Roy Kaiser shared some interesting information about the bombs that were dropped on Tokyo in Part 1 of Reflections on Unexploded WWII Bombs in Japan and today he talks about three different disposals that he participated in as a member of the Explosive Ordnance Disposal (EOD) team based out of Ikego Army Ammunition Depot in Kanagawa Prefecture.

Tanashi, Tokyo, January 1969

A 500lb HE bomb was found with a M123 chemical long delay anti-withdrawal fuse. The Japanese Ground Self Defense Force (JGSDF) asked the asked the Explosive Ordnance Disposal (EOD) unit from Ikego Army Ammunition Depot to take on the job of rendering the bomb safe. It was determined that blowing up the bomb in place with a full scale detonation was not the best way to go because the bomb was located next to houses, a railway station and a hospital.

The commanding officer, Lt Lanier, recommended that a sand bag barricade be built around the bomb to reduce damage to the area in the event of a full-scale detonation or contain the damage that would result from a partial detonation. It took 60 men from JGSDF, 10 hours to fill 8,000 sand bags and erect the barricade based on the specifications of the American EOD team. Roy said “I was amazed when I saw the sand bag barricade. It was big!”

The Assistant EOD Supervisor of the 97th SFC Albertson, a WWII EOD veteran who had retired and returned to active service, mentioned that sometimes the personnel fusing these bombs were in a hurry and failed to insert the locking pin in the adapter booster. This was a long shot but the team though it was worth investigating. Lt, Lanier and Roy climbed over the sand bag barricade and studied the bomb for a few moments. It was apparent that the bomb had been moved at some point and had not detonated so they decided to see if there was a locking pin. They applied gentle pressure to adapter booster in a counter clockwise direction, expecting to meet the resistance of the locking pin, but there was no resistance. It turned out that SFC Albertson’s long shot was right, there was no locking pin, and the adapter booster with fuse came right out of the bomb. It took just a few minutes render this 500 lb bomb safe!

Inokashira Park, Tokyo, 1969

Shortly after disposing of the Tanashi bomb the EOD team was told of another UXB that was in the process of being excavated in Inokashira Park about 20 minutes by train from Tokyo’s Shinjuku Station. It became a concern after another bomb in the park had detonated for no apparent reason. Excavation of the bomb was complicated by the fact that the site kept flooding with water. The JGSDF engineers excavated and 15 foot hole, reinforced it with metal pipes and set up a system to pump water from the excavation site.

A few days later the area was evacuated and the EOD team went to work. First they discovered that someone had sawed off the arming stem adapter plug, which is one of the ways the EOD team identifies the type of bomb they are dealing with. Roy tells us that this and the jackhammers that were used around the bomb were “bad things to do” and says that it was fortunate that these efforts did not cause the bomb to detonate. He went on to say that “Since the bomb had been subject to so much rough treatment during the excavation without detonating, and the successful experience with the Tanashi bomb we thought a procedure from a WWII disposal manual was worth a try.”

Roy was at the control point that had been set up some distance from the bomb and was in constant contact with the technicians at the bombsite via wired communications. This time the adapter booster was locked in and it took about 2 hours, several modifications of tools and several trips back and forth between the control point and the bomb site before the adapter booster and fuse were successfully removed and separated from the bomb. The adapter booster, still containing the fuse was well sand bagged and transported to Ikego Army Ammunition Depot where the fuse was remotely removed from the adapter booster and the adapter booster was destroyed. A few days later, while stored under a sand bag, the fuse functioned, setting off the detonator.

The Bomb that Did a U-turn

The third UXB disposal that Roy participated in was pretty much routine and occurred some time prior to the incidents above. The only notable thing about this disposal for Roy was that the shaft dug to access the bomb went down and then off to one side in order to expose the tail of the bomb for disposal. The bomb had penetrated the ground, somehow made a U-turn, and was pointed toward the surface!

The cost to dispose of the Inokashira Park bomb was $38,892 in 1969 which is over $220 thousand US dollars today and Roy explains how today the decision to dispose of a bomb that has survived more than 50 years of earthquake activity, surrounding construction and the daily rumblings of train and automobile traffic boils down to economic practicality and requires the careful consideration of the cost involved in the excavation and disposal versus the risk that the bomb will detonate. Roy says that “Let sleeping dogs lie” is often the chosen approach until, for one reason or another, the unexploded ordinance becomes a present day problem as it did with the Chofu bomb that was the inspiration for the Unexploded WWII Bombs In Japan- How Many Are Out There? article.

Roy doesn’t believe that there should be a excessive concern surrounding unexploded bombs that still remain in Japan and says that the JGSDF EOD teams have proven their skill and professionalism in rendering safe and disposing of unexploded ordinance time and time again. He goes on to remind us that the Japanese are not alone, Britain and Germany also have the same problem resulting from the bombings that they were subject to during WWII. Recent conflicts have brought a modern era UXO problem of cluster bombs and land mines to several other countries. Roy considers his 15 year career in EOD a “walk in the park” when compared to exceedingly more dangerous environment faced today by EOD personnel in Vietnam, Afghanistan an Iraq where they are often shot at, targeted by a roadside bombs, and have secondary bombs set up to detonate in the vicinity while the EOD team is responding to an incident. He says that EOD personnel have become prime targets and their job is much more difficult and stressful that when he did it back in 1969.

I would personally like to thank Roy for sharing his insights into the fascinating subject and tip my hat to all of the current and retired EOD technicians out there, in Japan and elsewhere, whose dangerous work allows all of us to go on with our daily lives safely.

Lastly, Roy reminds us all that if we ever come across an UXB, we should consider it armed and very dangerous. Do not disturb it and call local authorities immediately.

(Images courtesy of Roy Kaiser)

The recent 7:10 to Tokyo article, Unexploded WWII Bombs In Japan- How Many Are Out There?, provoked some interesting responses but it came as a bit of a surprise to hear from someone who was actually on the ground in Japan disposing of these remnants from WWII. Roy Kaiser took an interest this article and provided a lot of food for thought in his well-researched comments. Roy had a fifteen-year career in Explosive Ordnance Disposal (EOD) for the US Army and spent three of those years (1967-1970) at Ikego Army Ammunition Depot in Kanagawa Prefecture. He has generously agreed to share some insights on how bombs work, how they are disposed of and has provided some interesting newspaper clippings from the time. Roy retired in 1976, after 24 years of service. He often recalls the time he served with the 97th and fondly remembers the great guys he served with.

The 97th Explosive Ordnance Disposal (EOD) was the last US Army Explosive Ordnance unit stationed in Japan (deactivated in 1970) and was based in Zushi City, about 40 kilometers (25 miles) outside of Tokyo. Roy was assigned to this unit from 1967 - 1970 and recalls participating in the disposal of three unexploded bombs (UXB) during that period. In his comments on Unexploded WWII Bombs In Japan- How Many Are Out There?, he states that between November 1, 1944 and August 15, 1945 American B29 Superfortresses dropped more than 11,000 bombs, weighing 500 pounds or more, on Tokyo alone, destroying 51% of what is now the worlds largest city. Historically 5-20% of military high explosive munitions fail to function as intended (duds). Given those failure rates somewhere between 500 and 2,200 unexploded bombs would have been left behind after WWII.

So why didn’t theses bombs detonate? Roy explains that the general purpose, high explosive, bombs that were dropped on Japan had three main types of fuses resulting in detonation on impact (nose and tail impact inertia fuse), detonation after surface penetration (tail impact inertia fuse), or delayed action detonation up to 144 hours after impact (tail fuse).

When a bomb is dropped an arming wire is normally withdrawn from the arming vane, which looks like a little windmill, and the vane then rotates a rod that arms the fuse which causes the bomb to detonate. If the bomb came out of the plane without the arming wires being extracted the bomb would impact the ground without detonating and would leave a penetration hole rather than an explosion crater. Another possibility is that the bomb’s firing pin could fail to strike the detonator or get hung up by some type of obstruction, in which case the bomb could detonate with the least disturbance. To further complicate matters, most bombs had an anti-withdrawal feature that prevents the adapter booster and fuse from being unscrewed from the bomb by a locking pin. If an attempt was made remove this portion of the bomb, the licking pin would activate the fuse and the bomb would detonate. (Bomb diagram)

Tokyo’s Real Boom Town article circa 1967

After a bombing raid, Japanese civil defense officials would scour the area bombed to look for impact craters. US UXB reconnaissance procedures would include probing the penetration hole with a long non-magnetic rod to determine the trajectory of the bomb and its final resting place. The location of the bombs would then be recorded on a map similar to the one that you see below.

Map of UXB locations in what appears to be Yurakucho, 1 Chome

Once the unexploded ordnance is located, a variety of different disposal methods are available to the EOD teams. The decision is often a difficult one as there is a need to balance risk to the EOD team with magnitude of the damage that would result if the unexploded bomb were to detonate. The options include remote on-site detonation, removal and transport to a remote destination for disarming and/or detonation, or a hands-on disarming of the ordnance on-site. The latter method carries the most risk for the EOD team and is only utilized to protect lives, very important property, materials, or facilities. The safest way to dispose of UXB is to evacuate the area, take measures to protect against blast damage, and then detonate the bomb in place. This option is usually not available in densely populated areas like Tokyo.

(Images courtesy of Roy Kaiser)

Part 2 of this article can be found here

On March 27th an unexploded bomb was found in the Tokyo suburb of Chofu by construction crews. It is suspected that the B-29 bomber carrying the ordinance collided with a Japanese Hien fighter plane on April 7, 1945 before it had an opportunity to deliver it’s payload. A 63 year old resident of the area was a junior high school student at that time and sketched the crash in his diary and returned the following day to sketch what remained of the B-29 bomber. Researchers compared the sketch with the flight records of the Hien fighter that crashed that day and confirmed the connection.

Although the bomb was located on March 27th it was not diffused until this past Saturday, May 18th. The one-ton U.S. made bomb was buried 3.25 meters underground and is about 1.8 meters long with a 60 centimeters diameter. Like me, you may have though why did it take almost two months for the bomb to be diffused and what were the potential risk to the residents of the area should it explode?

The Daily Yomiuri reported that “after the bomb was discovered, the Self-Defense Forces took swift measures to secure the area and a security company is monitoring the bomb around the clock. ” The city issued an order which resulted in the evacuation of about 16,000 people from approximately 8,000 households within 500 meters of the bomb to leave their homes on May 18 for the duration of the disposal work.

So for almost two months 160,000 residents were living, working and playing around a ‘heavily secured’ 1-ton bomb that if it were to explode above ground would send shrapnel and debris over a two kilometer area! I’m not a scientist but these numbers concern me. The evacuation area was 500 meters in diameter when the potential area of damage could have been a large as 2 kilometers. Would the 3.35 meters of dirt covering the bomb reduce it’s impact by a quarter? What if there had been a large earthquake between March 27th and May 18th? Could the rumbling have set off the bomb?

This is not an isolated incident. Here are some other recent cases:

• About 10,000 residents of Higashi-Nada Ward, Kobe, were issued with an evacuation order in March 2007.
• A 300 meter area of Osaka was evacuated in April to dispose of a bomb found by construction workers.. It was the 97th one-ton bomb discovered and defused in Osaka since the end of World War II in 1945.
• In fiscal 2004 alone, Defense Agency bomb squads defused 146 tons of explosives reported in some 2,600 cases. Anywhere from 1,600 to more than 3,000 cases are handled each year.

Between 1939 and 1945 the Allies dropped 3.4 million tons of bombs, an average of about 27,700 tons of bombs each month. It is hard to determine exactly how many tons of bombs were dropped on Japan during WWII but some estimate that up to 30% of the bombs dropped did not explode on impact. How many more unexploded WWII era bombs are still out there undiscovered? What is the danger to the public? Should the time from discovery to diffusion be less than two months?

I don’t have the answers to the first two questions but I know for sure that if I found a bomb in my back yard I would hope that it wouldn’t take the government two months to remove it!

Tokyo unexploded bomb news footage

Sources:
Mainichi Daily News, Man’s 63-year-old sketch pinpoints dud WWII bomb
Daily Yomiuri, Tokyo area to be evacuated for WWII bomb defusal
China Daily, World War II bomb clearance may need 150 years
World War 2. info, World War 2 Facts
Japan Times, Remnants of war still buried in Japan

The story continues: read here

From the Karakuri doll to an eco-friendly robot that improves the efficiency of today’s assembly lines and factories and from the Makyoh or “Magic Mirror” that protected Christians from persecution to a machine that ensures the quality of today’s silicon chips. These are just two examples of modern technology based on ancient art forms perfected by the Japanese.

Karakuri Dolls to Robots
Back in the days of Edo the Japanese were fascinated by the ‘magical’ movements of Karakuri Dolls. In fact the term karakuri is actually much newer than the technology. The term was used in mechanical engineering in the Edo Period (1603-1868) to describe strange movements. It is said to be a variation of the word kairai which refers to a marionette, and denotes a person who acts as ordered by others.

The exposure to Karakuri technology was at first limited to the nobility of Japan and most everyday Japanese were not exposed to Karakuri until the arrival of wind up clocks via Protugese trading ships. Konoe Takeda, a clockmaker during the Edo Period, was fascinated by this clock that ran automatically and took it upon himself to figure out how it worked. Once Takeda decoded the internal workings of the clock he adapted the technology for use as entertainment in the form of animated puppets used in a drama called ningyo-johruri. The next step was the creation of the karakuri doll, the first of which was designed to serve tea.

“Setting the tea cup on the tray makes the doll move, and it stops when the tea cup is removed. If the cup is replaced, the doll swivels around and returns to its original position.”

Karakuri dolls were the first automata in Japan and are the ancestors of today’s robots.
Since it was first published in 1798, the Karakuri-zui (Illistrated Compilation of Mechanism-art) by Hosokawa Hanzo Yorinao, has laid the groundwork for such items at the Chahakobi Ningyo (humanoid robot) created by Professor Shoji Tatsukawa of Waseda Univertisty, and Sony’s Aibo, a robotic dog that is said to be a substitute for the real thing.

By far the most practical use of Karakuri mechanical technology is the creation of robots that utilize the combination of springs and gears first seen in Karakuri dolls. Today’s Karakuri robots were said to have been pioneered for use on the Toyota assembly line by its founder, Sakichi Toyoda, a Karakuri master. These mechanical karakuri robots are environmentally friendly, they don’t use fossil fuels or electricity, and create efficiencies that speed up many modern day assembly lines. They can be linked directly back to the work of Konoe Takeda and his predecessors who combined technologies of east and west to create Karakuri, a unique Japanese innovation.

The “Magic Mirror” to Silicon Chip Quality Control
The Makyoh (Japanese for “magic mirror”) is an ancient art that can be traced back to the Chinese Han Dynasty (206 BC — 24 AD). The craftsmanship used to make these “magic mirrors” was honed in Kyoto, Japan to help Christians worship at a time when doing so was a crime punishable by death.
A Makyoh is created be etching an image on a metal surface and then sanding it down and covering it with a mercury amalgam that is then highly polished until no surface imperfections can be seen by the naked eye. It take many years of training and a high degree of skill to successfully create a makyoh. If you gaze into the front of the mirror you will see a reflection of yourself but when held up to a light the etched image can be projected onto a surface. It is said that many of theses mirrors were created with the image of Jesus Christ so that Christians of the time could worship without fear of punishment or death.
The skills required to make a makyoh utilized an understanding of photo optics that is employed today to verify the quality of Silicon chips used in most modern day electronics. Silicon chips must be perfectly smooth in order to perform correctly and a modern day “magic mirror” is used to test the smoothness and identify and imperfections.

“The mirror-like surface under test is illuminated by a parallel light beam, and the reflected beam is intersected by a screen. If the surface is perfectly flat, a uniform light spot appears on the screen. If the surface possesses deviations from the flatness, these deviations disturb the homogeneity of the reflected beam, and an image that is related somehow to the surface morphology appears on the screen (see figure on the right). The main advantages of the method, as compared to other optical methods, are its simplicity, inexpensiveness, real-time operation and high sensitivity.”

Today, the car you drive was manufactured more efficiently with the help of karakuri technology and the silicon chips in your computer, your cell phone and many other items that we generally take for granted on a daily basis, were deemed operational utilizing makyoh technology. It is interesting how these ancient crafts helped to lay the foundation for the creation of some of the ‘great innovations’ or out time. Where will they take us next?

Cool video of a karakuri doll in action - check it out! 

Karakuri Sources: Karakuriya.com and karakuri.info

Makyoh Sources: Makyoh topography and Grand Illusions - Magic Mirrors

GOMI is an acronym for the Garbage Organization & Monitoring Institution and you can get your degree right here! You finally made it to Japan and you thought that you were well prepared - you’ve mastered the currency conversion, you’ve memorized Japanese for Busy People and you’ve read all the tips and tricks that you could find about living in Japan. But, there is one more thing that you need to do to make your life in Japan a lot easier; In order to be accepted by your neighbors and avoid receiving nasty notes in your mailbox from your landlord (that you can’t read) you need to master GOMI.

I’d wager you think that recycling is a good thing and I’d even bet that you think that you already know how to do it. Think again, dealing with your garbage (gomi) in Japan is no easy task! Even if you come from a place like California where recycling is commonplace, you will find that the Japanese take recycling to a whole new level and that’s where GOMI comes in. It is the mission of the organization to educate you on the proper sorting and disposal of your trash and to ensure the survival of the GOMI Guru.

Evidence of recycling is apparent everywhere in Japan. Apartment buildings have whole rooms dedicated to it and almost every convenience store, fast food restaurant and train platform has at least two receptacles for trash conveniently placed for your educated use. But do you know how to use these facilities correctly? Study hard and you may be one of the lucky few who can attain the status of a GOMI Guru.

GOMI Level 1 - Three Categories

The Tokyo International Communications Committee offers up a handy, if somewhat overwhelming, guide to trash collection in the Tokyo metropolitan area where they describe the three main categories into which you need to separate your trash as follows:

1. Combustible trash (moeru gomi), which includes kitchen garbage, clothes and paper products.
2. Non-combustible trash (moenai gomi), which includes plastics, metals and dishes.
3. Recyclable Trash (shigen gomi)which includes items such as PET bottles, newspaper, cardboard and batteries.

Each of these categories of gomi are collected on a different day and need to be placed in the appropriate bag designated by your local community. These bags can be purchased at your local supermarket or convenience store.

That’s not so bad, you say - I can do that in my sleep. Congratulations, you can claim GOMI 1 proficiency!

GOMI Level 2 - Segregation of Recyclable Trash

You need to further separate the recyclable trash into the various receptacles provided at your apartment complex (even your local McDonald’s will be in on the act). This is not so hard if the collection day is close at hand and most of the bins have something in them. Place the cans with the cans, the plastic bottles with the other bottles etc., but where do you put that battery, what about that burnt out light bulb?

I challenge you to do your recycling the day after the pick-up. If you can correctly segregate your recyclable trash then, you can claim GOMI 2 proficiency!

GOMI Level 3 - Oversized Garbage

Trash is classified as oversized (sodai gomi) if it is larger than 30 centimeters in width . This classification includes such things as bicycles and furniture. There is usually a fee and you will most likely need to make an appointment for the pick up of sodai gomi. This fee and the rules surrounding the pick up of such items varies from city to city, even within Tokyo. A further set of rules applies to appliances like televisions and refrigerators and yet another set for computers and other electronics.

If you can arrange for the proper disposal of that undersized chair that got broken because no normal sized foreigner was ever meant to sit in it then you can claim GOMI 3 proficiency!

GOMI GURU

Let me warn you: if you want to become a GOMI Guru, you will have to make some drastic changes to your lifestyle. To become a GOMI Guru you will need to master the art of the furoshiki, and you can never again eat with disposable chopsticks!

I have not yet had the honor of meeting a GOMI Guru as I think that this species is now endangered and has been since the invention of disposable chopsticks. Authorities are working diligently to ensure the survival of the species.

The Garbage Organization & Monitoring Institution thanks you for your time today and is doing a survey to determine the state of GOMI in Japan. Please let them know your level of GOMI proficiency. Your participation in this unscientific poll for this imaginary institution is appreciated.

Note: There is a poll embedded within this post, please visit the site to participate in this post’s poll.

Whether you are visiting or living in Japan it won’t take long for you to realize that there is a fascination with the English language here. You will actually see a lot of English on advertising, clothing and stationery in Japan but they don’t always get it right. It’s a good thing that the advertising for this prominent pizza company put a picture behind the headline otherwise it may have taken me a while to figure out what “mashrooms” were.

Most Japanese students complete six years of mandatory English classes during the course of their education. The majority of this education is focused on reading and writing with relatively little practice on the oral aspect of the language or, apparently, the grammar and spelling component. Below are some examples of some uses of the English language in my neighborhood.

If I had a toothache I would definitely want to go to the clinic below and not a contaminated one.

But if I had an itch and I needed some medicine I’m not sure that I would wear a t-shirt for “It’s No. 1 Brand of Anti Itching Medicine” that claims to “Attack for Itching!!!!!!!!”. Wearing this t-shirt probably wouldn’t get you many dates back home or anywhere for that matter.

The t-shirt below boasts that the “Japan Character” is “dedicated to those with an indibidual personality like yours.” I like to think that I am a unique individual but I’m not sure if I want to be that indibidual?

If you don’t believe me yet just check out the instructions and warnings printed on packages in the store. I purchased a lighter the other day and here was the first line of the ‘directions’:

“It is only for the ignition of the cigarette. Please never do the usage that causes other fire and burn.”

Granted the lighters were made in China so maybe this was a Chinese translation into Japanese and then on to English. But it was successful as I got the point even though the wording was a little off.

I could go on and on but I will end by telling you about the young man on a train platform that caught my eye. He was sloppily dressed with spiky hair and a messenger bag slung over his shoulder with the words “Good for Nothing” printed boldly on the side. I don’t know about you but I’m pretty sure that I don’t know anyone in an English speaking country that would carry that bag around.

Maybe he would like some mashroooms on his pizza?