 On 14 July , both ships were reassigned to Battleship Division 2 and Nagato became the flagship of the 1st Fleet . She remained in Japanese waters training until August 1942 . Mutsu was transferred to the Advance Force of the 2nd Fleet on 9 August , and departed Yokosuka two days later to support operations during the Guadalcanal Campaign . She arrived at Truk on 17 August . On 20 August , while sailing from Truk to rendezvous with the main body of Vice Admiral Chūichi Nagumo 's 3rd Fleet , Mutsu , the heavy cruiser Atago , and escorting destroyers unsuccessfully attempted to locate the escort carrier USS Long Island in response to a flying boat detection of the American ship . 
