ROB SCHMITZ, HOST:
What caused the cascade of failures which brought the U.S. air travel system to its knees on Friday? Transportation Secretary Sean Duffy's explanation - a contractor was replacing a router to upgrade the nation's outdated air traffic control equipment when something went very wrong.
(SOUNDBITE OF ARCHIVED RECORDING)
SEAN DUFFY: This was an FAA system that didn't meet the moment. Our contractor didn't meet the moment. Or the equipment didn't meet the moment and cause the outages.
SCHMITZ: The system is back online, and flights are now taking off, but travelers throughout the country are still dealing with the disruption. NPR spoke to one traveler, Andres Martinez Murillo, last night.
ANDRES MARTINEZ MURILLO: My flight keeps getting delayed further. They don't know if it's, like, a crew issue. They don't know if it's, like, a pilot issue. I don't even know if we have a plane.
SCHMITZ: Murillo told NPR he finally boarded his first flight this morning, but his second flight's been canceled, and he still does not know when he will reach his final destination. For more, we're joined by NPR transportation correspondent Joel Rose. Hey, Joel.
JOEL ROSE, BYLINE: Hey, Rob.
SCHMITZ: So many angry passengers today that still have not gotten to their destinations - what more do we know about the cause of all of this?
ROSE: We are starting to get a clearer picture. The heads of the Department of Transportation and the Federal Aviation Administration held a press conference today, and they put the blame squarely on a longtime FAA contractor, L3 Harris Technologies. They say the company was doing a routine maintenance upgrade of a server as part of a transition from older copper wire to fiber optic cable, and that is when things went sideways.
Sean Duffy and FAA leaders were asked several times why a faulty router could lead to telecom outages across such a wide part of the country. They said that is still under investigation. In a statement, L3 Harris says it is supporting the FAA's investigation into what went wrong and that it takes the impact on airlines and travelers seriously.
SCHMITZ: OK. Let's step back here just for a moment. What was happening in the air while all of this was playing out on the ground?
ROSE: Air traffic controllers were starting to see intermittent problems with radar and communication systems around 3:30 p.m. Eastern. By 3:44 p.m., the FAA declared a nationwide ground stop. Here is some of the reaction from air traffic controllers and pilots in Salt Lake City, as you can hear in archived audio from the website, liveatc.net.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED PERSON #1: You guys got any updates from your company about what's going on?
UNIDENTIFIED PERSON #2: Not at all. If you've got info, we're all ears.
UNIDENTIFIED PERSON #1: I wish we did. We basically only know what the FAA tells us, which is not a lot.
ROSE: I talked to one air traffic controller who was working when the outage began. He is a controller at one of the en route centers that handle high altitude traffic and was not authorized to speak publicly, but he described the situation as chaos. He said, a lot of airplanes were being diverted away from their original destinations. Some of them were running out of fuel. And he emphasized just how this whole system depends on the air traffic controllers, who found a way to more than 3,000 planes onto the ground quickly and safely, even when their equipment was letting them down.
SCHMITZ: So we've got a lot of confused pilots, a lot of confused air traffic controllers. You know, I'm just curious, the air traffic controller that you spoke to - did he have any thoughts about the apparent cause of this ground stop?
ROSE: I should say that we spoke this morning before the press conference by DOT, but this controller was already beginning to think that this was probably a mistake by a contractor who was doing work to upgrade the air traffic control system, which this controller says is happening all the time. He also places some of the blame on the oversight of the FAA for not having enough redundant systems in place, you know, to prevent this kind of outage from happening. He questioned why this work was going on in the middle of a busy Friday afternoon instead...
SCHMITZ: Right.
ROSE: ...Of late at night when it would not have had as much impact if something went wrong. He said it, quote, "just screams incompetence, like, gross incompetence."
SCHMITZ: You know, it does seem quite remarkable that a single point of failure like this could have such an enormous impact. What has the FAA said about this?
ROSE: Well, they said this was considered routine maintenance work. They are still investigating why it appears to have basically broken the entire national airspace. Here is Rebecca Guy, the acting chief technology officer at the FAA.
(SOUNDBITE OF ARCHIVED RECORDING)
REBECCA GUY: What we are doing is that root cause analysis, but at this time, we do believe what occurred with that router has been worked through.
ROSE: In other words, they think they have solved the problem. The FAA administrator promised that things should be back to normal by close of business on Sunday.
SCHMITZ: That is NPR transportation correspondent, Joel Rose. Joel, thank you so much for all that reporting.
ROSE: You're welcome. Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
