Pacific Wrecks - Type 89B Otsu Yi-Go Medium Tank (Ruri Bay No. 1)

Missing In Action (MIA)

Prisoners Of War (POW)

Unexploded Ordnance (UXO)

Chronology

Type 89B Otsu Yi-Go Medium Tank (Ruri Bay No. 1)

IJA
4th South Sea Garrison Unit
38th Independent
Mixed Brigade

Australian Army
May 24, 1945

William Bartsch 1975

Josh McDade 1999

Yoji Sakaida 2005

Justin Taylan 2005

Tank History
Built by Mitsubishi built between 1931-1939. Delivered to the Imperial Japanese Army (IJA) as Type 89B Otsu Yi-Go serial number unknown. Assigned to the 4th South Sea Garrison Unit formed at Wakayama on June 26, 1943.

Wartime History
This tank was transported from Japan via Truk to Rabaul then loaded aboard the Bunsan Maru as one of four tanks unloaded at Tarlena on northwest Bougainville in September 1943. After the American landing at Torokina on November 1, 1943 the tanks were carefully concealed. In July 1944, the tanks were assigned to the 38th Independent Mixed Brigade.

In early March 1945 then attempted to move them along the north coast road. On March 3, 1945 at 10:50am two RNZAF F4U Corsairs from No. 18 Squadron patrolling the Ruri Bay spotted a pair of Japanese tanks. Without bombs, the pair strafed the tanks, and reported them, returning with another F4U to drop 1,000 lbs bombs, and discovered a third tank. Later in the day, seven more aircraft from Piva bombed the tanks and left one on fire, and strafed the third tank which had not moved. It was hit and its ammunition exploded, 'completely wrecking it'.

During the morning of March 4, 1945 tanks in the jungle had been moved, but one of them was discovered by a Boomerang in the late afternoon, heavily camouflaged under trees. As soon as it was reported, three F4Us of No. 18 Squadron took off to bomb it. It was dark when they reached it, but the reconnaissance pilot marked the target with tracer fire.

On March 5, 1945 during the morning the last tank was attacked by nine Corsairs from No. 18 Squadron. Two of the bombs were almost direct hits and blew off the tank's turret and two doors.

In fact, only one tank was lost in the attacks, likely Type 89B Yi-Go (No. 2) further north, Possibly this tank was dug in as a fixed position. Abandoned during May 1945 when the unit withdrew to Numa Numa.

Wreckage
This tank is located on the west side of the north coast road on the west of Ruri Bay to the southeast of Bonis. The main gun has been missing since at least 1975.

References
Official History Royal New Zealand Air Force, pages 299-300 (Destruction of Japanese Tanks Near Ruri Bay)
Senshi Sosho Vol. 58, Page 164-165
Royal New Zealand Air Force - Northern Bougainville pages 299-300
After The Battle Issue 147 "The Japanese Tanks of Bougainville" by Justin Taylan
Thanks to Akira “Taki” Takizawa for additional information

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Last Updated
October 31, 2022

Type 89
Yi-Go

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