Failure Knowledge Database / 100 Selected Cases

Multiple train collision at Mikawashima
May 3, 1962 at Mikawashima on the Joban line
Masayuki Nakao (Institute of Engineering Innovation, School of Engineering, The University of Tokyo)
A multiple train collision occurred 350m east of the M ikawashima Station of JNR, involving a freight train on
the outbound Joban freight line and passenger trains on the outbound and the inbound Joban lines. The primarycauses were the train operators’ red light running and a delay in the stationmaster’s accident notification. Afterthe initial collision between two trains, 160 passengers were killed and 296 were injured by the accident. Manyof themwere passengers o f t he ou tbound-train who wer e w alking on th e in bound line to wards theMikawashima Station after getti ng out of the train through doors opened using emergency handles. They wererun over by an incoming train on the inbound Joban line.
1. Event
A multiple train collision occurred 350m east of the Mikawashima Station of JNR, involving a freight train
on the outbound Joban freight li ne and passenger trai ns o n t he outbound and inbound J oban lin es. 160
passengers were killed and 296 were injured in the accident.
2. Course (Figure 1 and 2)
The first collision: At 21:36, a freigh t trai n 28 7 fr om the T ahashi Swi tchyard bou nd for Mito on theoutbound Joban freight line was traveling to join the main line at Mikawashima Station. The freight train
operator missed the red s ignal at t he main l ine (th e fr eight line was to w ait for 2117H train on the main
outbound passenger line to leave the station). At 21:36:30, the freight train broke through onto the safetysiding. The signal connected to th e safety siding activated the fail-safe device, preventing the freight train
from entering into th e main l ine, ho wever, the loco and firs t t anker wago n d erailed t o b lock t he main
outbound passenger line.
The second collision: The 7-car passenger train 2117H bound for Toride from the Ueno Station departed
the Mikawashima Station at 21:36, 4 minutes behind schedule. At 21:36:40, the passenger train, which wastraveling at 40km/h at that time, struck the derailed freighter. The first t wo cars derailed and blocked th e
main inbou nd pass enger lin e. The safety s iding prev ented a d evastating colli sion, result ed i n o nly 25
injuries. Passengers of th e 2 117H opened doo rs u sing em ergency handles and st arted walkin g on t heinbound line towards the Mikawashima Station. The Mikawashima East Signal Station located 100m fromthe accident site had 2 operators, but they were too busy confirming and reporting to their manager about
the accident to stop the departure of the next passenger train.
The third collision: 5 minutes and 50 seconds after the second collision, the passenger train 2000H boundfor Ueno arrived on the main inbound passenger line, ran over people escaping from the accident site andcollided with the detailed 2117H. Its first car was smashed and its second cars through the fourth derailed,1Failure Knowledge Database / 100 Selected Cases
resulting in a to tal o f 160 lost l ives a nd 29 6 i njuries. T his third collision b rought d evastation t o theaccident.

Figure 1. Mikawashima Station on the Joban Line [1](The passenger line and the freight line join the main line at the Mikawashima Station.)2

Failure Knowledge Database / 100 Selected Cases
Figure 2. Collision at Mikawashima: Sequence of Events [1]3. Cause
The direct cause was the freight train operators’ missing of a red signal. Although an automatic train stop
device was not available at that time to stop the train when the operators missed a signal, the safety siding
functioned properly as a fa il-safe sy stem for pr eventing a dev astating col lision. I t pr evented the fr eighttrain from entering onto the main line.
However, the freight train was traveling too fast to stop on the safety siding. It derailed to block t he down
passenger line. The collision of the outbound train 2117H with the freight train occurred 10 seconds after
the freight t rain colli sion. Althou gh i t wa s a lmost impossible for the 2117H to avoid the acci dent, theaccident itself was very small in scale injuring only 25 people. The safety siding saved lives and minimized
damage caused by the accident.
The impact of the a ccident wor sened when p assengers, witho ut being i nstructed by the tr ain operators,opened doors usi ng emer gency h andles that w ere ins talled in resp onse to the Saku ragi-cho A ccident o f
1951 (passengers were trapped in the train cars and unable to escape from the train fire), and got off thetrain onto the railway track.
The d elay i n stopping the next inboun

d train 2 000H multiplied the damage t o the accident. T hestationmaster could have taken some action to s top departure of th e 2 000H in 5 m inutes an d 5 seconds.
However, the relay of information taken by the stationmaster and operators led to delay as shown in Figure
3, resulting in the multiple train collision and many casualties.

Figure 3. Communication Delay [1]4. Immediate Action
While it was essential to investigate the direct cause of this accident, a lot to considerations must be given
to adequate immediate actions that should have been taken after the first collision occurred.
Inadequate responses to the accident, for exa mple the passengers go t off the tr ain onto the r ailway tr ack3Failure Knowledge Database / 100 Selected Cases
without instruction from the train operator s and the stationmaster failed to notify the st ation up the line assoon as the accident happened, led to the devastating accident.
5. Countermeasure(1) An automatic train stop device (ATS) had been installed on all lines of the Japanese National Railways.
The ATS activates the emergency brake when the train passes through a red signal.
(2) The railway’s operation policy changed from “do not stop trains unless absolutely necessary” to “stoptrains as soon as an accident happens regardless of its scale”. To increase safety further, a tr ain radiosystem was installed to enable direct communication between train operators and the center.
6. Summary
Considering the signaling sy stem at that time, it is understandable that the o utbound passenger train wasunable to avoid co llision with th e fr eight train der ailed missing a r ed sig nal. Th e multiple-train collision
was d ue t o the r ailway cr ew’s f ailure in stop ping de parture of th e next inb ound train 2000H. The t hirdcollision o ccurred 5+ m inutes after th e s econd co llision, wh ich s hould h ave g iven enou gh time fo r therailway crew to stop the next train.
The safety plan was ineffective be cause it di d not a uthorize th e signal station op erators to s top trains attheir own discretion. The railway crew training was also insufficient.
7. Knowledge
When an accident happens, stop traffic first and then determine the accident scale.
Operators should be adequately trained for emergency procedures and authorized to stop operation of theirdevices at their own discretion.
In response to this Mikawashima accident, the railway implemented an operational policy of “stop trains assoon a s an acc ident happens re gardless of it s sca le”. However, 10 years later in 1972, this pol icy added
devastation to the damage in the train fire in the Hokuriku Tunnel (a passenger train made an emergency
stop in the tunnel). Required emergency procedures differ depending on the accident’s circumstances andan instruction manual cannot cover everything. Training must raise the safety consciousness of operators sothat they can always give reasoned judgment even under unexpected circumstances.
8. BackgroundOn October 26 , 1943 at around 18:40, a similar multiple train collision occurred near the Tsuchiura SouthSignal B ox at the T suchiura S tation on the Jo ban l ine. Howev er, ther e was little r eport on the ac cident
because of the ti me ( during th e war). The Mikawashima acci dent ( the t hird collision in p articular) ma y
have been preven ted, i f imp rovements had been made to the safety plan in response t o the T suchiuraaccident.
The emergency door handles that brought a problem in this accident were installed after the train fire at the4Failure Knowledge Database / 100 Selected Cases
Sakuragi-cho Station on the Keihin-Tohoku line, which claimed many lives in 1951. At the Sakuragi-choStation, the passenger train MOHA-63 touched a sagging overhead wire and sparks caused a disastrous fire.
Among the passengers trapped in the train cars, 106 were killed and 92 were injured. The operators wereunable to open doors because of short-circuits, and the window structures did not permit evacuation ( themiddle panel of the three-panel window was fixed to the frame).
Some may argue that this improvement (emergency door handles) invited a large number of casualties, but
we need to always remember the basic fact, that is, “railway tracks are for trains to run on, not for people
walking on them”.
References[1] Yotaro Hat amura (Edit or), Jissai-no Sekkei (Practical Design) Re search Foundat ion (1996) Zoku-Zoku
Jissai-no Sekkei (Practical Design III), The Nikkan Kogyo Shimbun, LTD.

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