Chris Roberts, founder of Denver-based cybersecurity firm One World Labs, said he was banned from getting on a United Airlines flight last week because of a Tweet he posted. Roberts was on his way to the RSA security conference to talk about computer security vulnerabilities. He’s also a keynote speaker at the SCTE Cable-Tec Expo’s Cybersecurity Pre-conference Symposium on Oct 13 in New Orleans. While waiting for his flight, Roberts posted a tweet about whether he would be able to hack into the flight’s computer system, USA Today reported. “Find myself on a 737/800, lets see Box-IFE-ICE-SATCOM,? Shall we start playing with EICAS messages? “PASS OXYGEN ON” Anyone?:)” his tweet read. United Airlines reportedly reached out to Roberts and basically told him he wouldn’t be allowed to board his plane. Roberts was able to get on another flight from another airline, the paper said.