The world’s largest fleet of planes was grounded for hours on Wednesday by a cascading outage at a government system that delayed or canceled thousands of flights across the United States.
The White House initially said there was no evidence of a cyberattack behind the outage, which ruined the travel plans of millions of passengers.
US President Joe Biden said on Wednesday morning that he had commissioned the Department of Transportation to investigate.
Whatever the cause, the outage demonstrated how dependent the world’s largest economy is on air travel, and how dependent air travel is on a computer system called “Notice to Air Missions,” or NOTAM.
Before commencing a flight, pilots must consult NOTAMs listing potential adverse effects on flights, from runway construction to possible icing.
The system used to be phone-based, with pilots calling specific flight service stations for information, but it has gone online.
The NOTAM system collapsed late Tuesday, resulting in more than 1,100 flight cancellations and 7,700 flight delays as of midday Wednesday, according to flight-tracking website FlightAware.
Chaos is expected to grow as a backup connection.
According to aeronautical data company Cirium, more than 21,000 flights were scheduled to depart from the United States on Wednesday, mostly domestic, and about 1,840 international flights are scheduled to head to the United States.
Chicago, Los Angeles, New York and Atlanta airports experienced delays of between 30% and 40% of flights.
“We’re going to see the impact of this, this morning’s delays through the system throughout the day,” Transport Secretary Pete Buttigieg said in an interview on CNN.
“Now we need to understand how this could have happened in the first place. Why the usual redundancies that would keep it from being so disruptive haven’t stopped it from being disruptive this time around.”
According to Federal Aviation Administration (FFA) recommendations, the NOTAM system went down at 8:28 p.m. Eastern (1:28 a.m. GMT) Tuesday, preventing new or changed notices from being distributed to pilots.
The FAA resorted to a phone hotline to maintain overnight departures, but as traffic increased during the day it overwhelmed the phone backup system.
The FAA ordered all departing flights early Wednesday morning, affecting all passenger and ship flights.
Some medical flights were authorized and the cancellation had no impact on military operations or mobility.
Flights for the US military’s Air Mobility Command were not affected.
Mr Biden said Wednesday morning he was briefed by Mr Buttigieg.
“I just spoke to Buttigieg. You don’t know what the cause is. But I was on the phone with him for about 10 minutes,” Mr. Biden said. “I told him to get in touch with me directly if they found out.
Mr Buttigieg said on CNN that the order to ground all departing flights came out of prudence, but that mass disruptions to US air travel are unacceptable.
“We need to design a system that doesn’t have this type of vulnerability,” Mr. Buttigieg said.
European flights to the US appeared largely unaffected. Airlines from Ireland’s Aer Lingus to Germany’s Lufthansa said there was no impact on their flight schedules.
It was the latest headache for travelers across the United States, who faced flight cancellations over the holidays amid winter storms and a staff technology outage at Southwest Airlines.
They also encountered long queues, lost luggage, and cancellations and delays over the summer, as travel demand slumped from the Covid-19 pandemic and staff cuts at airports and airlines in the US and Europe took place.
https://www.belfasttelegraph.co.uk/news/world-news/flight-disruptions-cascade-across-us-after-computer-outage-42279737.html Flight disruptions cascade over US after computer failure