Australian travellers are among many being affected by what is reported to be a global outage of the Sabre check-in and booking system used by a number of airlines worldwide.
It is understood that a connectivity issue is suspected as being the cause of the failure.
Virgin Australia, which went live with its newly implemented Sabre system in January, is currently enacting manual workarounds to get its customers onto their planes, a spokeswoman said. The failure is thought to have taken effect at 1:40pm and caused significant delays.
Virgin confirmed the problems were at the vendor’s end and were not related to the Optus router issue that caused a two-hour outage to the same system nearly two weeks ago.
Virgin US is also affected.
Virgin customer Paul Abbe, at Perth Airport, posted a photo to Twitter of the handwritten boarding pass he had been given by the airline's staff.
He told iTnews he had checked in online and was already on the way to his boarding gate when he was called back to complete the manual process.
He said it was "a bit chaotic" and staff were clearly taken by surprise.
"Handwriting the boarding pass was a long drawn-out process. It took about 20 minutes for me to get back through check-in and I was pretty much at the front of the line," he said.
Qantas and Jetstar are both unaffected. Qantas uses the Amadeus system and Jetstar is using Navitaire.
Update 4:30pm: A spokeswoman for Sabre advised iTnews the problem had been resolved.
"Sabre systems are coming back online, and we are closely monitoring. We apologise for the inconvenience," she said.