A security researcher hijacked an airplane's engines after hacking its in-flight entertainment systems, according to the US Federal Bureau of Investigation.

Chris Roberts, a well-known US security researcher, told FBI agents in February that he'd hacked in-flight entertainment systems on over a dozen flights and on one occasion hijacked an aircraft's thrust management computer and briefly altered its course.

Security researcher, Chris Roberts, told FBI agents that he'd hijacked an aircraft's thrust management computer and briefly altered its course. Credit:Fox News

"[Roberts] stated that he thereby caused one of the airplane engines to climb resulting in a lateral or sideways movement of the plane during one of these flights," FBI agent Mark Hurley wrote in a warrant application filed in April and obtained by technology publication Wired on Friday.

The FBI seized Roberts' computers and questioned him after he was escorted off a United Airlines flight last month, because he'd posted a tweet — apparently in jest — hinting he could tap into the aircraft's crew alert system and cause passenger oxygen masks to drop.