turrets identfied the BB division (red was division 1, white was division 2, etc) and turret 4 identified the ship within the division. Red was for the flagship, white for #2, blue for #3. So since the Arizona was flagship of BatDiv One, the forwards were red for the division, #4 red for being the flagship. Pennsylvania was flagship of BatDiv Two; therefore she had white on turrets 1 & 2, and red on #4 as the flagship.
This post has been edited by Andrew D. the Jolly Rogers guy: 04 April 2012 - 07:37 PM