The Japanese homefront - Kawatana, Home of Shinyo and fish-shaped water bomb

by David R. Krigbaum

Editor’s Note: This series is about the Japanese home front in and around Sasebo, Japan during World War II. It is not a condemnation or critique of actions taken by either side during the war but rather a look at the civilian perspective of the war and the still surviving facilities that supported the war effort.

During World War II Japan built the world’s largest battleships and largest submarines, but both those weapons were almost entirely irrelevant compared to the torpedo. Not as flashy as a glorified hotel for admirals or a secret airplane delivery service that failed to deliver, torpedoes were a vital part of Japan’s tactics. It was Type 91 aerial torpedoes that delivered Japan’s declaration of war into the sides of American battleships at Pearl Harbor.
Katashima Torpedo Testing Facility
Many Type 91 aerial torpedoes were built at the Kawatana Naval Arsenal during World War II, though town’s relationship with torpedoes goes back to World War I and the establishment of the Katashima Torpedo Testing Facility in 1918. Unfortunately there is not a lot of information to go on concerning its operational history. In his book, “Japanese Destroyer Captain,” Capt. Tameichi Hara mentions that the old facility had been used for many years, but not recently when he arrived in 1944.
The facility occupied the tip of a peninsula jutting into Omura Bay; but after its final decommissioning, forest has reclaimed much of the area leaving a scattered collection of buildings connected by dirt trails hidden among the trees.
These are the kinds of ruins I love to find. The area is completely open to explore with no fences or artificial barriers and the ruins have just been left as is and are slowly decaying. What’s really fascinating is the lack of information about some of it, leaving me to guess at what a building was used for or how it all functioned in practice.
The pier is cracked and piece by piece succumbing to the water around it. Chunks are missing and blocks are uneven, divots in the deck mark where a rail line once ran and there’s a small raised area where a crane probably was. The red brick tower, covered in a layer of cement is cracked and looks like one day it will come apart.
Near the end of another pier there’s a house-like building on the water that has become an island as the sea has reclaim the length of concrete connecting it to dry land years ago.
The best part of the torpedo facility ruins is a bit of an enigma. A two-story shell of a building, its first floor exterior given the popular rough-stone style exterior the IJN loved in the early twentieth century, but the second floor was left with bare brick. Rails lead inside to a white tile room, except for the parts that have been reclaimed by nature. A tree grows in a pond inside and through the wall is another room with another tree growing through it, but looking at the second story it looks like it could have had a second floor, but it and the stairs are now non-existent.
If it looks familiar, it was used as a setting in the anime movie, “The Beast and the Boy” as well as in a music video.
The immediate area is covered in tall grass that half-conceals fetid pools and an above ground tank filled with green water and leaves, what may be a drainage ditch made of rough stone snakes through the mud and lead to nowhere. Complete enough to see, but not enough to understand, is how it feels.
Venturing into the inland forest path we came across the footprints of buildings and a lone torii gate atop stairs leading higher on the hill. No shrine, just a gate. Atop the hill, after a short yet vigorous hike is the old pointed-face observation platform. The second floor is gone, but someone has left a ladder inside for future visitors to get to enjoy the view from the higher vantage point overlooking Omura Bay. Other visitors left their marks in English and Japanese language graffiti.
We spent about two hours at Katashima. Good exercise and good photos in a historic place make the ruins one of my favorites in Japan.
Starting two years ago, Katashima also began hosting an annual Taketoro Matsuri (Bamboo Lantern Festival), in which candles decorate the ruins and light the paths around the area. Very beautiful and artistic, the festival honors the kamikazes that died in the War. Many were trained in Kawatana.
There is a sign on the premise explaining what the facility was, but in Japanese. So I took a picture and had my Kawatana born-and-raised wife read it to me at home. She took a look at it and made an odd expression. She asked, “What is ‘fish-shaped water bomb’?”
And that’s how I learned what the literal translation of the Kanji for ‘torpedo’ is. Kanji is a funny thing; the characters are less like words and more like abstract pictographs, like drawing a house in the middle of a sentence instead of writing ‘house.’ If you’re unfamiliar with a character or a string of them, you’re out of luck in translating what it really means.
Also, I think we can all agree ‘fish-shaped water bomb’ would be a perfect rock band name.
Looking for information on Katashima I occasionally come across claims it was a Kaiten suicide torpedo training base, which is inaccurate. According to Toshiyuki Matsumoto, Ozushima Kaiten Memorial Museum manager, Kaiten sometimes undertook missions on Sasebo-based submarines and while the nearby Katashima range was utilized for practice, actual pilot training took place at Ozushima and other bases on the Seto Inland Sea. It’s the difference between a dedicated airfield where pilots are taught how to fly and using a convenient airfield for touch-and-go practice. A nearby base was used for various forms of kamikaze training, which we’ll get into later.
If you can only see one place in Kawatana, then Katashima is it, but there are a few other historically relevant sites worth seeing even if their stories and a few bits are all that’s left of them.
Kawatana Naval Arsenal
The Kawatana Naval Arsenal began life as a branch of the Sasebo Naval Arsenal. Its primary purpose was producing Type 91 aerial torpedoes used by the navy’s dive bombers. Located between Sasebo and Omura, home of an aircraft factory and naval air field, it was part of the chain of facilities along Kyushu’s coastline that supported and built war material for the navy.
The original factory was located not far from Kawatana Station, the rail line originally being a valuable means of moving munitions. The size of a large neighborhood, most of the factory is gone but some of it still remains. Driving down along the edge a friend pointed out a rough stone-sided ditch, similar to the one we saw at Katashima, which once marked the factory’s boundary. Four buildings are also still standing, though one is a gutted shell and the others are still being used to some extent.
What makes them stand out from the rest of the normal, post-war housing they hide amongst are their construction materials. One is made of steel-slag bricks, bricks made from the refuse generated in turning iron ore into steel, similar to a few 1930s ammunition magazines on the Sasebo navy base. The other three are made of the red bricks that were popular in the construction of Sasebo navy base. There’s no solid information on what most of these buildings had been, though one has ground level ‘windows’ usually seen in ammunition magazines.
The large and highly visible complex was attacked by U.S. Navy aircraft during the war, necessitating the need for more discreet facilities. In 1944, School children working for the factory were used to dig a series of 16 tunnels into the side of a hill where torpedo production could continue unhindered.
Sui Iseki was such a high school girl employed by the arsenal. After the bombings left them with less need for office girls she was put to work digging the tunnels as well as hacking bamboo and foliage, which was then used to camouflage the entrance. The work was very difficult and a great change of pace for someone used to working a typewriter. The location was a bit of genius on the navy’s part. Located across a rice paddy from a high school, it looks like nothing more than a group of air raid shelters and seeing the tunnels today with no knowledge of what they were (or the ability to read the Japanese sign outside of a tunnel) it’s still easy to make that assumption.
The tunnels are simple yet cleanly finished, not rough-hewn like some late war bunkers such as the Matsushiro Daihonei. The empty shells contain no equipment and cannot be entered, but are only barricaded by chain-link fences so it’s easy to stop by, look in and imagine it buzzing with activity as weapons were built in the cramp space. According to Iseki, it was as unpleasant to work in as it was to build because of the temperature and humidity, though it did provide a safer place to hide when the U.S. Navy fighter-bombers decided to pay Kawatana a visit.
Shinyo Memorial (Kawatana Arashi Butai)
The last point of military interest I visited in Kawatana is the Shinyo Memorial, which stands on the grounds of a school where, to the dismay of its commandant, students learned to pilot seaborne kamikazes.
Originally it was a temporary torpedo boat crew training school and was commissioned on May 1, 1944 with Capt. Tameichi Hara as its commandant. Hara was an expert on torpedoes and a veteran destroyer captain who fought in many of the war’s naval battles such as Java Sea, Guadalcanal and Vella Gulf.
Previously he’d been hand-selected to lead the navy’s primary torpedo boat school at Oppama (in modern Yokosuka) and fulfill a top-secret mission in revolutionizing the navy’s torpedo boat tactics. Discontent with a surplus of unfit students and a lack of viable torpedo boats making such a tactical revolution impossible, he believes his open griping was what got him reassigned to stand up a new torpedo boat school far, far away from Yokosuka
That’s how he found himself in the middle of nowhere, running a decrepit school full of former aviation students crammed into double-maximum occupancy barracks that lacked enough blankets for everyone and facilities he described as ‘ruins.’
Hara was horrified when he learned about the new kamikaze corps. Then he was informed that he would be required to offer seaborne kamikaze courses at his school. For him it went against his principles as he’d always preached the importance of bringing men home alive and he himself was known for bringing destroyers into combat and coming back with no casualties.
The two forms of kamikaze that were taught at Kawatana were Shinyo (“Ocean Shaker”) suicide motor boat crews and Fukuryu (“Crawling Dragon”) suicide frogmen. Of the 400 students at the school when the courses were first offered, half volunteered.
A Shinyo looks like a typical motor boat. Small, made of wood and powered by a six-cylinder Toyota automobile engine, its punch came from a 595-pound powder charge hidden in the bow. A crude set of rocket launchers gave a slight degree of protective firepower to the pilot before hitting his target.
While the concept of using a boat like a manned missile makes a degree of sense, its lack of speed hampered its effectiveness as it was a 23-knot missile that could be seen coming. By contrast, destroyers and most large warships could outrun them by about 10 knots. Their most effective use would be hidden in the countless inlets and caves along Kyushu’s craggy coast where they could sortie out at the last minute and strike landing craft as they approached the beach.
The boats themselves were built at shipyards and automobile factories, the boats in Kawatana came from Nagasaki and the Sasebo Naval Arsenal. A total of 6,200 were built around the country and in a few colonies. Some were used operationally in the Philippines, Iwo Jima and Okinawa, but most were held in reserve for the defense of Japan.
According to Hara’s testimony in his post-War interrogation, it was a myth that suicide boat pilots were given funerals and wore ceremonial robes when sent on a mission. As far as he knew, the pilots were given a banquet and maybe some sake then sent off with, “Go do a good job.”
Fukuryu suicide divers wore lightweight diving gear and the idea was they would walk along the ocean floor and a blow hole in the bottom of a landing craft or ship using a 22 lb. mine strapped to a pole. While there were training casualties, no functional mines were complete before war’s end and no Fukuryu were ever used in combat. The training was dangerous even for expert divers and it was exacerbated by the very poor quality tank oxygen available which often made the students sick.
A total of 1300 Shinyo crewmen and Fukuryu frogmen graduated from Kawatana. Reflecting this change in purpose the school was renamed Kawatana Arashi Butai (“Storm Unit”) in March 1945, though it was still just a training base and not an operational one. According to Iseki, the torpedo factory was involved with making explosives for them.
Ironically, the kamikazes where the only guaranteed survivors of the 400 students that graduated in the first class offering kamikaze training as they were held in reserve for homeland defense against an invasion force that never came. Likewise, none of the frogmen died in combat as there is no evidence they were ever employed.
Though the men were trained to fight to the death and to seek that death in annihilating the enemy, they offered no resistance to occupation when the war ended. American forces took control of the base on Sept. 23, 1945and Hara was surprised at how friendly they were towards him. In turn, the American report stated that the Japanese had been very cooperative.
There’s an odd story to tack to the end of the Kawatana Arashi Butai, and that’s what became of Hara. At the end of his interrogation by the U.S. Marines, he made a request- if he was to be imprisoned he would like to be sent to the U.S. If he was not going to prison, he would like to offer his full services to the U.S. Navy in whatever capacity they saw fit to utilize them. Hara was a survivor, the only early-War destroyer captain still alive, and felt after all the battles he’d gotten through there was no one left in Japan that could share his memories of those battles but he hoped to find others who could in the U.S.
They didn’t take him up on his offer, but he later went on to write his memoir, released in English as “Japanese Destroyer Captain.”
Today only a concrete stump in Ogushi Harbor remains of Hara’s training base. Residential housing has taken over the area and in the middle of it is a small memorial to the Kawatana Shinyo pilots who died in war and training.
To my knowledge no original Shinyo survive, though there are replicas at the Chiran Peace Museum for Kamikaze Pilots and the Yushukan. Also, there’s a guy in Kawatana who built one and occasionally he can be see towing it behind his boat in Omura Bay on special occasions.
All locations discussed in this story are free to visit and don’t really have closing hours, though some of the factory ruins are on private property. The Katashima ruins are also a popular fishing spot for people who don’t mind the possibility of the pier collapsing under them. I also noticed people fishing at the Ozushima Kaiten training center in the Seto Inland Sea, so I guess torpedo facilities are a good indicator of where the good fishing is.

Subscribe to our Stripes Pacific newsletter and receive amazing travel stories, great event info, cultural information, interesting lifestyle articles and more directly in your inbox!

Follow us on social media!

Facebook: Stars and Stripes Pacific
Flipboard: Stars and Stripes Community Sites

Looking to travel while stationed abroad? Check out our other Pacific community sites!
Stripes Japan
Stripes Korea
Stripes Guam

Recommended Content