Why Did Three Trains Collide In Balasore?

Were the railway systems in place and working? Or was there any meddling at the signalling and interlocking points?

Out of The Loop

The best way to dispel rumours of sabo­tage in the horrifying train accident in Balasore, Odisha—involving two passenger trains and one goods train on June 2—is to carefully study the real cause of the mishap that claimed the lives of about 290 innocent persons. According to the preliminary joint inspection report of the Indian Railways: “Signal was given and taken off for the up main line for train number 12941 (Coromandel Express), but the train entered into the loop line and derailed.” It dashed into the stationary goods train. Meanwhile, train number 12864 (Bengaluru-Howrah Superfast Express) passed through the down main line and two of its coaches “derailed and capsized”. Railway Minister Ashwini Vaishnaw has said the mistake may have taken place in point machines and electronic interlocking.

Railway signalling systems work on a fail-safe design. If any failure occurs, it will automatically cause the train to stop. Then the entire system is checked manually by someone responsible and as per railway manuals, that person has to sign a paper to allow the train to start again. One of the key components of the signalling system is interlocking, which means that if a signal is given for a particular route then that route cannot remain occupied.

All logics of signalling and every signalling for every route are tested at least 10 times during various stages of drawing, software, hardware, installation and commissioning. It is simply a robust way of doing work, says an official. But the number of checks are so many that projects often get delayed due to signalling works not being ready—either due to testing or due to documentation at each stage.

But field staff has often been found to bypass some parts of the vital signalling system, thereby giving the wrong signal. Signal failures at the Bahanaga Bazar Railway Station need to be analysed for the past one year to determine a trend of staff bypassing the signalling algorithms. This may well be one of the causes of the accident.

All the wiring of signalling, points and crossing settings and all other sensitive equipment are housed in the Relay Room. Once points are set for a route and the signal is given, and there is a change, the Relay Room can be opened for any adjustment of signalling equipment or the signalling gear. But the Relay Room has a double-lock system—one key is with the operations department or station master and the other key is with the signalling staff or the electric signal maintainer (ESM). Unless both the keys are inserted, the Relay Room cannot be opened. Was the Relay Room opened that fateful day, and were changes made?

There must be repeated counselling of signal maintenance staff and a detailed inspection of all railways systems.

Moreover, all activities, whether done by the station master or by the ESM, are logged in a data-logger—it is equivalent to an airplane’s Black Box; it records all the acti­vities before an event. One report claims that the data-logger says that the driver of Coromandel Express was signalled to take the loop line, and hence the accident. But railway officials disagree. They say the accident took place due to “deliberate inter­ference with the electronic interlocking system”. “You get green signal only after fulfilling all the pre-conditions such as whether the route is set and everything is right. Even if there is a minor problem, technically, there cannot be a green signal in any circumstance; it becomes red. It can’t go green unless and until someone has tampered with it,” says an official.


Some railway officials say the accident is entirely due to privatisation of track and signal departments. “Earlier, we could attend to even a minor failure in quick time, but now we have to wait endlessly for private company technicians who installed the systems,” says an official. He adds that there has to be rethinking as to which sectors of the Indian Railways must be privatised—such as catering and supplying blankets—and which core areas must be managed by the Railways themselves.

There are also reports that maintenance work was being done on the electrically-operated boom barrier gate earlier in the day. In such instances, it is possible for inaccurate readings to appear on the screen indicating that interlocking must not be allowed. Often when railway staff members encounter this problem, they resort to “overrides”, disregarding the dangerous consequences it can have.

There have been many instances where railway rules have been flouted. Since these mistakes did not lead to an accident, they were forgotten. But top railway officials have often reported such errors to their superiors. According to a confidential note prepared by the South Western Railway headquarters, a serious accident was averted on February 8 this year at the Hosadurga Road station when the Sampark Kranti Express almost collided with a goods train in the loop line. “Due to the alertness of the Loco pilot, the train was stopped before entering the wrong line, and averted a major disaster,” the note says. It says that there are serious flaws in the railways system, and current methods “contravene the essence and basic principles of Interlocking. How can anybody meddle with the Interlocking gears without opening the Relay Room?”


Several reports and notes have reiterated the fact that there must be repeated and persistent counselling of signal maintenance staff and a detailed inspection of all railways systems, including the signal manual. It is time some serious work is done on this front to ensure that the precious lives of the passengers, as well as the railway staff, are not put at risk. In any case, there is little doubt that only an unbiased and comprehensive inquiry can unearth the complete sequence of events, including the vital point: what went wrong?

(The author is a former Indian Railways official who wishes to remain anonymous)

(This appeared in the print as 'Out of The Loop')

Important: We are happy to announce that we have successfully completed the migration of our site to enhance your experience as valuable user. But due to the scale of operations some data discrepancies may arise. We apologize for any inconvenience and thank you for your patience and understanding during this period.