A nationwide ground stop that halted flights across the United States for about five hours on Friday began during routine work to replace old copper telephone wire with fibre-optic cable, Transport Secretary Sean Duffy said on Saturday.
Contractor L3Harris was switching lines at a remote Federal Aviation Administration site when a router began flooding other air traffic control systems with data, Duffy said. The fault disrupted communications and radar feeds at as many as 17 of the 22 air traffic control centres, according to FAA Administrator Bryan Bedford.
The FAA ordered all departing flights to stay on the ground from about 3:54pm Eastern time, citing extraordinary circumstances. The stop lasted about five hours and was lifted at around 8:15pm. Nearly 10,000 flights were cancelled and more than 7,000 delayed, USA Today reported.
Duffy said investigators still had to determine whether the fault came from a contractor error or a faulty router. L3Harris said it was working with the FAA on the investigation and had completed more than 70% of the planned switch from copper to fibre.
Officials stressed there was no evidence of a cyberattack. Duffy also used the disruption to press Congress for more money to modernise air traffic control, raising his request to $50 billion after Congress approved $12.5 billion last year. Bedford said flights should return to normal by Sunday.
Source: USA Today
