Saturday, November 24, 2012



Rules ignored causing worst ever accident

The Kandy-Colombo Intercity Train follows Newton’s Law of Gravity

 

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by D.C.Lelwela.

The Intercity Train service from Colombo to the provincial capitals of Kandy, and Anuradhapura were introduced by Sri Lanka Railways in the early 1980s as the new government thought it a long felt need to provide an improved service to the general public. It primarily served the business community and any other travelers of these main cities who could afford the highly priced ticket and wished to travel to the metropolitan city and back speedily in comfort and spending less time on the journey ( by virtue of the lesser number of stops on the way.)

The Kandy intercity, for example stopped only at the intermediate stations of Veyangoda and Peradeniya Junction. Piped music was provided in the train throughout the journey for passenger entertainment. Refreshments could be ordered to one’s seat. The train also occasionally carried families with children who were ‘served by nature’ with a panoramic view, from Rambukkana to Kadugannawa, of lush green hills on both sides of the railway track planted with tea, well kept by teams of women, who would be seen garbed in their special aprons, plucking the tender two leaves and bud of each shrub every morning, rain or sun. There were also the yonder mountain ranges cascading against the deep blue skyline providing a backdrop to the scenery. A train full of people therefore is, very often, certainty.

The two up and down intercity Express trains between Colombo and Kandy were timed to run on a schedule convenient to the people. Only experienced and competent crew members would be selectively ‘booked’ to work the train in order to ensure its reputation. The department was quite keen that no officer on board would make any error that would negate departmental efforts in achieving best results. They had to make sure that they gave of their best under all circumstances. But on this day the inThe railway track from Colombo to Kandy which is a part of the Main Line of the railway system consists of the section up to Rambukkana that permits a maximum speed of 55 mph on straight track in flat country. From Rambukkana to Kadigamuwa is the most treacherous section in the entire railway system- where the gradient is very steep – in fact the steepest (1 in 44) and the curvatures are continuous reverse curves of five and 10 chains all the way. Such track geometry between Rambukkana and Kadugannnawa cannot permit a maximum speed of more than 20 mph.

In the design stage of locomotives and rolling stock for special use on the upcountry beyond Rambukkana, the important features mentioned above have to be carefully gone into by the design engineers. And the manufacturer has to comply strictly with such specifications; and the driver, when ascending the slopes such as those mentioned must use extra power and special features have to be availed of as needed. The horse power of the locomotive had to be adequate. Slipping of the driving wheels of the locomotives should be reduced by using sand in the sand boxes provided above the rail wheel contact.

On the day of the journey, the crew have to report to the locomotive shed and go through a check list of the condition and the needs of the locomotive and rolling stock, bring any shortcomings to the notice of the Locomotive Foremen and not leave on the journey until and unless they are completely satisfied that defects if any are attended to. They should also familiarize themselves with the details of the track layout by having thorough ‘road learning’ over the area he will traverse and be aware of any information about temporary speed restrictions before they take charge and leave on the journey.

On January 13 2002, the intercity train started on schedule from Kandy with the hope of reaching Colombo safely and on time. It had left Kandy railway station at 6.30 am as scheduled. Everything on the check list was cleared by the crew and all seemed to be in order before they left Kandy. The train arrived at Peradeniya railway station at 6.42 am, and left after a minute’s stop on the next lap of its journey to run express all the way up to Kadugannawa which they passed non stop at 6.57 am and began the descent down to Balana reaching the down outer home signal of the Balana railway station at 7.05 am. with the train still in good control of the driver. This was however a non-scheduled stop.

It resumed its journey from the temporary stop at the down outer home signal at Balana, and passed the Balana railway station at 7.08 am. Having entered the section between Balana and Ihala Kotte, it was passing the village of Makehelwewa, when the driver noticed that the speed of the train was unusually high and the vacuum reading had dropped to zero. He began to worry that the permissible speed may have been exceeded already. However he was unable to determine the exact speed of the train since a speedometer was not available.

He has immediately instructed his assistant to apply the hand brake. The locomotive hand brake was applied by the driver’s assistant. The guard and the under guard have also duly applied their handbrakes in the two brake vans, with the hope of bringing the train speed under control. The panic stricken driver then had applied the hydro dynamic brakes as well. That too seemed ineffective. All attempts made to slow the train were of no avail. The train, by then, was running out of control and was galloping down the slopes. There was only one thing left for them to do. That was to pray.

This was the moment when the Kandy intercity train seemed to ‘defy’ the best efforts of the driver and his assistant at maintaining its speed within limits considered safe. Instead, the train seemed to have ‘opted’ to follow the Newtonian Laws of Gravitation, and rushed down the rail track along a very steep 1 in 44 gradient with increased acceleration. The only resistance acting against the speeding train was the wind, frictional resistance created by the application of the hand brakes, friction at the rail wheel contact and any resistance at the wheel bearings (negligible).

The train continued to ‘run away’ in this erratic manner until it passed the Kadigamuwa railway station at 7.22 am. The speed of the train then was so high that the train crew while passing Kadigamuwa railway station could only throw the tablet (with pouch) they had with them for the preceding section on to the platform and with the greatest of difficulty pick up the tablet for the section ahead from the station staff standing on the platform ready but with utmost care to see that he was standing at a safe distance from the speeding train.

The driver, fearing that a major calamity was awaiting in that tablet pouch bringing a message about an obstruction in forward section, could only breathe a sigh of relief when he got the tablet to proceed into the section with the best hopes so that the possibility of an obstruction ahead was totally eliminated.

Passing Kadigamuwa, whilst the momentum gathered so far up was pushing the train significantly, the situation did not seem to change. When it reached a point on the track where the track geometry could no longer sustain such a speed well beyond the permitted limit and hold its dynamic stability together. Thus, when negotiating a very sharp reverse curve of ten chain radius at 53 m 05 ch, near the village of Kirivallapitiya the train derailed at a speed far in excess of the permitted speed for the section. The point of derailment was 2 miles 37 chains away from the Kadigamuwa railway station

According to the details that emerged about the journey on this day from the moment the train crew took over the empty train set at Kandy up to the time of the derailment, the primary cause of the derailment was found to be over speeding at the point of derailment while there was evidence that the train was over speeding all the way from Balana railway station. Other contributory factors were the defects in the brake system in the locomotive and the passenger cars, the consequent inadequacy of the brake power on the train, and the lack of a speedometer in the cab of the locomotive for the guidance of the driver and the consequent inability of the driver to apply the brakes and use the available brake power in time so as to keep the speed under control.

The train formation consisted of a M6 Type Diesel Electric Locomotive, made by Henschell of West Germany suitable for use in the up country and imported in the nineteen eighties and six passenger cars along with two brake vans. All vehicles have been designed for special use with the rigid wheel base as specified and other requirements satisfied. However, four of the passenger cars used on the train had been `overdue’ for ‘heavy’ repairs. Of these, one car had been overdue for more than three years. The train set had not been ‘vacuum tested’ in the Kandy locomotive shed before the empty set left on the journey that morning. The brake system too has not been tested.

Among the wreckage were several twisted bogies and cars totally damaged beyond use. Brake blocks on several cars have been observed, soon after the accident, to be shattered and the surface of some others blackened showing that the brakes applied had not been sufficiently effective.

The derailment of this runaway train was one of the most serious accidents seen in the Sri Lanka railways since Independence. 15 passengers were killed while over 200 were injured, most of them very seriously. The accident was reported over a public telephone to the Rambukkana railway station by an outsider who saw it.

For the upkeep of the regular train services every day, it goes without saying that the various sub departments of the railway have to play their part in ensuring that they feed the necessary inputs such as carriages and locomotives that are repaired and in good order to the operating department to enable them to run the daily service efficiently and without the risk of accidents. That was possible only if these vehicles have gone through the repair schedules on due dates. If not either trains have to be cancelled for want of passenger cars or risks have to be taken in using such vehicles.

(The writer is a former General Manager of Railways)

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