A major communication failure in the United States’ air traffic control network disrupted aviation operations nationwide on Friday, November 13, after the Federal Aviation Administration (FAA) ordered a temporary halt to departing flights across the country. The shutdown affected major airports, stranded thousands of passengers and triggered widespread cancellations and delays, raising concerns about the reliability of America’s ageing aviation infrastructure.
The FAA issued the nationwide ground stop following intermittent telecommunications problems at several regional air traffic control centres. The agency said the decision was taken as a precaution to ensure passenger safety after communication and radar systems experienced instability.
The restrictions lasted approximately five hours before the FAA allowed departures to resume at around 8.15 pm Eastern Time. However, the lifting of the order did not immediately restore normal flight operations. Airlines warned that disruptions could continue through the weekend as they worked to reorganise aircraft, crew schedules and passenger bookings.
What caused the nationwide flight disruption?
The communication failure began at approximately 3.36 pm Eastern Time, affecting radar information and communications between air traffic controllers and aircraft. According to Transportation Secretary Sean Duffy, the problem was linked to an ageing telecommunications network whose switches and routers became overloaded with data.
The older equipment reportedly struggled to process information consistently, resulting in intermittent disruptions across air traffic control facilities and terminal radar approach control centres.
Duffy explained that the FAA had not completely lost its radar or communication capabilities. However, inconsistencies in the information being transmitted created potential safety concerns. Authorities therefore decided to suspend departures rather than risk allowing aircraft to operate under unstable conditions.
At the time of the incident, more than 3,500 aircraft were reportedly in the air. Air traffic controllers followed established safety procedures to manage their movements and guide them towards safe landings. Duffy said the number of aircraft remaining in the airspace had fallen to fewer than 400 as flights gradually landed.
The FAA said technicians investigated the telecommunications failure and tested the systems before allowing normal departures to resume.
Thousands of flights affected across US airports
The nationwide ground stop caused significant disruption at some of America’s busiest airports, including Chicago O’Hare, Dallas-Fort Worth, Denver International, Los Angeles International and Ronald Reagan Washington National Airport.
According to aviation analytics firm Cirium, around 11,000 flights carrying more than 1.5 million passengers were scheduled to depart from US airports after 4 pm Eastern Time on Friday.
Flight-tracking platforms reported thousands of cancellations and delays as the situation developed. At least 600 flights were diverted during the disruption, while many others remained grounded or were forced to return to their departure airports.
American Airlines, Delta Air Lines and United Airlines were among the carriers dealing with major operational challenges. Some passengers were left waiting inside aircraft for several hours, while others faced long queues at airport terminals as they tried to rebook their journeys.
The disruption also affected international aviation. Several international services faced restrictions, while airlines operating between the United States and Canada cancelled or adjusted their schedules. European aviation authorities also introduced temporary measures affecting certain US-bound departures.
Cargo operations experienced delays as well, creating concerns about the movement of commercial shipments and time-sensitive goods.
Although departures resumed on Friday evening, the backlog created by the shutdown continued to affect Saturday’s flight schedules. Airlines had to reposition aircraft and ensure that flight crews were available within their permitted duty hours before restoring services.
Was the communication failure a cyberattack?
The incident raised questions about whether a cyberattack or deliberate interference had affected America’s aviation network. However, Homeland Security Secretary Markwayne Mullin said preliminary assessments had found no evidence of a deliberate attack or national security threat.
Officials said the disruption appeared to be related to technical problems within the telecommunications infrastructure. Investigations were continuing to establish the precise circumstances behind the failure.
There were also questions about whether the FAA’s recently introduced artificial intelligence-supported air traffic management system, known as SMART, had contributed to the outage. However, the company behind the technology said the disruption was not caused by its system.
Officials also indicated that the incident was unrelated to a separate Microsoft service disruption.
Ageing aviation systems under scrutiny
The nationwide shutdown has renewed concerns about America’s outdated air traffic control infrastructure. Several parts of the network continue to depend on older technology, including analogue telecommunications equipment, switches, routers and copper communication lines.
Duffy argued that replacing individual components would not be enough and called for a comprehensive modernisation of the country’s air traffic control network.
Congress has already approved $12.5 billion towards the modernisation programme. However, the administration is seeking additional funding of approximately $30 billion to complete the broader upgrade. Mullin said a comprehensive overhaul could cost around $50 billion.
The latest incident has also brought back memories of January 2023, when an FAA computer system failure involving the distribution of flight safety notices disrupted thousands of flights across the country.
