(Type A Standard Cargo Ship)
Tabular Record of Movement
© 2012-2017 Bob Hackett
E July 1943:
Koyagishima. Laid down at Kawaminami Kogyo K. K. as a 6,440-ton Type 1A Standard Cargo Ship for Toyo Kisen K. K. of Kobe.
E September 1943:
Launched and named GETSUYO MARU.
Completed and chartered by the Imperial Army (IJA). Departs Japan for Shanghai in an unidentified convoy. 
8 October 1943:
GETSUYO MARU departs Shanghai for northern Kyushu in convoy MO-805 also consisting of four unidentified merchant ships escorted by minelayer TAKASHIMA.
19 October 1943:
Departs Imari Bay in convoy SHI-901 also consisting of two unidentified merchant ships escorted by patrol boat PB-38.
6 November 1943:
Departs Shanghai for northern Kyushu in convoy MO-503 also consisting of two unidentified merchant ships escorted by minelayer TAKASHIMA.
3 December 1943:
Departs Takao for Mutsure in convoy No. 224 also consisting of INARI, KOSHIN, MANKO, MIIKESAN, MURORAN, MYOGI, SAN LUIS, SAN PEDRO and YUBAE MARUs escorted by torpedo boat MANAZURU.
7 January 1944:
At 1500, GETSUYO MARU departs Moji for Takao in convoy No. 127 also consisting of ASUKA, HOKOKU, IKUTAGAWA, KINREI, NIKKI, ROKKO, TOYOKUNI and YAHIKO, MARUs escorted by destroyer KARUKAYA and minesweeper W-27.
10 January 1944:
At about 1230, LtCdr (later Cdr) Royce L. Gross' (USNA '30) USS SEAWOLF (SS-197) attacks the convoy on the surface in heavy weather. SEAWOLF torpedoes and damages YAHIKO MARU, then torpedoes ASUKA MARU. Hit in the engine room, she sinks by the stern at 1239. 15 passengers and 23 crewmen are KIA.
GETSUYO MARU and KARUKAYA rescue 105 survivors in the storm. GETSUYO MARU tows YAHIKO MARU towards Naha, Okinawa, but SEAWOLF tracks them and torpedoes both ships. At 2345, YAHIKO MARU is hit by two more torpedoes and quickly sinks at 27-18N, 127-40. 141 troops and 15 crewmen are KIA.
GETSUYO MARU also sinks immediately at the same location. 20 men are KIA.
 Always a civilian vessel.
Thanks go to Erich Muehlthaler of Germany.
to IJA Transports