With air travel gradually resuming, passengers still face ripple effects from the nationwide ground stop issued by the Federal Aviation Administration (FAA) early Wednesday morning. One Chicago traveler spoke out after getting stuck at the Chicago O'Hare International Airport.
"Now it's all backed up. This is insane. And is this going to be traumatizing, especially with three kids, it's going to be traumatizing," the traveler told FOX Business' Grady Trimble.
The outage began early Wednesday morning when the FAA's Notice to Air Missions (NOTAM) system went down. NOTAM is a safety system that alerts pilots and other personnel about airborne issues and other delays at airports across the country.
Due to the outage, the FAA ordered a pause on all domestic flights until 9 a.m. ET "to allow the agency to validate the integrity of flight and safety information."
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The Chicago passenger shared his surprise after learning his experience was part of a nationwide issue.
"That's crazy. This is scary. That's even scarier, bro," he said.
Earlier in the morning, a couple told a FOX reporter in Philadelphia that their flight to Florida to catch a cruise was grounded after making it to the tarmac for takeoff. They said on "Fox & Friends" that the airline's website listed their flight as being "on time" despite passengers having exited the plane.
Flights have since resumed across the country and the FAA announced they plan to investigate what caused the initial system collapse.
Transportation Secretary Pete Buttigieg responded to the outage assuring Americans his department plans to investigate and "determine root causes."
"I have been in touch with FAA this morning about an outage affecting a key system for providing safety information to pilots," Buttigieg wrote on social media Wednesday morning. "FAA is working to resolve this issue swiftly and safely so that air traffic can resume normal operations, and will continue to provide updates."
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"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," he wrote later. "I have directed an after-action process to determine root causes and recommend next steps."
Aviation expert Kyle Bailey argued "overload" may have caused the system failure.
"Typically, the government systems are a bit antiquated and there's just so many data points that are layered that are coming into the system. This is basically every single airport in the country, and it's getting data from around the world, not just big airports, but small airports, too," Bailey said on "America's Newsroom" Wednesday. "So it basically was pretty much an overload, I think."
Bailey also explained that the NOTAM system is "critical to safely landing and taking off" as well as any dangers en route. So without the functioning system, pilots cannot foresee if a route is safe for passengers.
Despite uncertainty about what caused the outage, Bailey said his "gut feeling" was that this ordeal was not hacking or terror-related. The White House also said in a tweet Wednesday morning they did not see evidence of a cyberattack.
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The U.S. has been no stranger to travel woes over the past two months, and this incident has only added more pressure on Buttigieg. As flights across the country attempt to return to schedule, Americans are still demanding an explanation.
Fox News' Timothy H.J. Nerozzi and Danielle Wallace contributed to this report.
