Major European airports are starting to recover after they were hit by a cyberattack that affected check-in systems, causing flight cancellations and huge delays for thousands of passengers over the past two days.
Starting late Friday, major airports in Brussels, London and Berlin were hit by disruptions to electronic systems that snarled up check-in and sent airline staffers trying options like handwriting boarding passes or using backup laptops. Many other European airports were unaffected.
It was not immediately clear who might be behind the cyberattack, but experts said it could turn out to be hackers, criminal organizations, or state actors.
The cyberattack affected the software of Collins Aerospace, whose systems help passengers check in, print boarding passes and bag tags, and dispatch their luggage. The U.S.-based company on Saturday cited a “cyber-related disruption” to its software at “select” airports in Europe.
While departure boards for London’s Heathrow and Berlin’s Brandenburg airports were showing signs of smoother arrivals and departures on Sunday, Brussels Airport was still facing considerable issues.
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Ihsane Chioua Lekhli, a spokesperson for Brussels Airport, said 45 outbound and 30 inbound flights were cancelled on Sunday, more than double the number a day earlier: 25 departures and 13 arrivals cancelled.
The cyberattack affected only computer systems at check-in desks, not self-service kiosks, she said, and teams were turning to alternative backup systems and pulling out laptop computers to help cope with the impact.
It remained unclear when the situation would be fixed, she said: “For now, we have no idea on the timing, we’re taking it day by day.”
The airports advised passengers to check the status of their flights before traveling to the airports and to use alternative check-in methods.
“Work continues to resolve and recover from Friday’s outage of a Collins Aerospace airline system that impacted check-in,” a Heathrow statement said. “We apologize to those who have faced delays, but by working together with airlines, the vast majority of flights have continued to operate.”
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A rolling message on Sunday on the Brandenburg Airport’s web page said: “Due to a systems outage at a service provider, there are longer waiting times. Please use online check-in, self-service check-in and the fast bag drop service.”
Collins, an aviation and defense technology company that is a subsidiary of RTX Corp., formerly Raytheon Technologies, said Saturday it was working to resolve the issue.
“The impact is limited to electronic customer check-in and baggage drop and can be mitigated with manual check-in operations,” it said in a statement.
Cyberattacks and tech outages have disrupted airports around the world in recent years, as air travel increasingly relies on online, interconnected systems.
The aviation sector saw a 600% increase in cyberattacks from 2024 to 2025, according to a report by French aerospace company Thales released in June, AFP reported.
contributed to this report.