Ants chewed up the cables inside an Electro Pneumatic brake. Officials say ants are difficult to manage, but regular pest control is carried out.
The lifeline of Mumbai, the suburban local trains carry lakhs of people every day, but in this case, a rake was also ferrying thousands of hidden passengers - red ants. To make matters worse, these red ants gnawed through the primary brake cables.
The incident happened inside a Kalyan-Chhatrapati Shivaji Terminus local train around 1.30 pm yesterday and the coaches were comparatively less crowded.
"As it crossed Matunga, the motorman saw a flicker on the dashboard, indicating that one of the cables connecting the EP brake was not working efficiently," said a Central Railway (CR) official on condition of anonymity.
The Electro Pneumatic (EP) brake being the primary one inside the Siemens rake, the motorman then had to shift his attention to the secondary brakes.
Motormen have come to rely on the EP brake, in which the electrics take care of the braking and acceleration with little manual or mechanical intervention. This brake is like a joystick on the right side of the dashboard panel and the entire train, including its speed and braking, can be controlled by using it.
Backup provisionSources said that after the EP brake failure, the rake was then run as a normal one, without the EP brake, all the way to CST, without it getting hampered by any technical glitch.
During this time the secondary brakes - which comprises an Auto brake - was put into use to take the train all the way till CST. "The train was then taken to Kurla carshed for inspection," added the official. This is when the officials found thousands of red ants chewing the already damaged cables and insulators of the EP brake.
The official added, "The SKS12 cable insulator and in-coder cable were found damaged. We then had to replace them with a new one out of the stock."
Meanwhile, the CR officials blame the motormen for not knowing to operate Auto brakes which are as good as the EP ones. Sources said that ever since the new rakes have come in, a single joystick is sufficient for acceleration and deceleration of trains. The Auto brakes and other semi-manual ones are on the left side of the dashboard panel.
"The motormen have more or less forgotten to use the Auto brakes, which was earlier an important part in older trains while manoeuvring them. We will now be training the 800-odd motormen to apply Auto brakes on a regular journey," said the CR officials. The training will begin on the Kalyan-Karjat/Kasara route in the next couple of days during off-peak time when the motormen will be monitored while applying Auto brakes
In this case, CR officials claim that the motorman could have easily used the secondary brakes without panicking. These Auto brakes are semi-manual ones where there is little electronic control. When the Auto brakes are pressed, pressure is applied or released through a piston that then controls the braking of the entire rake. This was how the older rakes used to function.
Officialspeak"There is no need to panic as the braking system is foolproof. There are three other brakes to ensure that there are no problems in the running of the train. Ants are difficult to control but regular pest control is carried out," said Narendra Patil, chief PRO, CR.
Combating the ant menaceEvery rake undergoes pest control during the periodic overhauling every 18 months. Apart from this, the authorities try to ensure that there are no anthills inside the carshed, where trains are parked in large numbers.
Dealing with emergenciesThere is a 'dead man handle' - that is like a spring on the joystick - which ensures that the train comes to a halt if the motorman is incapacitated or other brakes don't function. The guard too has an emergency brake inside his cabin that is completely manual.
The joystick where the EP brake is present also has a regenerative brake in it wherein the train saves power of 33 per cent every time the brake is applied. When the EP is pulled backward, the regenerative braking works up to the speed of 5 km/h