 The ships were reconstructed from late 1933 to mid @-@ 1936 . In August 1937 , the sisters transported 3 @,@ 749 men of the 11th Infantry Division to Shanghai during the Second Sino @-@ Japanese War . Their floatplanes bombed targets in Shanghai on 24 August before they returned to Sasebo the following day . Nagato became a training ship on 1 December 1937 until she again became the flagship of the Combined Fleet on 15 December 1938 . The ship participated in an Imperial Fleet Review on 11 October 1940 . The sisters were refitted in 1941 in preparation for war , which included the fitting of external degaussing coils and additional armor for their barbettes . 
