The Federal Aviation Administration (FAA) has said that yesterday's flight chaos in the US was caused by a corrupted database file. A similar issue appears to have hit Canada later in the day.

After an overnight outage in the Notice to Air Missions (NOTAM) system, which provides essential safety updates, the FAA grounded all domestic US flights for nearly two hours early Wednesday morning. Flights took some time to return to normal, with more than 1,300 flights canceled and 10,000 delayed. The delays affected more than half the flights from airports like Denver International, and New York's LaGuardia.

Delta Air Lines plane
– Delta Air Lines

In Canada, the FAA's equivalent body, NAV Canada, also had NOTAM troubles tweeting at 1215 ET that it was suffering an "outage affecting newly issued NOTAMs".

NAV Canada said the outage lasted from 10:20 ET to 13:15 ET, and caused no delays or cancellations. Surprisingly, the body said it did not believe the two outages were related.

Back in the US, at 18:30, the FAA issued a statement, saying it had traced its outage to a "damaged database file", but was continuing to look for the root cause, having found no evidence of a cyber attack.

"The FAA is working diligently to further pinpoint the causes of this issue and take all needed steps to prevent this kind of disruption from happening again," the statement concluded.

The corrupted file affected both the primary and the backup systems, a senior government official said Wednesday evening, and Government officials will be looking into how the NOTAM system can be made more resilient, reports NBC News.

It is not yet clear what compensation will be offered to travelers and who will pay it. Normally airlines pay compensation, but in this case, the cause was a service provided by the government-run FAA. Transportation Secretary Pete Buttigieg did not say whether the Transportation Department would pay compensation when asked by a reporter.

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