The Federal Aviation Administration said on Thursday that the system failure that caused hundreds of flight delays last week occurred because contractors “unintentionally deleted files” on the alert system for pilots, resulting in a standstill of planes and frustrated passengers.
The F.A.A. said in a statement that the employees had been attempting to “correct synchronization” between the essential database for the Notice to Air Missions alerts and a backup database when the files were mistakenly deleted, causing the outage that snarled air traffic throughout the day on Jan. 11.
Investigators have found no evidence of a cyberattack or other malicious intent, based on the agency.
“The F.A.A. made the needed repairs to the system and has taken steps to make the NOTAM system more resilient,” the agency said, referring to the Notice to Air Missions alerts.Those alerts are crucial to planning flights, based on the agency, and are used to share details about hazards within the air or on the bottom, equivalent to closed runways or airspace restrictions.
The error last Wednesday resulted in one more nationwide travel blunder for hundreds of passengers, just two weeks after mass cancellations by Southwest Airlines had left hundreds more stranded in December. Each episodes underscored the fragility of the country’s air travel system.
After the issue was discovered on Jan. 11, the F.A.A., just before 7:30 a.m., ordered airlines to delay all departing flights; the pause was lifted at about 9 a.m. But greater than 9,000 flights were delayed that day due to error. It was the newest example of problems within the aviation system and on the F.A.A., which is answerable for safely managing all industrial air traffic.
Critics of the agency say it has long been underfunded and that its employees are overworked, creating weaknesses that put travelers susceptible to severe delays at a time when air travel is roaring back from pandemic lows. The outage is prone to be highlighted in hearings and debates in Congress since the agency’s most up-to-date authorization expires this 12 months.