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Online security expert Chris Roberts joked on Twitter in mid-April that by hacking into a plane’s systems, he could get the oxygen masks to deploy. This earned him a greeting by the FBI after landing in Syracuse, N.Y., four hours of questioning, and seizure of his laptop and electronics.

A few days later, after being stopped from boarding a Colorado-to-San Francisco United flight, an airline spokesman confirmed it was due to the worrisome tweets. As reported by TravelPulse, via the AP, he added, "However, we are confident our flight control systems could not be accessed through techniques he described."

But court documents suggest the FBI does not agree, as per multiple reports. They appear to be building a case against Roberts for his airline hacking escapades.

Canadian news organization APTN acquired documents that contained transcriptions of interviews the FBI conducted with Roberts earlier this year. One part of an affidavit, signed by FBI agent Mike Hurley, says, "(Roberts) stated that he successfully commanded the system he had accessed to issue the 'CLB' or climb command. He 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."

According to the documents, Roberts hacked into the plane's controls via the in-flight entertainment system using a laptop, and an Ethernet cable. He claimed to the FBI that such entertainment system vulnerabilities exist in Boeing 737-800, 737-900 and 757-200 aircraft as well as Airbus A-320s.

Wired reported that Roberts told both them and the FBI that he has accessed "in-flight networks about 15 times during various flights but had not done anything beyond explore the networks and observe data traffic crossing them."

Roberts has repeatedly claimed publicly that he does not have malicious intentions.

Regarding airline safety from hacking, CBS News quoted a Government Accountability Office report that stated, "Modern aircraft are increasingly connected to the Internet. This interconnectedness can potentially provide unauthorized remote access to aircraft avionics systems."

Over last 5 years my only interest has been to improve aircraft security...given the current situation I've been advised against saying much

— Chris Roberts (@Sidragon1) May 17, 2015

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