US flight cancellations surge after nationwide ground stop due to router failure

The Federal Aviation Administration issued a rare nationwide ground stop for all aircraft in the United States on Friday, November 14, 2026, following a technical infrastructure failure. This disruption resulted in more than 16,000 flight cancellations across Friday, November 14, and Saturday, November 15, 2026. The incident was triggered by communication and radar issues caused by a router failure during routine maintenance work.

Technical maintenance causes disruption

The technical failure occurred while contractor L3Harris was performing maintenance to replace old copper communication lines with fiber optic cables. US Secretary of Transportation Sean Duffy stated that the incident was caused by routine work and a router failure during the cable replacement process. While the disruption caused significant delays, more than 3,500 aircraft already in the air were able to land following standard procedures during the disruption.

The Federal Aviation Administration stated that the incident was not caused by a cyberattack. Additionally, the US Department of Homeland Security stated there was no link to the Microsoft outage that occurred on Thursday, November 13, 2026. FAA Administrator Bryan Bedford stated that the worst is behind the agency and excluded the possibility of a cyberattack.

Impact on flight schedules

The scale of the cancellations was significant for both commercial and private aviation. On Friday, November 14, 2026, approximately 12,000 flights were cancelled, which included 9,000 commercial flights and 3,000 private flights. For Saturday, November 15, 2026, the Federal Aviation Administration estimated that between 4,000 and 5,000 of the 41,000 scheduled flights would be cancelled.

Specific airports reported high levels of disruption. Boston Logan International Airport reported a cancellation rate of over 31%. Montreal-Trudeau International Airport saw approximately 100 cancellations within a 24-hour period, including 61 on Friday and about 40 on Saturday. A spokesperson for Aéroports de Montréal, Anne-Sophie Hamel, provided data regarding the Montreal disruptions.

Infrastructure and modernization context

The disruption occurred as the United States manages existing issues regarding aging infrastructure and labor shortages in aviation. The White House had requested an additional $30.1 billion for modernization the day before the incident occurred. These issues have been exacerbated by the COVID-19 pandemic.

The US Department of Transportation expects a return to normal operations by Sunday evening, November 16, 2026. The incident highlights the ongoing challenges in maintaining critical communication and radar systems within the national airspace.

Glossary

• ground stop — A ground stop or ground delay is an action issued by the FAA. It can be issued due to an equipment outage.
• Boston Logan International Airport — Boston Logan International Airport (BOS) is an airport.
• Montreal-Trudeau International Airport — Montreal-Trudeau International Airport is an airport used by CTP participants. It is used for travel to or from the U.S. via Air Canada, Air Canada Express, and Air Canada Rouge flights.
• Aéroports de Montréal — Aéroports de Montréal provides security at Montréal–Pierre Elliott Trudeau International Airport.