Planes were stranded on the ground for hours across the United States on Wednesday, leading to thousands of flight cancellations and delays as a government system used to provide safety and other information to pilots collapsed overnight.
The White House initially said there was no evidence the disruption, which disrupted travel plans for millions of passengers, was behind a cyber attack. President Biden said Wednesday morning that he had directed the Department of Transportation to investigate.
The outages show just how dependent the world’s largest economy is on air travel, and how much air travel relies on outdated computer systems to generate alerts known as NOTAMs, or notices to air tasks, to pilots and others.
Before a flight takes off, pilots and airline dispatchers must review the notices, which include information about weather, runway closures or construction, and other information that could affect flights. The system used to be phone-based, with pilots calling a dedicated flight service station for information, but has now moved online.
The NOTAM system glitched late Tuesday and wasn’t fixed until 9 a.m. ET Wednesday, resulting in about 1,200 East Coast flight cancellations and 7,800 by early afternoon, according to flight-tracking site FlightAware. Multiple delays.
The chaos is expected to continue even after the FAA reverses its order to ground the planes. According to aviation data firm Cirium, more than 21,000 flights, mostly domestic, are scheduled to depart from the U.S. on Wednesday, with about 1,840 international flights expected to head to the U.S.
Between 30 and 40 percent of flights were delayed at airports in Chicago, Los Angeles, New York and Atlanta.
“There was a system issue overnight due to the way safety information was transmitted through the system that resulted in the grounding,” Transportation Secretary Pete Buttigieg said at a news conference. “The issue has since been resolved. , which made it possible to lift ground stops at 9am this morning, but we will see ripple effects throughout the system throughout the day.”
Buttigieg said his agency is now turning to understanding what caused the NOTAM system to crash.
Longtime aviation industry insiders don’t recall a technical glitch causing such a severe outage. Some have compared it to the nationwide airspace closure following the September 2001 terrorist attacks.
“Every now and then there will be localized problems, but it’s historically significant,” said Tim Campbell, former senior vice president of airline operations at American Airlines and now a Minneapolis-based consultant.
Campbell said there have long been concerns about the FAA’s technology, not just the NOTAM system.
“A lot of their systems are old mainframe systems, which are generally reliable, but they’re outdated,” he said.
John Cox, a former airline pilot and aviation safety expert, said the aviation industry had talked for years about trying to modernize the NOTAM system, but he didn’t know the age of the servers used by the FAA.
“I’ve been flying for 53 years. I’ve never heard of a system going down like this,” Cox said. “So something unusual happened.”
The NOTAM system malfunctioned at 8:28 p.m. ET Tuesday, preventing new or revised notices from being distributed to pilots, according to the FAA bulletin. The FAA turned to a telephone hotline to guarantee nighttime takeoffs, but as traffic increased during the day, the phone backup system was overwhelmed.
The FAA ordered the grounding of all departing flights early Wednesday morning, affecting all passenger and shipping flights.
Some medical flights can be licensed and the disruption will not affect any military operations or mobility.
Air Mobility Command flights were not affected.
Biden said Wednesday morning that he was briefed by Buttigieg.
“I just spoke to Buttigieg. They don’t know what the cause is. But I was on the phone with him for about 10 minutes,” Biden said. “I told him to report it directly to me when they found out.
Buttigieg acknowledged that the outage caused flight delays and cancellations, but stressed that “the main thing I want everyone to understand is that every step of the way, safety will be our North Star, as always.”
“Our focus now is to understand the cause of the problem,” he said.
Passengers scrambled to reschedule their trips. Many said they struggled to find information on how long the delays lasted.
“There was a lot of frustration, a lot of confusion,” said Ryan Osorsky, who was trying to fly from Washington, D.C., to California for a work meeting. “I came back an hour and a half late (and) still don’t know if I should board because I’ll now miss my connecting flight.”
Julia Macpherson was on a United Airlines flight from Sydney to Los Angeles on Wednesday when she was told there might be delays.
“While I was in the air, I got word from friends who were also traveling overseas that there was a power outage,” said McPherson, who returned to Florida from Hobart, Tasmania. There was still a connection in Denver on the flight to Jacksonville, Florida.
She said there was no announcement on the flight about the FAA issue.
McPherson said her travel had already experienced delays as her flight from Melbourne to San Francisco was canceled and she rebooked from Sydney to Los Angeles.
Similar stories are coming out of Chicago, Washington, Atlanta and other major U.S. airports.
Flights from Europe to the US appear to be largely unaffected. Airlines ranging from Aer Lingus to Lufthansa said their flight schedules were not affected.
It’s the latest headache for travelers in the U.S., who face canceled flights during the holidays amid winter storms and Southwest Airlines staffing technology glitches. They also experienced long lines, lost luggage, cancellations and delays over the summer as travel demand recovered from the COVID-19 pandemic and airports and airlines cut staff across the U.S. and Europe.
Koenig reported from Dallas, and Chapman from New York. Associated Press writers Zeke Miller and Tara Copp in Washington, DC, Kelvin Chan in London, Tom Krisher in Detroit and Freida Frisaro in Miami contributed to this report.