Federal authorities halted plane departures within the United States for over two hours on Wednesday due to a problem with a system used by pilots, according to US authorities.
The US Federal Aviation Administration (FAA) said Wednesday at 8:50am ET (12:50 GMT) that the “ground stop” had been lifted and flights were gradually resuming across the country. Departures had been halted after the FAA said it was working to restore a system that alerts pilots to hazards and changes to airport facilities and procedures.
Authorities said the system had stopped processing updated information, known Notices to Air Missions, or NOTAMs, leading to hundreds of flight delays that were expected to persist throughout the day.
“We continue to look into the cause of the initial problem,” the FAA tweeted upon lifting the stop. The agency first tweeted about the issue at 6:29am ET (11:29 GMT).
White House Press Secretary Karine Jean-Pierre said in a tweet that US President Joe Biden had been briefed on the matter and had asked the US Department of Transportation to investigate the cause.
The President has been briefed by the Secretary of Transportation this morning on the FAA system outage. There is no evidence of a cyberattack at this point, but the President directed DOT to conduct a full investigation into the causes. The FAA will provide regular updates.
— Karine Jean-Pierre (@PressSec) January 11, 2023
“There is no direct evidence of a cyberattack at this point,” Jean-Pierre tweeted.
However, Biden later told reporters he had spoken to US Secretary of Transportation Pete Buttigieg and that “they don’t know what the cause is.”
“I told him to report directly to me when they find out. Air traffic can still land safely, just not take off right now,” he said.
In a tweet, Buttigieg said he was in touch with the FAA and monitoring the situation. He later said the affected system had been “fully restored”.
“I have directed an after-action process to determine root causes and recommend next steps,” he tweeted.
FAA has determined that the safety system affected by the overnight outage is fully restored, and the nationwide ground stop will be lifted effective immediately. I have directed an after-action process to determine root causes and recommend next steps.
— Secretary Pete Buttigieg (@SecretaryPete) January 11, 2023
The issue caused arrival and departure delays at airports across the US affecting at least 7,300 flights, according to tracking website FlightAware. Further delays were expected as a knock-on to the morning outage. More than 250 flights had been cancelled by 10:30am ET (15:30 GMT).
In a tweet, the FAA said that all flights in the sky at the time of the issue were safe to land.
“Normal air traffic operations are resuming gradually across the US following an overnight outage to the Notice to Air Missions system that provides safety info to flight crews,” the agency tweeted shortly before 9am ET (14:00 GMT).
The FAA said that the first flights to resume were at the Newark Liberty International Airport in New Jersey and Atlanta Airport in Georgia.
More than 21,000 flights were scheduled to take off in the US Wednesday, mostly domestic trips, and about 1,840 international flights were expected to fly to the US.
Air Force spokeswoman Ann Stefanek said the US military flights were not impacted because the military has its own NOTAMS system separate from the FAA system, and the military’s system was not affected by the outage.
Before commencing a flight, pilots are required to consult NOTAMs, which list potential adverse impacts on flights, ranging from runway construction to the potential for icing. The system used to be telephone-based, with pilots calling dedicated flight service stations for the information, but has since been moved online.
Update 5: Normal air traffic operations are resuming gradually across the U.S. following an overnight outage to the Notice to Air Missions system that provides safety info to flight crews. The ground stop has been lifted.
We continue to look into the cause of the initial problem
— The FAA ✈️ (@FAANews) January 11, 2023
The NOTAMs sent by the FAA are part of a global safety system managed through the United Nations’ aviation agency.
That agency has been leading an effort to overhaul the system to make it easier for airlines and pilots to filter the most important warnings and present them in clearer language, with the lengthy reports at times burying important updates.
For example, in July 2017, an Air Canada flight landed on the wrong runway at San Francisco’s airport and came within seconds of colliding with four other planes.
The notice of the closure of one of the two runways at the airport had been flagged in the pre-flight NOTAM – deep on page eight of a 27-page briefing – and missed by the pilots involved.
The latest incident comes as US travellers have faced several challenges amid a post-COVID lockdown boom in flying over the summer, with long lines, lost baggage, and cancellations and delays common.
At the end of 2022, winter storms and a breakdown with staffing technology at Southwest Airlines also created headaches for travellers in the country.