Canberra Airport was getting back to normal after a day of delays following a computer glitch caused chaos for the air-traffic system.
By the evening, planes were departing and arriving pretty well on schedule.
The cause of the earlier disruption was a computer failure which meant that immigration information couldn't be processed by the Australian Border Force. The long queues meant that international flights clogged up the airport in Sydney and then affected domestic flights, including those to and from Canberra.
Towards the end of the morning, the Sydney problem was resolved but it wasn't clear how long the back-log of displaced aircraft would take to clear fully.
The ABF did not explain exactly what had happened. Two months ago, there was similar tech failure when SmartGate passport control machines wouldn't operate.
On the latest outage, the ABF said mid morning: "All issues have now been rectified. We appreciate the patience of passengers at this time and apologise for any inconvenience this may have caused."
But would-be travellers in Sydney had vented their anger on social media, describing the queues as "terrible" and "absolutely crazy". There was no great display of anger at Canberra airport.
The situation wasn't helped by strong winds in Sydney. Jetstar said, "Strong winds are affecting some domestic flights in and out of Sydney Airport today. As a result, several domestic services have been cancelled...We appreciate delays are frustrating, however safety is our highest priority," the airline said in an online statement."