The FBI says that security expert Chris Roberts admitted to hacking into a plane’s controls and making the aircraft fly sideways.

Roberts also told the FBI that he had hacked into planes’ in-flight entertainment systems 15-20 times.

Experts: Hackers Could Bring Down Planes Via In-Flight Entertainment System reported:

Roberts reportedly told the agents that he was able to overwrite the code for the thrust management computer. When he ordered the hacked engine to climb, the plane moved sideways as it flew.

The document, which was first reported on by the Canadian news service APTN, also claims Roberts was able to monitor air traffic using the cockpit's own system.

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“Cyber Guy” Kurt Knutsson addressed Roberts' claims that he can deploy oxygen masks, increase the engine thrust, change the aircraft’s course, move fuel between onboard tanks and make the nose of the plane go up.

“Those are really serious control issues that no passenger should have access to in an aircraft, and so we have got to do something,” Knutsson said.

Last month, Roberts wasn’t allowed on a United flight after he tweeted that he could deploy the plane’s oxygen masks.