United Airlines Cancel And Delay Over 650 Flights In Us As Travel Disruption Continues In The Wake Of A It Outage, Including Denver, Miami, Houston, Los Angeles, Chicago, And More

Published on August 8, 2025 |

By: TTW News Desk

A crippling IT outage sent United Airlines and its passengers into a two-day spiral of recreation chaos this week, pinch nan fallout from nan resolved glitch continuing to disrupt operations crossed nan US done Thursday. The nonaccomplishment of nan airline’s captious “Unimatic” formation accusation strategy connected Wednesday triggered a logistical meltdown that yet impacted complete 1,700 flights. While nan strategy was restored Wednesday night, nan hose continued to struggle pinch displaced craft and crews, resulting successful 164 cancellations and 489 delays connected Thursday alone. This compounded nan turmoil from nan first outage connected Wednesday, which saw 218 flights cancelled and astir 1,100 delayed, leaving thousands of passengers stranded astatine awesome hubs including Chicago, Denver, Houston, and Los Angeles.

As of Today, departure boards successful United’s awesome hubs were still a oversea of red, pinch 164 flights cancelled and different 489 delayed. This operational paralysis was nan nonstop consequence of a acold much aggravated breakdown connected Yesterday, erstwhile nan strategy nonaccomplishment first occurred, starring to 218 cancellations and a staggering 1,100 delays.

A monolithic two-day recreation meltdown engulfed United Airlines this week aft nan nonaccomplishment of its captious “Unimatic” IT system, yet disrupting complete 1,700 flights. The chaos peaked connected Wednesday erstwhile 218 flights (7%) were cancelled and astir 1,100 flights (35%) were delayed. The logistical fallout continued to plague nan hose done Thursday, wherever different 164 flights (5%) were cancelled and 489 flights (15%) were delayed arsenic nan bearer struggled to reposition craft and crews. This wide disruption was felt crossed nan full network, impacting routes of each types, from awesome world services for illustration UAL146 betwixt Newark and London, to cardinal cross-country connections specified arsenic UAL796 from San Francisco to Boston and UAL2276 from Los Angeles to Chicago, and moreover shorter location hops for illustration UAL1476 from Denver to Kansas City, leaving thousands of passengers stranded astatine its awesome hubs.

The Anatomy of a Meltdown: A Legacy System Fails

At nan bosom of nan situation was a nonaccomplishment successful United’s “Unimatic” system. This is simply a “legacy system”—older but basal package that acts arsenic nan integer backbone for nan airline’s formation operations. It houses nan foundational information for astir each flight, including routing information, formation times, and captious weight and equilibrium calculations needed for safe takeoff.

When Unimatic went down for respective hours Wednesday night, it was for illustration a nervus halfway being severed. Though IT teams managed to resoluteness nan outage by precocious evening, nan harm was already done. The incident, which United confirmed was not a cybersecurity breach, triggered a logistical domino effect that would return days to untangle.

The cardinal problem is that a resolved IT rumor doesn’t instantly put craft and formation crews backmost wherever they request to be. A level that was scheduled to alert from Chicago to Los Angeles connected Thursday greeting mightiness person been nan aforesaid craft that was stuck connected nan tarmac successful Denver nan nighttime before. Similarly, a formation crew’s legally mandated work hours whitethorn person expired while they waited for a resolution, making them ineligible to aviator their adjacent scheduled flight. This cascading nonaccomplishment of positioning and scheduling is why nan disruptions continued agelong aft nan servers were backmost online.

Response and Nationwide Impact

As nan situation unfolded, nan Federal Aviation Administration (FAA) stepped in, issuing a crushed extremity that halted United flights destined for its Chicago hub to forestall nan airdrome from being wholly overwhelmed. The effect was felt crossed nan full network, affecting flights of each types. Major cross-country services for illustration UAL796 from San Francisco to Boston and cardinal hub connections specified arsenic UAL2276 from Los Angeles to Chicago faced important delays. The problems extended to world gateways, pinch flights for illustration UAL146 from Newark to London Heathrow caught successful nan snarl. Even shorter location routes, including UAL2074 from Denver to Rapid City, were not immune, illustrating really nan nonaccomplishment of a azygous strategy could paralyze an full network.

United’s nationalist relations squad worked to negociate nan fallout, issuing statements apologizing for nan disruption and reaffirming that information was its apical priority. The hose assured customers it was moving to rebook them and would screen expenses for illustration hotels and meals successful accordance pinch its policies.

Now, arsenic nan hose useful to clear nan backlog and reconstruct a normal schedule, its larger situation will beryllium to reconstruct nan assurance of nan thousands of passengers who were caught successful nan crossfire of a little but catastrophic strategy failure.