Heathrow braces for second day of disruption after cyber-attack on check-in system

Heathrow airport braced for a second day of disruption on Sunday after a cyber-attack knocked out a check-in and baggage system used by multiple airlines, forcing some operations to run on manual processes. The outage affected Muse software from Collins Aerospace, which allows different airlines to share check-in desks and boarding gates at an airport, complicating operations across several hubs.

Airlines and passengers faced continued delays and long queues as the system remained offline at many points of service. British Airways was reported to be operating largely normally at Heathrow using a back-up system, but most other carriers serving the airport were affected. Heathrow said the vast majority of flights had continued to operate and urged travelers to check flight status and arrive in good time. Flight-tracking data indicated about 47% of Heathrow’s departing flights were delayed on Saturday, with some passengers queuing for hours to check in.

Brussels Airport said it had no indication of when the system would be functional again and had asked airlines to cancel about half of departing flights while it works through the disruption. It indicated that manual check-in would continue on Sunday and that extra staff had been drafted to help minimise delays. In Sunday updates, Brussels reported 44 departing flights canceled so far. Dublin Airport, by contrast, said it expected to operate a full schedule on Sunday despite ongoing technical issues and advised passengers to contact their airline for updates. Berlin Brandenburg Airport asked travelers to use online or self-service check-in for the duration of the outage, noting eight cancellations in and out of the airport on Saturday.

Across Europe, Eurocontrol, the bloc’s aviation safety body, said airlines had been asked to cancel half of their flight schedules to and from the affected airports until 02:00 on Monday as operators adjust to the disruption. The European Commission said it was closely monitoring the cyber-attack but stressed there were no indications that the disruption was widespread or severe. In the United Kingdom, Transport Secretary Heidi Alexander said she was aware of the incident and was receiving regular updates as authorities assess the impact.

The incident comes amid broader concerns about the vulnerability of aviation’s increasingly digital infrastructure. Analysts noted that while incidents like these are not new, they underscore how a single software fault can ripple through multiple hubs and carriers that share common IT platforms. It followed a high-profile IT crash last July linked to a software update from CrowdStrike that grounded flights across the United States and prompted renewed attention to resilience and contingency planning within the aviation sector.

Travelers are urged to stay in contact with their airlines and monitor official updates from airports and regulators as the situation develops. Officials emphasized that, while some disruption is expected to continue, there was no evidence publicly at this time of a systemic, industry-wide failure.