The cause that led to the suspension of departures in the US, explained by the US Secretary of Transportation / More than 13,000 flights were canceled in two days

The US temporarily suspended takeoffs nationwide after maintenance work on the air traffic communications system caused problems communicating with aircraft and disruptions to radar flows. The incident occurred during the transition from an old copper cable to fiber optics, and the airspace was reopened the same day after the fault was isolated.

US Transportation Secretary Sean Duffy said that L3Harris was carrying out the work on the telecommunications infrastructure. According to the official, replacing a router caused other control systems to be flooded with more than 1,000 connection attempts every four to five seconds. The situation affected communications between air traffic controllers and pilots, which is why authorities imposed a ground stop for safety reasons.

When the procedure was initiated, approximately 3,500 aircraft were in the air and landed safely. Authorities are investigating whether the incident was caused by human error or equipment failure. The suspension, considered the longest of its kind since the restrictions following the September 11, 2001 attacks, led to the cancellation of thousands of flights. The effects of the disruption could continue for several days because the aircraft and crews are no longer in their planned positions.