An overburdened Metro train buckled on Wednesday morning as its air-conditioning gave way and sent Calcutta’s trusted transit system into a tailspin.
Trouble began with a malfunctioning microchip in the AC system of a Dum Dum-bound while it was pulling out of New Garia station around 11.45am. The ACs slowed down within minutes, creating a stifling atmosphere in the overcrowded train, and stopped completely at Jatin Das Park station where authorities evacuated the passengers and sent the rake for repairs at Noapara shed at 12.22pm.
Metro authorities said overcrowded AC rakes, pushed to the extreme in the scorching heat, added to the problem.
When the train was inspected at Tollygunge and again at Kalighat — for 10 minutes at each stop — more and more people jostled in.
“Passengers complained of suffocation and so we decided to evacuate them. There was a snag in the microchip that controls the AC,” a Metro official said.
The disruption dislodged the domino and it took almost 40 minutes to restore normality.
A Metro official said he saw the snag coming since all the 13 AC rakes were currently in operation because of the heat and none were getting enough time for the mandatory regular checks.
A Metro rake’s brakes, hydraulics for the doors, electric circuits and the computer system should undergo maintenance checks every day. Besides, ventilation and AC need proper inspection before a train passes through a wash that cleans the exterior with soft brushes and water.
According to officials, each AC rake were making seven to eight journeys each day against four to five journeys till last month. As a norm, at least two AC rakes were kept in the maintenance yard for emergency but now the entire fleet of 13 is in service.
“Commuters skip the old rakes, adding to the burden on AC trains. These trains are making additional journeys and, hence, getting less time for maintenance,” an official said.
The Metro runs one AC train after every non-AC one, the official added.
The arrangements have been made for commuter comfort but it has started taking a toll on the trains.
During non-peak hours — afternoon, early morning and late evenings — an AC train leaves a terminal station after two or sometimes three non-AC rakes. An official said 14 of the 17 non-AC trains were in operation.