Accidental File Deletion Led to NOTAM Crash, FAA Says

The contract personnel’s mistake made while synchronizing databases affected an estimated 4,000 flights.

All domestic flights in the U.S. were grounded early January 11 after the FAA’s online Notices to Air Missions (NOTAM) safety briefing system crashed. [Credit: Shutterstock]

Last week's safety notice system meltdown that spurred a nationwide ground stop and thousands of delayed and canceled flights was caused by a contract worker accidentally deleting files, according to the Federal Aviation Administration (FAA).

The FAA also reiterated that their preliminary investigation into the notice to air missions (NOTAM) system crash did not uncover evidence of a cyber-attack or "malicious intent."

"Contract personnel unintentionally deleted files while working to correct synchronization between the live primary database and a backup database," FAA said in a statement Thursday.

According to the agency, the necessary repairs have been made to the system, and they are still investigating the circumstances surrounding the outage. The FAA noted the agency has taken steps to make the NOTAM system more resilient, and is using the experience as a teaching tool.

System Meltdown

Early January 11, airline travelers found their morning flights canceled or significantly delayed after the FAA uncovered that a failure in the NOTAM system had occurred overnight.

NOTAMs provide essential information to pilots about the abnormal status of a component of the national airspace system, such as ground-based navigational system failures at airports, GPS outages, and facility closures. Pilots are required to check for NOTAMs pertinent to their departure airport, route, and destination as part of preflight planning.

The FAA ordered airlines to pause all domestic departures until 9 a.m. eastern time "to allow the agency to validate the integrity of flight and safety information.” The agency continued to provide updates throughout the day as they worked to mitigate the situation.

According to, more than 4,000 flights were impacted by the outage as more flights were canceled or delayed and rescheduled.

Meg Godlewski has been an aviation journalist for more than 24 years and a CFI for more than 20 years. If she is not flying or teaching aviation, she is writing about it. Meg is a founding member of the Pilot Proficiency Center at EAA AirVenture and excels at the application of simulation technology to flatten the learning curve. Follow Meg on Twitter @2Lewski.

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