According to initial findings by the Federal Aviation Administration (FAA), the disruption in US air traffic is apparently due to a faulty database file. There is no evidence of a hacker attack, the FAA announced yesterday. However, the investigations are still ongoing. The faulty file affected not only the main system, but also the backup system, said people familiar with the investigations. Transport Minister Pete Buttigieg told CNN that after the failure of the NOTAM (Notice to Air Missions) system, which is important for flight preparation for pilots, the emergency system did start up. However, there were doubts as to whether it was working properly. A complete restart was therefore necessary, which prompted the FAA to halt all domestic flights for 90 minutes. So far, 9.600 flights have been delayed due to the disruption, and over 1.300 have been canceled, as the ORF reports. However, the number could still rise, as there are still disruptions. The airlines expect that air traffic should return to normal today. The impact on long-haul flights between the US and Europe was minor.