London Gatwick Airport Amadeus Computer Shut Down Crowds
Credit: CARL DE SOUZA/AFP/Getty Images

A network outage caused delays and confusion at airport check-in counters around the world on Thursday. The issue was resolved within a few hours, although some airports are still operating with delays.

Passengers at airports from Baltimore to Singapore reported long lines (some up to two hours) because of an internal issue with software from IT firm Amadeus.

The firm’s Altea software is used by more than 100 airlines worldwide. The airlines affected by the outage included Air France, Southwest, Lufthansa, British Airways, Qantas, China Air and Korean Air.

“Amadeus can confirm that our systems are recovered and are now functioning normally,” a spokesperson for the company told Travel + Leisure. “During the morning, we experienced a network issue that caused disruption to some of our systems. As a result of the incident, customers experienced disruption to certain services.”

Amadeus technicians gradually restored service to airlines that reported outages. Some of the outages only lasted a few minutes.

London’s Heathrow Airport said that their outages were only “intermittent” but British Airways customers were unable to check in online. Passengers checking in at Singapore’s Changi Airport received boarding passes written by hand.

Passengers who are flying on Thursday can contact airline customer service to inquire about system outages at their airport. Those who are checking in at the airport should allow extra time as airports catch up on delays.