Failure Knowledge Database / 100 Selected Cases

Seikan Railroad Ferryboat Accident[September 26, 1954 near Nanaehama on Hakodate Gulf, Hokkaido]
by Masayuki Nakao(Tokyo University, Institute of Engineering Innovation)

The Seikan (Hakodate-Aomori) railroad ferryboat, Toyamaru (Photo 1, Fig. 1, 3,899tons) left Hakodate port while Typhoon #15 was approaching. The ferryboat
encountered unexpected size and strength of wind and waves outside the harbor, and it
lowered the anchor in the harbor there. The big waves brought water inside the shipand caused the steam engines to stop. Around 10pm, the ship overturned nearNanaehama. 1,172 people died. This disaster was due to unprecedented speed andstrength of the typhoon as well as improper actions taken against the typhoon.

Photo 1, Toyamaru [2]1Failure Knowledge Database / 100 Selected Cases

Fig. 1 Cross Section of Toyamaru [2]1. Event
The Seikan railroad ferryboat, Toyamaru left Hakodate port while Typhoon #15 wasapproaching. The ship encountered unexpected size and strength of wind and waves
outside the harbor, and it lowered the anchor there. Then big waves brought water inthe ship and caused the steam engine to stop. Around 10 pm, the ship overturnedand struck rocks near Nanaehama and resulted in a disaster with 1,172 people dead.

2. Course（１） On September 26th at 3:00am, typhoon #15 was near Kagoshima City in thesouthern island of Japan. The typhoon traveled through the Japan Sea as itincreased its speed, then moved north at an astonishing speed of 62 miles/hour.
It reached the sea west of Hakodate (Fig. 2) around 8:00 pm on the same day ofthe 26th. Then, it slowed down once, but again increased its power to 956hPa(Fig. 3) and hit Hakodate gulf with gusty winds at the maximum instantaneouswind speed of 57m/sec. Not only the waves from the Japan Sea storm directly
hit the Hakodate Gulf, but gusty winds also came in from the South opening ofthe gulf.
（２） The captain of the Toyamaru, unaware of the Typhoon’s quick move to the northand sudden slowdown, misinterpreted the change of pressure and calm weather
in Hakodate area around 5 pm as the passing of typhoon’s eye.

Actually, theweather at the destination, Aomori was relatively calm; however, there was2

Failure Knowledge Database / 100 Selected Cases

gusty winds of 20m/s outside the breakwater in Hakodate Harbor even though
the winds inside the Hakodate Harbor was only 10m/s from south-south-west.
The captain thought there would not be a problem to voyage since winds would
be coming from the land now and the weather would calm down. Based on thisestimation, he left the pier with 1,220 passengers, 111 crew members and 41
officials: total of 1,331 people at 6:39 pm.
（３） After the ship left the breakwater of the Hakodate Harbor, they encountered
gusty winds of 40m/s and large waves entering Hakodate gulf that had
developed in the Japan Sea. The captain realized that it was impossible tocontinue the voyage, and decided to take one of the common actions for bad
weather, that is, anchoring.

He had the anchor lowered and moved forward ata very low speed to turn the ship to the south.
（４） Stronger winds, with a maximum instantaneous speed of 57m/s, pushed theship to the coast while the ship swayed left and right like a pendulum aroundthe anchor (Fig. 4). The ship, like a typical train carrier, had a train entrance
on the back. Big waves poured water into the ship from the gaps in thisentrance area and the water made its way to the engine room causing theengine to stop.

The ship lost control and crashed into the rocks.

A total of

1,172 people, passengers and crew were killed (Photo 2). The reason why thedeath toll was so high seems because of no one imagining such a sequence ofevents and they were not ready to guide the passengers for evacuation.
At the same time, other ships anchored in Hakodate Gulf went through similar
situations. Four other ships shown below sank and a total of 275 people died(Fig.4).
Hidaka-maru

Commuter cargo

3232 tons (US) Sank

Kitami-maru

Commuter cargo

3228 tons (US) Sank

Tokachi-maru

Commuter cargo

3210 tons (US) Sank

Seikan-maru #11

Commuter cargo

3143 tons (US) Sank

Another ferryboat, Taisetsu-maru also tried to anchor itself in Hakodate Gulf
at first, but the ship left the gulf in order to avoid crashing into other ships
floating in the gusty wind.

Fortunately, this action saved the ship fromsinking.

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Failure Knowledge Database / 100 Selected Cases

Fig. 2, Weather Chart at 4:00 pm on the 26th [2]Fig. 3, Typhoon #15 route (right numbers indicate time, left the pressure(mbr)). [2]4Failure Knowledge Database / 100 Selected Cases

Fig. 4, Movement of ferries in Hakodate Gulf [3]Photo 2, Shipwreck (Nanaehama) [4]5Failure Knowledge Database / 100 Selected Cases

Fig. 5, Seikan Tunnel
3. Cause(1) At that time, the only major transportation connecting the main island of Japanand Hokkaido Island was the Seikan Commuter Ferry, and it had a very important
responsibility of connecting cities of the two islands. This importance of “providinga connection” is likely to have largely affected the captain’s decision that had thesole authority about operation decisions.
(2) The meteorological observation technology of that time was not capable of providing
accurate typhoon information due to the unusually high speed of the typhoon atabout 68 miles/hour. Furthermore, weather around Hakodate area was calm as if
the eye of the typhoon was passing. At the same time, the typhoon was at the sea
west of Hakodate, and rapidly decelerating while increasing its wind speed.
Unexpected wind gusts occurred for the unexpected time, and the damage
increased. The weather conditions of winds and waves were greatly different
between inside and outside of the gulf even near the Hakodate area.
The captain of Toyamaru was an expert and knew all about weather. People evencalled him the “weather chart”. He probably studied information from the radio,pressure gauges, and nearby wind conditions, and judged from his experience that“the typhoon has past and the weather will significantly calm down.”(3) As a measure to cope with gusty winds and big waves, they took the anchoring
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Failure Knowledge Database / 100 Selected Cases

method, that is, to cast an anchor and face the ship to the wind by slowly moving
forward. This method works well for normal storms had problems in exceptionallystrong waves. An anchor stayed in one point at the bottom of the sea and the end of
the rope was tied to the bow of the ship. When the ship slowly moved forward inthis situation, the strong wind swayed it left and right around the anchor. Having
an anchor point while moving up and down produced large tension in the anchor
chain and vigorously shook the boat. Furthermore, the typical railroad ferry
structure (Fig. 1) of having a train entrance at the back of the boat made a way forwater to enter the lower rooms and engine room. The boiler got flooded andeventually the engine stopped. These factors combined, the boat lost control, tilted
by the force of winds and waves, and could not recover.

In the strong winds andwaves such as a typhoon, it is better to pull up the anchor, face the bow towards thewind to avoid waves from hitting the sides, and avoid strong impact from theanchor. When a boat encounters a typhoon in the middle of the ocean, they havebeen using this method to avoid any accidents. After all, Toyamaru should have left
the gulf as Taisetsu-maru did.
4. Immediate Action
In the evening of the 27th, Minister of Transport and Vice president of the Japanese
National Railways (JNR) rushed to Hakodate. Shipwreck investigation agency started
investigating the cause of the accident.
On the 28th, The House of Representatives Transportation Committee called the head ofJNR in and inquired their measures.
Since the captain of the ferryboat died, the committee collected information from thesecond mate, highest in rank among the survived crew.

He said “We were scheduled

to depart at 2:50 pm, but we delay the departure due to rough waves. At about 5:30, theweather got better. There was a storm warning, but we did not get any damage fromTyphoon #12, we did not expect the weather to get that bad. We departed at 6:40, andimmediately after the departure, we encountered winds of 32m/s. When we went out of
the gulf, the weather was terrible, so we headed back. We put the anchor down outside
the breakwater, but we could not fix the anchor. We ran the engine at full speed against
the wind, but both engines stopped around 10 o’clock, the ship was beaten by the roughwaves and hit rocks at 10:26.

The ship turned over about 7 to 8 minutes after that.

Passengers with life jackets immediately jumped into the sea.

Our estimate of thetyphoon’s behavior was wrong.”
5. Countermeasure(1) The ship operation improved by adding the land station to the decision making
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Failure Knowledge Database / 100 Selected Cases

instead of giving the captain the sole responsibility. In addition, a system wasinstalled to automatically stop operations including railways when weather
condition exceeds certain parameters.
(2) Action guidelines in case of typhoons changed to moving toward the winds while
lifting the anchors and letting the boat float while avoiding getting hit from thesides.

(This method is effective in avoiding unendurable impacts from anchors.

This method has helped ships escape from the middle of typhoons.)(3) Modified the structure of the ferry body as follows:
Train entrance doors at stern of the ferry were modified to have water proof①structures②

Turnover prevention system on the ship body was improved.

③

Coal turbine systems was replaced by diesel engines.

(4) In order to replace the railroad ferryboats, they started planning the Seikan tunnel
as the transportation system between Aomori and Hakodate.
6. Summary
Although a typhoon with unbelievable strength was approaching to Hakodate, thecaptain who was responsible for the operation assumed the winds would get weakerand decided to take off with the passengers. Soon after they started, they encountered
gusts of winds. They immediately anchored and stayed within the gulf, but the water
entered the ship and caused the ship a disaster of hitting rocks and turning over.
7. Knowledge（１） No matter how prominent a person is, the Mother Nature may exceed hisestimation or judgment. If there is any chance of danger, safety caution musttake place. In this case, even if the captain had decided not to take thepassengers, the ship would have anchored itself and had sunk in the gulf withthe captain and the crew, but at least lives of the passengers would have beensaved.
（２） Commonly used actions (such as anchor and stay method in this case) should be
used under certain circumstances. If the conditions were more severe thanoriginally expected, commonly used actions should have been reviewed.

It isessential to carry out simulations for more severe situations.
8. Background
Seikan (Aomori-Hakodate) railroad ferryboat, Toyamaru was placed in service in1947 to provide a way of commuting between Aomori and Hakodate ports. It was partof the project to increase the number of commuting ships between Aomori andHakodate that had been almost destroyed during the war. In 1950, it was the firstcargo-passenger ship in Japan to have the latest technology and radar installed. At8Failure Knowledge Database / 100 Selected Cases

that time, Seikan Tunnel did not exist. The ferry was the only means to connect themain island of Japan (Honshu) and Hokkaido; its mission was important.
The weather observation technique at the time, differently from today’s satellite
technology, were simple and inaccurate in terms of locating the typhoon, telling its
strength, speed and direction.
9. Sequel
Since this accident, preparation for the Seikan (Aomori-Hakodate) tunnel project
accelerated as Fig. 5 shows.

In the evening of March 13, 1988, the last railroad

ferryboats left Hakodate and Aomori port and closed the 80 years of Seikan railroad
ferryboat history.

That same morning, Seikan tunnel started the operation. SeikanTunnel kept the lead tunnel next to the main tunnel, so upon a fire, people can go to thelead tunnel through the number of side tunnels for evacuation. Another underwatertunnel, the tunnel under the Strait of Dover also has a lead tunnel between two main
single lined tunnels for evacuation.
<References>[1]

ZOKU-ZOKU JISSAI NO SEKKEI (Practical Design Vol.3)
by Yotaro Hatamura and Jissai no Sekkei Society, Published by Nikkan Kogyo
Shinbun LTD. (1996)[2]

Why Toyamaru Sunk by Junichiro Uemae, Published by Bungeishunshu (1983)[3]

Seikan Railroad Ferryboat by Koshiro Sakamoto, published by Asahi Evening News(1983)[4]

Truth of Sunken Toyamaru after 32 years by Keiki Fukui, published by Shikai
Shobo (1986)

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