FAA lifts nationwide US ground stop after telecommunications outage

The US Federal Aviation Administration (FAA), the agency that regulates civil aviation in the country, lifted a nationwide ground stop on Friday evening. It had been imposed citing "extraordinary circumstances and reasons for safety". The order affected thousands of flights and was the third nationwide halt of all departures since the September 11, 2001, attacks.

The FAA issued the stop at 3:54pm Eastern Time (20:54 GMT) on Friday because of a telecommunications outage affecting air route traffic control centres, which manage flights crossing the country. US Transportation Secretary Sean Duffy said the airspace reopened at 8:15pm ET, after more than four hours. He warned that flights would resume slowly and depend on the availability of pilots and flight attendants.

Cause

Duffy said the outage came from switches and routers that were overloaded with data and went down. He said communications and radar capabilities were not lost entirely. Homeland Security Secretary Markwayne Mullin said no cyberattack was linked to the incident and the public was never in danger. Ron Bartsch, a professor of international aviation law, questioned why a backup system did not take over immediately.

Impact on passengers

Aviation analytics firm Cirium said that after 4pm ET about 11,000 flights carrying more than 1.5 million passengers were still scheduled to depart. By 7:05pm ET at least 827 flights had been diverted: 670 returned to their departure airports and 157 landed elsewhere. According to FlightRadar24, more than 4,700 flights were cancelled and 10,000 delayed on Friday, with another 700 already cancelled for Saturday.

Duffy acknowledged that tens of thousands of travellers were stranded and called for $50bn in upgrades to the air traffic control system. He expects operations to be back up by the Thanksgiving travel period, which begins in less than two weeks. Aviation safety expert Todd Curtis said that even once the technical issues are fully resolved, getting back to normal would take more than a day. Passengers are advised to check flight status with their airlines.