Miyara Bay Shin'yō Boat Tunnels
Ishigaki City, Okinawa Prefecture
Miyara Bay in Ishigakijima, an island about 240 kilometers east of north
Taiwan, has two tunnels from WWII built into a cliff near the bay in order to
hide shin'yō explosive motorboats. The Japanese Navy planned to use these plywood
shin'yō boats, each loaded with 250 kilograms of explosives, in order to make
suicide attacks against American ships if they approached the island.
The two tunnels with entrances about 15 meters apart are about 25 meters in
depth. They are interconnected at the back, so they could be considered as one continuous
tunnel. The left tunnel entrance has a table with incense and other items on it to remember the 68
shin'yō squadron members who lost their lives during the war.
The two tunnels were used by the 38th Shin'yō Special Attack Squadron, which
was formed on January 15, 1945, after shin'yō boat pilots completed training at
Kawatana Torpedo Boat Training School in Nagasaki Prefecture. The squadron had
50 one-man Model 1 shin'yō boats and 188 total members with 8 officers, 50
boat pilots, 35 maintenance workers, 21 headquarters personnel, and 74 base
The main part of the squadron arrived at Ishigakijima on January 28, 1945.
The remaining part of the squadron experienced several delays on its way to
Ishigakijima from Sasebo Naval Base in Nagasaki Prefecture with several stops
along the way. After the sun set on
February 28, 1945, the men went on three motorized sailboats from Kume Island to
Miyakojima, an island about 120 kilometers east of Ishigakijima. Near dawn the
next morning, enemy aircraft attacked the three boats, which burned and sank.
There were 68 members of the 38th Shin'yō Special Attack Squadron on the three
boats who lost their lives. The seven squadron members on the three boats who
survived were reassigned temporarily to a shin'yō squadron on Miyakojima, and
they joined again the 38th Shin'yō Squadron when they arrived finally at
Ishigakijima on August 5.
View of right shin'yō tunnel from entrance
The 23rd Shin'yō Special Attack Squadron with 50 one-man
Model 1 shin'yō boats was also based at Miyara Bay. On December 11, 1944,
this squadron's 184 total members arrived at Ishigakijima after the 50
shin'yō pilots had trained at Kawatana Torpedo Boat Training School in
Nagasaki Prefecture from September 16 to October 15, 1944. The 23rd Shin'yō
Special Attack Squadron was formed officially on October 25, 1944.
View of Miyara Bay from beach near two shin'yō tunnels
There were about 30 tunnels constructed next to Miyara Bay
in order to hide the 23rd Shin'yō Squadron's 50 boats. The squadron ended the
war without having to make a sortie to attack enemy ships, but there were
air attacks day after day. Squadron Commander Lieutenant Makuta, an Etajima
Naval Academy 69th Class graduate, was convicted as a BC Class war criminal
for the killing of an American POW on Ishigakijima. He died in Sugamo Prison
on April 7, 1950.
Officers and shin'yō boat pilots of
38th Shin'yō Special Attack Squadron
The two shin'yō boat tunnels are located just east of the Miyara
River entrance. There are some other shin'yō tunnel remains around Miyara Bay,
but these are not readily accessible.
The historical photographs and information on this web page about the 38th
Attack Squadron are from pages 80-1 (written by former 38th Shin'yō
Squadron Commander Tabii) of the following book:
Shin'yō Association (Shin'yōkai), ed. 1990. Ningen heiki:
Shin'yō tokubetsu kōgekitai (Human weapon: Shin'yō Special Attack
Corps). Shiro Arai, general editor. Volume 2 of 2. Tōkyō: Kokushokankōkai.
The historical information on this web page about the 23rd Shin'yō Special
Attack Squadron is from pages 50-1.