Old System, Data Overload: What Led To US Grounding Over 8,000 Flights

New Delhi: The US witnessed a rare, brief grounding of departing flights - the second such incident since 9/11 - last night, leaving lakhs of passengers distressed at all airports across the country. The shutdown order was issued citing "extraordinary circumstances and reasons for safety". The halt, which reportedly grounded over 8,000 flights carrying 15 lakh fliers, was lifted today morning after the US authorities received the clearance of a possible threat and nefarious attack.The ground stop lasted around four hours and was lifted at 8:15 pm (EST) -- 6:45 am (IST).What exactly happened?The Federal Aviation Administration (FAA) at 3:54 pm (EST) -- around 2:24 pm (IST) -- issued a nationwide ground stop for all departing flights from the US. In a later advisory, it identified the reason for the restrictions as a telecommunications outage affecting air route traffic control centres.The aircrafts already in air were allowed to continue to their destinations and land during the shutdown.What is a nationwide ground stop?A nationwide ground stop is an emergency air traffic control measure issued by the FAA that temporarily stops all new or scheduled domestic departures across the country.While a standard ground stop usually applies to a single airport or regional airspace, a nationwide shutdown is rare.There was one such stop in January 2023 when a pilot notification system failed, but the only other national stop happened in the wake of the 9/11 attacks in September 2001, when no aircraft flew for days.What caused the telecommunications failure?US Secretary of Transportation Sean Duffy said that the flight outages were caused by "old systems getting overloaded with data"."This is a legacy system problem. We have old, old switches, old routers. We use 1980s little copper lines. It's an old system that went down, and went down everywhere. It got overloaded," he said.According to him, the US Congress is to be blamed as it did not fund a full package to get it replaced."Do you want Congress to fund this? President Trump has asked for the money. This is analog telecom. Our switches, our routers actually got overloaded with data, and they went down. And I shouldn't say they went down, they started to give us inconsistency in the data from those routers. And because of that, we shut the system down," he said.Demanding money to fix the systems, Duffy said, "Give us the resources to build a state-of-the-art air traffic control system. Let's not do a patchwork fix to a system that's critical for every single family. It's not red, it's not red, it's not blue, it's not Democrat, it's not Republican, it's American. Give us the money to fix it".Ground stop lifted, no 9/11-like threatUS Secretary of Homeland Security Markwayne Mullin ruled out the possibility of another 9/11-like attack and also said there was no connection between the recent Microsoft outage and the ground stop."Welcome to Friday the 13th, right? You know, I wanna make sure everybody understands that there is no connection between this and Microsoft. I know a lot of people are making that jump. This is so far what we've seen, there is actually no cyberattack...This isn't another 9/11," he said.Mullin assured the passengers that the US government is working with the airports, communities, cities, and states to make sure everyone is safe."FEMA (Federal Emergency Management Agency) has activated their centers to make sure that there's no medication that is being missed. If it is, we're going to have people for them to reach out to. The airport has got a direct number to reach out to us. We can provide that medication for them, working through the state. So right now things seem to be working, as we can say, in the right direction," he added.Passengers distressedFor many passengers, their family plans and work journeys were disrupted.At New York's Kennedy Airport, Riley Alexis Holmes had hoped to fly to Oregon in time for her brother's musical closing night. Instead, after nearly two hours of delay, her flight was cancelled."I called my mom and cried, and I'm just sitting here waiting for information," she said.Another passenger said, "I feel very frustrated because you know, you come to the airport and then all of a sudden your whole plans have changed and you don't know when you're leaving, We're kind of stuck."In New York's busy LaGuardia Airport, Janice Llewellyn was on the verge of tears: The chaos could mean she will miss her daughter's wedding in Toronto. "I may lose my mind...My husband flew all the way from England to get to the wedding. Oh gosh! I wish they had another flight, I wish I could get another flight, like, now," she said.In Florida, Gainesville Regional Airport ordered pizza for about 80 passengers who were stuck due to the shutdown.When will flights return to normal?While the ground stop was lifted off, passengers are still likely to face delays or cancellations as airlines reposition aircraft and crews.Duffy, in a statement, said that it will take "some time to get back to capacity", but he expected operations to be "back up and operational as we come into the heat of travel during Thanksgiving".The Thanksgiving travel period, which begins in less than two weeks, is usually one of the busiest times of the year for air travel in the US.Airlines have advised its passengers to check their flight status directly with their airlines, as delays and cancellations might continue.