Ships
- IJN Aoba Captain from 4 June 1944
Chusaburo Yamazumi was a captain in the Imperial Japanese Navy. On 4 June 1944 he took command of the heavy cruiser Aoba, relieving Kamenosuke Yamamori. Aoba, the lead ship of her class, had been completed in 1927 and was already a veteran of the Pacific war. She had covered early invasion landings, then fought in the night actions off Guadalcanal, including Savo Island and Cape Esperance. At Cape Esperance, American shellfire tore up her upper works and killed the rear admiral whose flag she flew. An air attack in April 1943 damaged her machinery so severely that, after a long repair, her best speed was only about 25 knots. Through 1944 she served in the south with Cruiser Division 16, on escort work and short operations far from the main battle line she had known earlier in the war.
The cruiser's wartime captaincy had already changed hands several times. Late in 1942, while Aoba was still recovering from Cape Esperance, Tsutau Araki held her for a brief additional tour, his principal command being the heavy cruiser Chikuma. Yamamori then had her for the long stretch of southern duty that followed her return to service at the end of 1943. Yamazumi came aboard on 4 June 1944 with the ship still flagship of Cruiser Division 16. Early that June the division had put to sea with the light cruiser Kinu and destroyers of the 27th Division in the attempt to run reinforcements toward Biak. The attempt was called off, and Aoba went back to the anchorages of the Southwest Area.
In July she refitted at Singapore. The yard added four triple mounts and fifteen single mounts of 25-millimeter antiaircraft guns, and fitted a Type 22 radar for searching the sea surface. She then lay at Lingga and trained with the ships collecting there for the next fleet operation. On 11 October she collided with Kinu. The damage to both ships was light, and Aoba remained available for the move against the American landing on Leyte.
On 18 October Aoba left Lingga with the heavy surface force. That afternoon Cruiser Division 16 was shifted to the Second Striking Force and given a transport task, carrying army troops toward Leyte rather than standing in the gunnery battle. Before dawn on 23 October 1944, southwest of the entrance to Manila Bay, the American submarine Bream attacked. Lookouts saw torpedo tracks, and Yamazumi ordered full right rudder and full speed. One torpedo struck the starboard side in the forward engine room. Eighteen men were killed at once, three were wounded, and one of the wounded later died. Another man was missing. The ship took on a list of about ten degrees, and the list grew as water kept coming in. Her engines soon stopped. Kinu took her in tow and brought her into Manila at a few knots, where emergency work began at the Cavite navy yard.
Carrier aircraft bombed Aoba while those repairs were still incomplete. The yard made her fit only for a slow passage. She left the Philippines in a convoy bound for Japan, and on 6 November American submarines attacked that convoy off Luzon. Aoba came through and entered Kure on 12 December 1944. A full restoration would have occupied a dock for too long, so she remained in the harbor as a reserve ship, with a reduced crew, her guns kept for local defense against aircraft. On 1 January 1945 Yamazumi left the command. Seiroku Murayama then held Aoba together with his post as head of the Kure naval port department. In the air raids of 24 and 28 July 1945 the cruiser was hit again and settled on the shallow bottom at Kure. Yamazumi's months aboard had been her last time underway.