In contrast, ST did not observe any queues at Terminals 1, 2, and 4.
Mr Steven Chen, 49, who works in the IT industry, was with a group of friends at the airport on Friday morning to see one friend off.
He said they had just finished their meal at an eatery in Terminal 3 at around 11am when they heard the announcement over the PA system about the system issues.
Their friend, who was flying with a two-year-old child, took about an hour to get into the departure area even though they were given priority.
“They started queueing at about 11.45am, and reached the front of the queue only at about 12.30pm,” he said.
“It took them another 10 to 15 minutes to clear the automated gates.”
Meanwhile, Ms Margaret Page, 58, said she had a much smoother experience while in the queue.
It had taken all of about 15 minutes for the Canadian to pass through the departure gate after she first started queueing.
“This is my second time in Singapore but, the last time I was here, things weren’t like this.
“Technical issues do happen now and again, and I think it was quite thoughtful of the airport staff to give those of us in the queue a bottle of water,” she added.
Additional reporting by Jefferson Lin Zi Xuan, Judd Siow Rui Bin and Josiah Teo