The US Federal Aviation Administration (FAA) has linked the Notice to Air Missions (NOTAM) system outage, which disrupted thousands of flights to a ‘damaged database file’.

NOTAM alerts pilots on hazards along a flight route.

The malfunction was caused by a procedural error related to a data file, which corrupted both the main system and its backup, Reuters reported citing people with knowledge of the review.

The FAA said it has no evidence of a cyber-attack.

How well do you really know your competitors?

Access the most comprehensive Company Profiles on the market, powered by GlobalData. Save hours of research. Gain competitive edge.

Company Profile – free sample

Thank you!

Your download email will arrive shortly

Not ready to buy yet? Download a free sample

We are confident about the unique quality of our Company Profiles. However, we want you to make the most beneficial decision for your business, so we offer a free sample that you can download by submitting the below form

By GlobalData
Visit our Privacy Policy for more information about our services, how we may use, process and share your personal data, including information of your rights in respect of your personal data and how you can unsubscribe from future marketing communications. Our services are intended for corporate subscribers and you warrant that the email address submitted is your corporate email address.

On its website, the FAA said: “The FAA is continuing a thorough review to determine the root cause of the Notice to Air Missions (NOTAM) system outage. Our preliminary work has traced the outage to a damaged database file. At this time, there is 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 technical glitch, which happened on Wednesday, delayed or cancelled over 11,300 flights, in what is reported to be the first national grounding of domestic traffic in nearly 20 years.

Following an overnight outage, the FAA lifted the grounding order and normal air traffic operations resumed gradually across the country.

Reuters reported that Delta Air Lines, United Airlines, American Airlines Group and Southwest Airlines have all resumed normal operations on Thursday.

However, 5,109 US flights were delayed and 163 were called off as of 7pm EST Thursday, according to flight tracking data company FlightAware.

The FAA estimates flight cancellations on Thursday to be less than 1%.