Changi Airport Group (CAG) yesterday admitted that there was a delay in communicating new flight details to passengers, and said this was because time was needed to decide whether to keep those affected at Terminal 2 or move them to Terminal 3. This led to confusion for travellers who arrived at the airport after the closure and were unsure of where to go, and for those who were already at T2 and held at the tarmac for as long as four hours.
They were provided water, and those who needed special assistance, for example, pregnant women and the elderly, were moved to rest areas.
The fire, which was detected at about 5.40pm on Tuesday, was put out quickly. But passengers had to be evacuated and flights diverted to T3. T2 resumed normal operations at 3am yesterday.
Responding to queries from The Straits Times, CAG spokesman Ivan Tan said last night that a key challenge was having to plan "under conditions that were evolving and uncertain". "A wrong decision would have resulted in chaos in the terminals," he stressed.
The original plan was to hold passengers at T2 until it was given the all-clear. "This would have been the least disruptive option for the passengers to return to T2, either to board their flight or to collect their luggage," he said.
But the situation was fluid, and when it was assessed that an all- clear for T2 would take longer than expected, the decision was made to transfer flights from T2 to T3.
Passengers were then moved to T3 utilising all available resources, including vehicles owned by contractors working on the Changi East, or the future Terminal 5, project.
The T2 to T3 transfer, however, meant that significantly more airport staff had to be reallocated to T3, many of whom were themselves earlier evacuated and had to be reorganised, Mr Tan said.
"With more flights now operating at T3, our teams had to optimally allocate resources such as check-in counters, aircraft parking bays, gate holdrooms and baggage collection belts," he added.
Normal operations at T2 resumed about nine hours after the evacuation, which was ordered by the chief of the Airport Emergency Service at about 6.10pm as smoke had seeped into the terminal.
This was about half an hour after the fire started in a room with air- conditioning equipment.
The key priority at the time was to protect the health and safety of the terminal's occupants, CAG said.
Eventually, thousands of airport workers, with the help of airport partners, stayed beyond their shifts to help clear the backlog.
In total, the airport handled 308 flights, with almost 55,000 passengers, from 6pm on Tuesday to 3am the following morning.
"Foremost in our efforts was ensuring the safety of all, while minimising the inconvenience to passengers. We knew that as a result of the flight disruptions, many people's travel arrangements were affected and a good number were anxious about the situation," he said.
The first flight to leave T2 once operations resumed was IndiGo Flight 6E54, which departed Singapore for Chennai at 5.40am.
Other than a faint smoky smell lingering in the air, there were few signs that hours before, a fire had caused the whole terminal to be evacuated and closed.
Mr Avneesh Mehta, 21, was among passengers who checked in for that first flight at about 4am.
The Indian national, who had been in Singapore for a five-day holiday, said: "I am glad that everything is now in order. I didn't even know there was a fire that caused such a huge impact."
It was also business as usual for many of the shops and eateries at T2, except for two which suffered water damage from the sprinklers.
•Additional reporting by Ng Huiwen