The city airport’s terminal remained without regular power supply for more than 24 hours since Thursday evening and at least 40 outgoing flights were delayed, 30 of those on Friday morning.

A 33kV power supply line of CESC got snapped during construction work for Metro Rail. Diesel generators were used as back up, but those were tripping frequently, which led to conveyor belts stopping, said officials. Airlines said many baggage could not be sent because of malfunctioning of conveyor belts.

Water supply was affected, too, and large parts of the building were dimly lit. Airport officials said this was the longest period the terminal did not have regular power supply.

The problem had started around 6pm on Thursday, when the 33kV line got damaged, and continued till late on Friday. Airport and CESC officials said it would take till Saturday morning to repair the cable and restore power supply.

The airport, CESC sources said, has two points of supply from the utility, both 33kV. One of them powers the air traffic control, runways and allied infrastructure. The other powers the terminal lights, passenger facilities, escalators, elevators, conveyor belts, etc.

The first point was unaffected. The second point — comprising a main feeder, an alternate feeder, a communication cable — was damaged on Thursday night. “The alert came immediately. A Metro project is underway there…. Work began on a war-footing… and has been on all night, even through the day,” said a source in CESC.

He said the condition of the site was such that a drain had been overflowing and inundating the lines with water, which had been delaying work.

“The cables have been lifted at the site and they have been damaged. There are marks left by an earth-mover. The second point of supply, considering its importance, has to be restored flawlessly as soon as possible,” he said. According to him, the terminal has been running on a series of generators since last night.

“It is a very meticulous and delicate operation, which takes six-seven hours,” he said.

A Metro official said a CESC team had temporarily shifted the underground cables from the area to facilitate Metro work had not removed all the cables. “Prima facie, it seems some cables that had not been shifted were damaged by heavy machinery during Metro work,” the official said.

The Telegraph lists some of the major inconveniences faced by passengers:

Conveyor belts

Airport officials said 10 diesel generator sets were being used to provide power supply to the terminal, of which six were used at a time.

“Till Friday morning, the diesel generator sets were getting stalled several times, causing the conveyor belts to stop. Each time the generator sets were stopping for five minutes on an average and power supply was getting snapped, it was taking 15 minutes for the conveyor belts to start again,” said Kaushik Bhattacharya, the airport director.

This led to slow movement of baggage and flights were delayed. “Also, the inline baggage scanning system was not functioning when the generator sets were getting stalled. Baggage cannot be scanned manually now and so we had to wait for the system to restart, causing delays in departure,” said Bhattacharya.

On Friday morning, 30-odd flights were delayed between 8am and 9.30am for 30 minutes on an average, said officials. However, officials of some airlines said their flights were delayed by more than an hour.

Airport sources said Air-Asia flights to Delhi and Bangalore were delayed by an hour each.

Baggage mishandling

Frequent malfunctioning of the conveyor belts led to mishandling of baggage, said airport and airline sources. Many flights took off leaving behind baggage to avoid further delays. One flight took off without 38 pieces of baggage, said sources.

“Baggage of passengers of several arriving flights had to be manually brought from the aircraft to the carousels on trolleys. Passengers had to wait for even more than an hour to get their baggage,” said an official.

Water, AC and lights

“Passengers at times complained that they were not getting water. This was because the generator sets were malfunctioning and so the pumps were not functioning,” said an official.

The AC system was also not working because the power supply was provided by generator sets. “Only the air circulation system is working,” said airport director Bhattacharya.