The US air traffic control system is vulnerable to hackers, according to the US Government Accountability Office.
In an update to an investigation first carried out in 2000, the agency said the Federal Aviation Administration (FAA), which runs the system, had made some progress in protecting systems but that they remained vulnerable.
Shortcomings include outdated security plans, inadequate staff awareness training, and doubts about whether the FAA can detect network intruders and keep the system running during a security breach.
In its report the agency said that the FAA had “not adequately managed its networks, software updates, user accounts and passwords and user privileges”.
The US air traffic control system handles around 46 million flights a year.