FAA says contractors to blame for grounding of domestic flights

Jan. 20 (UPI) -- The Federal Aviation Administration said Thursday that private contractors inadvertently caused the meltdown of its Notice to Air Missions system that grounded all domestic flights for hours earlier this month.

The agency said the preliminary review of the Jan. 11 incident found the outage occurred when "contract personnel unintentionally deleted files while working to correct synchronization between the live primary database and a backup database."

The agency also said it had "so far found no evidence of a cyberattack or malicious intent," adding it would continue to investigate the incident.

"The FAA made the necessary repairs to the system and has taken steps to make the NOTAM system more resilient," the FAA said.

The day after the incident, the FAA said the outage was caused by a single corrupted file.

The NOTAM indicates alerts pilots and airports of real-time hazards in the National Airspace System.

The failure prompted the agency to make the rare decision to ground all domestic flights leading to more than 1,000 cancelations and about 10,000 delays.

Following the incident, Transportation Secretary Pete Buttigieg said he would work with the FAA to determine whether the system is outdated.

"The agency is acting quickly to adopt any other lessons learned in our efforts to ensure the continuing robustness of the nation's air traffic control system," the FAA said Friday.