\n<\/p>\n

(NewsNation<\/a>) \u2014 The Federal Aviation Administration announced Thursday that a preliminary review found that contract personnel “unintentionally deleted files” disrupting a key computer system and prompting a nationwide ground stop on Jan. 11<\/a> that disrupted more than 11,000 flights.<\/p>\n

The\u00a0FAA\u00a0said the issue occurred while personnel were working<\/a> “to correct synchronization between the live primary database and a backup database.” The\u00a0FAA\u00a0said\u00a0it “has so far found no evidence of a cyber-attack or malicious intent.”<\/p>\n

Billy Nolen, the FAA\u00a0acting administrator, plans to hold a virtual briefing Friday for lawmakers and staff, who have sought details of what went wrong with a pilot messaging database that led to the first nationwide grounding of departing flights since the Sept. 11, 2001, attacks.<\/p>\n

Last week, the agency said the computer outage of the Notice to Air Missions (NOTAM) messaging system<\/a> was caused by a procedural error related to a corrupted data file. The NOTAM system provides pilots, flight crews and other users of U.S. airspace with critical safety notices.<\/p>\n