A computer outage that grounded some United Airlines flights has been resolved.
More than 1,000 flights were delayed on Wednesday night after the computer system Unimatic was impacted. The system, according to The Associated Press, compiles flight information that is then used by other systems to calculate weight and track flight times.
Another 40 were canceled, ABC News reported. United Express and flights already in the air were not affected.
About 34% of flights were delayed by the outage, Reuters reported.
The undisclosed issue was resolved late Wednesday night.
The airline said Wednesday evening, “Due to a technology issue, we are holding United mainline flights at their departure airports 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,” ABC News reported.
The Federal Aviation Administration said flights headed to Chicago were held at their originating airports, as were flights to Denver, Newark, Houston and San Francisco, the AP reported.
Officials said the issue was not a cybersecurity incident.
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