What was supposed to be a quiet start to the holidays for thousands of Americans turned into utter chaos. On the night of August 6, United Airlines experienced a critical failure in its internal system that paralyzed all its flights nationwide. The problem began shortly after 6 p.m. Eastern Time, leaving passengers bewildered, stranded in airports, or even stuck inside planes.
The airline clarified that it was not a cyberattack. The cause was a failure in its Unimatic system, which manages key safety data such as aircraft weight and distribution. Without this information, it was impossible to guarantee the safety of operations.
Chaos at key airports
The impact of the failure was strongly felt at airports like Chicago O’Hare, Denver, San Francisco, Newark, and Houston. At its peak, more than 1,000 flights were delayed and 218 were canceled, about 35% of United Airlines departures.
Many passengers described long hours of waiting, frustration, and confusion. A couple traveling to Dallas spent 16 hours in Denver before they could reach their destination. A child became ill while waiting on a plane in high temperatures.
Just like in the movie The Terminal, hundreds of people found themselves trapped with no way to move forward to their destinations.
United Airlines's response
United offered food and hotel vouchers, and flight rescheduling without penalty before August 16. The company insisted that safety remained the priority and reiterated that the problem was not related to cybersecurity.
Despite these measures, delays persisted for days. At some airports, such as San Francisco, United claimed that delays hovered around 25% with no cancellations reported, although external figures showed a different reality.
Lessons and recommendations for travelers
Although by August 11 most flights had resumed operations, delays and irregular schedules were still being reported. This incident left clear lessons for travelers:
- Use the airline's app or website to reschedule flights quickly.
- Request a written delay notice, which is useful for future claims.
- Ask for a refund instead of rescheduling if the delay exceeds three hours.
- Claim food and accommodation vouchers if the interruption is the airline's responsibility.
- Keep receipts and screenshots of all communications.
Although United Airlines has already rescheduled its flights, this incident serves as a clear reminder: even the most carefully planned vacations can be affected by technical failures. The airline will need to update Unimatic to prevent a failure from paralyzing operations and affecting thousands of passengers.