Dhaka, Nov. 14 -- A communications failure that halted flight departures across the United States on Friday has renewed scrutiny of the country's aging air traffic control network, raising questions about its resilience even as the government spends billions of dollars to modernise it.

The Federal Aviation Administration ordered a nationwide ground stop, preventing aircraft from departing US airports, following "a communication issue impacting all Air Route Traffic Control Centers," Transportation Secretary Sean Duffy said in a post on X.

Duffy later attributed the outage to a problem with the FAA's legacy network, saying switches and routers had become overloaded with data and went down. It was not immediately clear what caused the equ...