The world’s largest airline fleet was grounded for several hours Wednesday due to a technical glitch in a government system that forced the cancellation or delay of thousands of flights across the United States.
The White House initially said there was no evidence that it was a cyberattack. President Joe Biden indicated Wednesday morning that he instructed the Department of Transportation to investigate what happened.
Whatever the cause, the chaos revealed just how dependent the world’s largest economy is on air travel, and how dependent air travel is on an antiquated system called the Notification of Air Missions (NOTAM) system.
Before taking flight, pilots have to consult the NOTAM, which warns them of potential problems, such as take-off runways under construction or icing conditions. The system used to be by phone and the pilots called flight stations to get the information, but currently it is online.
The NOTAM stopped working on Tuesday night, causing more than 1,100 flights to be canceled and 7,700 delayed by midday on Wednesday, according to the specialized website FlightAware.
The chaos is expected to escalate as the repercussions are felt. More than 21,000 flights were scheduled to take off from the United States on Wednesday, most of them domestic, and there were about 1,840 international flights bound for the United States, according to data firm Cirium.
Airports in Chicago, Los Angeles, New York and Atlanta reported that between 30% and 40% of their flights were delayed.
“We’re going to see the effects of that as the delays this morning ripple through the day,” Transportation Secretary Pete Buttigieg said in an interview with CNN. “Now we need to understand how this could have happened at all. Why the backup mechanisms that would normally have prevented this from being so disruptive didn’t prevent it from being so this time around.”
Veteran aviation experts could not remember a collapse of this magnitude that was caused by a technical failure. Some compared it to the total closure of the national airspace after the terrorist attacks of September 11, 2001.
“Local issues have periodically occurred here or there, but this is historically significant,” said Tim Campbell, a former vice president of air operations for American Airlines who now works as a consultant in Minneapolis.
Campbell explained that there has long been consternation about Federal Aviation Administration (FAA) technology, not just NOTAM.
“They have a lot of old systems that are generally reliable, but they’re outdated,” he said.
John Cox, a former airline pilot and aviation safety expert, said there had been talk in the aviation industry for years about attempts to modernize the NOTAM, but he stressed that he was not aware of the age of the servers used by the FAA.
He could not say if it could have been a cyberattack.
“I’ve been flying airplanes for 53 years and I’ve never seen a collapse like this,” Cox said. “So something unusual has happened.”
According to FAA data, the NOTAM went down at 8:28 p.m. Tuesday ET, preventing pilots from receiving new or updated reports. The FAA turned to a dedicated phone line to keep flights in the air overnight, but as the volume of flights increased during the day, the phone system became overwhelmed.
On Wednesday morning, the FAA ordered all planes to be grounded, affecting both passenger and transport flights.
Some medical flights were approved and the blackout did not affect military flights.
For its part, the White House initially said there was no evidence of a cyberattack. However, President Biden commented that ”we don’t know” and told reporters that he directed the Department of Transportation to investigate the cause of the outage.
“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 let me know directly when he found out. Air traffic may still land safely, but not take off at this time. We don’t know what is the cause of this.”
Julia Macpherson was on a United Airlines flight from Sydney to Los Angeles on Wednesday when she learned of the delays.
“When I was in the air, I heard from a friend who was also traveling overseas that there was a glitch,” said Macpherson, who was returning to Florida from Hobart, Tasmania. He was due to fly first to Los Angeles, then go to Denver for a connecting flight to Jacksonville, Florida.