Chicago, IL — A nationwide ground stop on United Airlines mainline flights Wednesday night caused widespread disruption, with more than 1,000 delays and dozens of cancellations, following a technical failure in a key internal system, the airline confirmed.
Weight and Balance System Failure Halts Operations
According to ABC News, the issue began shortly after 6 p.m. ET and originated from a problem with United’s weight and balance computer system, which is critical for safe takeoffs and flight operations.
“Due to a technology issue, we are holding United mainline flights at their departure airports,” the airline said in a statement. “We expect additional flight delays this evening as we work through this issue. Safety is our top priority, and we’ll work with our customers to get them to their destinations.”
The ground stop did not affect United Express flights, and planes already airborne continued to their destinations as planned.
Delays Across Major United Hubs
According to FlightAware, over 1,000 United flights were delayed, and more than 40 flights were canceled due to the outage. The Federal Aviation Administration (FAA) said it was aware of the technology issue and that it was limited to United’s systems.
Multiple FAA bulletins confirmed that ground stops were requested by United at key hubs, including:
- Newark Liberty International Airport
- San Francisco International Airport
- Chicago O’Hare
- Denver International
- Houston George Bush Intercontinental Airport
“The issue was specific to United’s operations and is unrelated to the broader air traffic control system,” said U.S. Transportation Secretary Sean Duffy in a statement shared by ABC News.
Not a Cyberattack, Says United
United Airlines confirmed the incident was not caused by a cyberattack, addressing early speculation online. The issue was resolved within a few hours, but residual delays continued to ripple across the airline’s domestic and international schedule.
To support stranded travelers, United announced it would:
- Cover meal and hotel expenses for impacted passengers
- Work to rebook customers as quickly as possible through digital apps and airport staff
Growing Concerns About Airline Tech Infrastructure
Wednesday’s outage is the latest in a string of technology-related disruptions affecting major U.S. airlines in recent years. Experts say aging infrastructure and growing digital complexity increase the risk of groundings like this one.
“While the system has been restored, we may still see delays as operations reset,” United said in its latest update.
Travelers are advised to check their flight status before heading to the airport and monitor United’s app and website for the latest rebooking options.
Were you affected by the outage? Share your travel experience in the comments.
