Why did FAA declare nationwide ground stop of all flights today? What could be the possible cause? Has this happened in the US before?
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The FAA grounded every departing flight in the US this afternoon because a telecommunications failure knocked out communications across all Air Route Traffic Control Centers, the facilities that guide planes at high altitudes. Flights already airborne were allowed to land, but no new departures were permitted until further notice. The investigation is live and no cause has been confirmed.
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spio.comWhat happened
The FAA issued a nationwide ground stop at 3:54 PM EST due to a communication outage. The communications issues were described as "impacting multiple Air Route Traffic Control Centers," the facilities that guide airplanes at high altitudes along their routes. Airlines confirmed that flights already in the air would continue to their destinations.
The ground stop affected more than 10,000 flights and led to more than 1,000 cancellations. International flights transiting US airspace were also affected.
What caused it
The official answer right now is: a telecommunications outage, and not much more. Multiple sources told CBS News that an update to the private communications network connecting America's air traffic control system caused that system to reboot, leading to a crash and a communications outage. The system is operated by L3Harris, which had not responded to comment requests at the time of reporting.
The Washington Examiner reported it may be the result of a "frequency outage." An internal message from Alaska Airlines, seen by CNBC, described the issues as related to both communications and radar problems.
One wrinkle worth watching: three days earlier, the FAA had expanded an AI air traffic management system called SMART (Strategic Management of Airspace, Routes and Trajectories) to all air centers. The FAA has denied this as a cause. Officials also said the ground stop was not linked to this week's disruptive Microsoft global outage.
Homeland Security Secretary Markwayne Mullin said there was "no indication yet that this was a nefarious attack." As of this evening, the exact cause remains unclear.
Has this happened before?
Yes, but very rarely. This is only the second nationwide ground stop since the September 11, 2001 attacks. The first was in January 2023, when a key FAA computer system malfunctioned. That 2023 event was caused by a failure of the FAA's NOTAM system, which stands for Notice to Air Missions, the safety alert system pilots rely on before takeoff. An aviation safety expert noted that the problem appeared similar to a regional air traffic control communication outage earlier that caused hundreds of flight disruptions across the Northeast, except this time it hit the entire country.
So in the last 25 years, every plane in America has been grounded exactly twice, counting today. That is how rare this is, and why investigators and lawmakers are already calling for answers. Senator Tammy Duckworth called for a "thorough and complete" investigation.
Follow-ups
Was the FAA ground stop done to force Congress to foot the $50 billion bill?
There is no evidence of that. Officials blame an update to the FAA's private communications network that set off a reboot and a crash, and they ruled out any deliberate interference. But the timing helped the administration's case: it came 7 weeks after Secretary Sean Duffy asked Congress for $30 billion more, and offi
There is no evidence of that. Officials blame an update to the FAA's private communications network that set off a reboot and a crash, and they ruled out any deliberate interference. But the timing helped the administration's case: it came 7 weeks after Secretary Sean Duffy asked Congress for $30 billion more, and officials used it right away to push for funding, now put at about $50 billion in all.
spio.comWhat Happened
On Friday, November 13, 2026, at about 3:54 PM Eastern time, the FAA stopped every departing flight at every US airport. It lifted the stop at about 8:15 PM, after more than 4 hours. More than 4,700 flights were canceled and 10,000 delayed, and Reuters called it the longest nationwide grounding since September 11, 2001.
What Officials Say Caused It
- Multiple sources told CBS News that an update to the private network linking the air traffic control system set off a reboot, which then crashed. That network is run by the contractor L3Harris.
- Transportation Secretary Sean Duffy said routers carrying air traffic data were overloaded and gave inconsistent information, and blamed "an incredibly old air traffic control system."
- Homeland Security Secretary Markwayne Mullin said there was no sign of a cyberattack or deliberate interference.
Why Some People Suspect It
- The timing. On September 28, 2026, Secretary Duffy asked Congress for $30 billion more for air traffic control, on top of $12.5 billion approved in 2025. Some lawmakers were reluctant. Weeks later, the whole country saw the system fail.
- How fast it became a funding pitch. Within hours, officials were saying a full overhaul could cost about $50 billion.
- A familiar playbook. Many people believe leaders let a crisis make the case for money they already wanted.
Why the Evidence Points the Other Way
- Deliberately shutting down US air travel would put lives at risk, break federal law and be very hard to hide, since the system is run by thousands of controllers and outside contractors.
- The cause officials describe, a botched network update, matches failures that have happened before. A contractor deleting files brought down a pilot alert system and stopped flights nationwide in January 2023, and an August 2026 failure at the Minneapolis center grounded flights across 9 states.
- Government auditors had warned for years that most of the FAA's systems are out of date.
The Bottom Line
No one has shown that the outage was planned. What is clear is that it made the administration's funding case for it, and Congress will now face more pressure to pay. The cause is still under investigation.
Who runs the FAA's communications network, and what went wrong?
The network is run by the contractor L3Harris. Called the FAA Telecommunications Infrastructure, it carries secure voice and data between more than 4,400 FAA sites. Sources say an update to it set off a reboot that crashed, cutting communications to the centers that guide planes at high altitude. AT&T is now building i
The network is run by the contractor L3Harris. Called the FAA Telecommunications Infrastructure, it carries secure voice and data between more than 4,400 FAA sites. Sources say an update to it set off a reboot that crashed, cutting communications to the centers that guide planes at high altitude. AT&T is now building its replacement.
spio.comThe Network Behind Every Flight
Air traffic controllers depend on a private network that links radar sites, control towers and the 20 Air Route Traffic Control Centers, the facilities that guide planes at cruising altitude. It is called the FAA Telecommunications Infrastructure, and it carries secure communications between more than 4,400 FAA facilities. The contractor L3Harris runs it.
What Went Wrong
Multiple sources told CBS News that an update to this network set off a reboot, and the reboot crashed. Secretary Sean Duffy said routers became overloaded and sent inconsistent information. With communications down across the high-altitude centers, the FAA stopped all departures nationwide. L3Harris had not commented, and the FAA says the investigation is still under way.
What Comes Next
In August 2026, the FAA gave AT&T a first task order worth $74.3 million to lead a rebuild of the network, with the goal of finishing by the end of 2028. The outage will likely speed up that work and bring more scrutiny of how updates are tested before they go live.
How old is America's air traffic control system?
Much of it dates to the 1980s and 1990s. Some sites still use copper wire, paper flight strips and even floppy disks. Government auditors found that more than a third of the FAA's key systems are unsustainable, meaning they are too old to keep running reliably.
Much of it dates to the 1980s and 1990s. Some sites still use copper wire, paper flight strips and even floppy disks. Government auditors found that more than a third of the FAA's key systems are unsustainable, meaning they are too old to keep running reliably.
spio.comOld Parts Still in Use
- Many radar and communication systems were built in the 1980s and 1990s, and replacement parts are hard to find.
- Some facilities still use copper telephone wire, paper strips to track flights and floppy disks to move data.
- In 2024, the Government Accountability Office, Congress's watchdog, found that 51 of the FAA's 138 key systems were unsustainable, and dozens more were at risk.
Failures Before This One
- In January 2023, a damaged file in a pilot alert system stopped departures nationwide.
- In spring 2025, controllers handling Newark flights lost radar and radio contact for up to 90 seconds, more than once.
- In August 2026, a failure at the Minneapolis center grounded flights across 9 states.
- On November 13, 2026, a communications outage stopped every departure in the country for more than 4 hours.
Why It Hasn't Been Fixed
An earlier modernization effort called NextGen, started in the 2000s, cost billions and fell behind schedule. Air traffic control has to keep running every minute while it is upgraded, which makes replacing it slow, and funding has come in pieces. Secretary Sean Duffy said that at today's pace, replacing every control tower would take about 300 years.
What is the $50 billion air traffic control plan, and what has Congress paid for so far?
The plan is called the Brand New Air Traffic Control System. Congress approved $12.5 billion for it in 2025. In September 2026, Secretary Sean Duffy asked for $30 billion more, and after the ground stop, officials put the full cost of an overhaul at about $50 billion.
The plan is called the Brand New Air Traffic Control System. Congress approved $12.5 billion for it in 2025. In September 2026, Secretary Sean Duffy asked for $30 billion more, and after the ground stop, officials put the full cost of an overhaul at about $50 billion.
spio.comThe Plan
In May 2025, the Trump administration announced the Brand New Air Traffic Control System, a plan to replace radar, radios, networks and software across the country and build new control towers.
What Has Been Paid For
- In July 2025, Congress approved $12.5 billion in the One Big Beautiful Bill Act. The Transportation Department called it a "down payment" on a plan then estimated at $31.5 billion.
- In August 2026, the FAA hired AT&T to lead a rebuild of its communications network, starting with a $74.3 million order.
What Is Being Asked For Now
- On September 28, 2026, Secretary Sean Duffy asked Congress for $30 billion more: $10 billion for new systems and software, $10 billion for towers, runways and taxiways, and $10 billion for mid-sized airports. That would bring the total to $42.5 billion.
- Senator Eric Schmitt introduced the Modern Skies Act to approve the money.
- After the November 13 ground stop, officials said a full overhaul could cost about $50 billion.
Where Congress Stands
Some lawmakers are wary after the earlier NextGen program ran over budget. The ground stop has put new pressure on Congress to act, and Secretary Duffy says the core upgrades could be done by 2028 if the money comes through.
Can you get a refund when the FAA grounds flights?
Yes, if your flight is canceled or badly delayed and you choose not to travel. Under US rules, airlines must give a full cash refund automatically, whatever the cause. But because a ground stop is outside the airline's control, airlines are not required to pay for meals or hotels, though many waive change fees.
Yes, if your flight is canceled or badly delayed and you choose not to travel. Under US rules, airlines must give a full cash refund automatically, whatever the cause. But because a ground stop is outside the airline's control, airlines are not required to pay for meals or hotels, though many waive change fees.
spio.comYour Right to a Refund
Under US Department of Transportation rules, you are owed a full refund to your original form of payment when:
- Your flight is canceled and you don't accept another flight or a voucher.
- Your flight is delayed by 3 hours or more for a domestic trip, or 6 hours or more for an international one, and you choose not to fly.
The refund must be automatic: within 7 business days for a credit card and 20 days for other payments. You don't have to accept a travel credit if you want your money back.
What You May Not Get
Meals, hotels and cash compensation are generally owed only when the airline caused the problem, such as a crew or maintenance issue. A ground stop ordered by the FAA is outside the airline's control, so those extras are up to each airline.
What to Do Now
- Check your airline's app for a travel waiver, which lets you change dates without a fee.
- If your flight was canceled and you no longer want to go, ask for a refund, not a credit.
- Keep your receipts in case the airline offers to cover costs.
- If the airline won't refund you, file a complaint with the Department of Transportation at transportation.gov.
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