Ground stop at MSP after air traffic control outage

A ground stop at Minneapolis–St. Paul International Airport on Thursday followed an apparent outage at the regional air traffic control center, disrupting flights across the Upper Midwest and forcing airlines to delay or divert aircraft for several hours.

Radar and communications failure halts traffic at MSP

Publicly available flight tracking data and passenger accounts indicate that air traffic in and out of Minneapolis–St. Paul International Airport largely came to a standstill on Thursday afternoon after a technical failure at the Minneapolis Air Route Traffic Control Center, known as ZMP.

Reports from aviation tracking communities and social media described a sudden gap in high altitude traffic over Minnesota and the Dakotas, followed by confirmation that Minneapolis Center had lost access to key radar and communications systems. The disruption led to the declaration of an “ATC Zero” situation at the facility, meaning it could no longer safely provide normal air traffic services across its airspace.

Information shared by travelers and airline staff suggests the outage began in the early afternoon, around 2:00 p.m. Central Time, and persisted in various forms for roughly two hours before services were gradually restored. During the most intense phase, aircraft bound for Minneapolis and overflying the region were rerouted, held or diverted, while departures to the affected airspace were temporarily barred from taking off.

Ground stop triggers delays and diversions across the region

According to flight status boards and tracking platforms, the ground stop at Minneapolis–St. Paul quickly rippled across the national airspace system. Passengers reported aircraft returning to gates after pushback, extended waits on taxiways, and diversions to airports as far away as Nebraska and Colorado as routes through the affected airspace were restricted.

Multiple airlines appeared to hold flights on the ground at departure airports rather than allow them to depart into uncertain routing conditions. Travelers connecting through Minneapolis reported missed connections and rolling departure estimates as the outage continued and crews waited for air traffic control to reopen key sectors.

Even after initial restrictions were eased and routes began to reopen, congestion persisted as airlines worked through a backlog of delayed flights. Some sectors of airspace were reportedly reopened before others, meaning departures in certain directions resumed while flights bound for other regions remained under delay programs or ground holds.

Possible link to broader communications and internet issues

Local reports from the Twin Cities area on Thursday described concurrent internet and communications disruptions affecting parts of southern and central Minnesota. Residents, businesses and public institutions noted connectivity problems over roughly the same timeframe as the air traffic control issues.

Comments from aviation workers and technology observers suggest the Minneapolis Center outage may have been related to a failure at a major regional data facility or backbone provider, interrupting essential communications links used by the air traffic control system. While the precise technical cause has not been detailed in official releases, publicly shared information points to a loss of multiple services, including radar feeds and communications paths used to manage high altitude traffic over a wide, multi-state area.

The Minneapolis Air Route Traffic Control Center oversees a vast swath of airspace that includes portions of Minnesota, Wisconsin, Iowa, North and South Dakota and neighboring states. When that facility experiences an ATC Zero event, flights across hundreds of thousands of square miles can be affected, making a local equipment issue a national concern for airlines and passengers.

Understanding ground stops and ATC Zero events

Ground stops are traffic management tools used within the U.S. airspace system to slow or halt the flow of aircraft to specific airports or regions when conditions prevent safe normal operations. They can be triggered by severe weather, runway closures, or, as in this case, an equipment or systems outage affecting air traffic control services.

During a ground stop, aircraft meeting certain criteria are required to remain on the ground at their departure airports until the restriction is lifted or modified. Flights already airborne may be rerouted, slowed or held in holding patterns, or diverted to alternate airports if necessary to keep them clear of the affected airspace and maintain safety margins.

An ATC Zero declaration at an air traffic control facility signals that controllers there cannot safely provide the services normally required for instrument flight operations. Other centers and adjacent facilities may take on limited responsibilities, and traffic volume through the affected area is sharply reduced or paused until systems are restored and staffing and procedures are verified.

Aftermath and implications for travelers

As systems at Minneapolis Center came back online later Thursday, traffic management initiatives transitioned from full ground stops to more targeted flow controls, and flight activity over Minnesota gradually returned toward typical patterns. However, passengers reported lingering delays into the evening as aircraft, crews and schedules were realigned.

The event highlights how dependent modern air travel is on the continuous functioning of complex radar, communications and data networks. A single regional outage can quickly affect dozens of airports and thousands of travelers, even in clear weather, simply because aircraft cannot safely be separated and sequenced without the usual tools and connectivity.

For travelers, the episode serves as a reminder that technical disruptions can materialize with little warning and that even well-practiced contingency plans may still result in significant delays. Airlines typically prioritize safety and regulatory requirements in responding to such events, which can mean holding flights on the ground, consolidating services, or rerouting passengers through alternative hubs when a key control center is constrained.

Operational data over the coming days is expected to show the full scale of Thursday’s disruption, including numbers of delayed and diverted flights. For now, the Minneapolis outage stands as one of the more significant recent examples of how a localized air traffic control failure can reverberate across the wider U.S. air travel network.