U.S. computer outage leads to hundreds of flight delays, cancellations

The Federal Aviation Administration has lifted a ground stop on flights across the U.S. following a computer outage that resulted in thousands of delays and hundreds of cancellations quickly cascading through the system at airports nationwide.

Several flights to U.S. destinations on the departure boards of Canadian airports showed delays of from 30 minutes to over an hour as a result, with a smattering of cancellations. Canada's major airports advised travellers with U.S. routes to check with their airlines about flight status before heading to the airport.

The outage showed the world how dependent its largest economy is on air travel, and how dependent air travel is on an antiquated FAA computer system called the Notice to Air Missions (NOTAM) system.

"Periodically there have been local issues here or there, but this is pretty significant historically," said Tim Campbell, a former senior vice-president of air operations at American Airlines and now a consultant in Minneapolis.

Campbell said there has long been concern about the FAA's technology, and not just the NOTAM system.

"So much of their systems are old mainframe systems that are generally reliable but they are out of date," he said.

The NOTAM system broke down late Tuesday, leading to more than 1,000 flight cancellations and 7,000 delayed flights by midday Wednesday, according to the flight tracking website FlightAware. Airports in Chicago, Los Angeles, New York and Atlanta were seeing between 30 per cent and 40 per cent of flights delayed.

"We are going to see the ripple effects from that, this morning's delays through the system during the day," said Transportation Secretary Pete Buttigieg in an interview on CNN. "Now we have to understand how this could have happened in the first place. Why the usual redundancies that would stop it from being that disruptive did not stop it from being disruptive this time."

Cause not yet clear

White House Press Secretary Karine Jean-Pierre said early Wednesday that U.S. President Joe Biden was briefed on the situation and had directed the Department of Transportation to investigate. There was no immediate evidencethat the outage was caused by a cyberattack, Jean-Pierre said.

Before commencing a flight, pilots are required to consult NOTAM, which lists potential adverse impacts on flights, 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 now moved online.

All aircraft are required to route through the system, including commercial and military flights.

Breakdowns in the NOTAM system appear to be rare.

"I've been flying 53 years. I've never heard the system go down like this," said John Cox, a former pilot and now an aviation safety consultant. "So something unusual happened."

According to FAA advisories, the NOTAM system failed at 8:28 p.m. ET on Tuesday, preventing new or amended notices from being distributed to pilots. The FAA resorted to a telephone hotline in an effort to keep departures flying overnight, but as daytime traffic picked up, it overwhelmed the telephone backup system.

Data from the aviation analytics firm Cirium indicates that more than 21,400 flights were scheduled to depart U.S. airports on Wednesday. The carrying capacity of those flights was nearly 2.9 million passengers, though it's not clear how many tickets were sold.

Democrat Maria Cantwell, chair of U.S. Senate's commerce committee:

It was the latest headache for North American travellers, who faced flight cancellations over the holidays amid winter storms as well as unrelated complications confronting Sunwing Airlines and Southwest Airlines passengers in late December.

Members of the House of Commons transport, infrastructure and communities committee will hold an all-day hearing on Thursday related to those woes. Executives from Sunwing, Air Canada and WestJet are scheduled to appear as are representatives from Transport Canada and executives from some Canadian airports.

WATCH | It could take days to sort out U.S. flight delays:

Thousands of U.S. flights delayed after computer system outage

2 years ago

Duration 2:28

There was more air travel chaos across the United States Wednesday after the FAA air hazard warning system failed, leading to thousands of flights being delayed or cancelled. Officials are warning it could take another day before everything is back to normal.