Jeff Smisek, chief executive of United Airlines, denied claims by Chris Robert claims he has hacked several aircraft, which was revealed in court documents in the US. Smisek told a US Senate hearing that there are “clear firewalls between a Wi-Fi system and any kind of control". He did however state that any possibility of contagion was a supreme concern and that United was cooperating with a Federal Bureau of Investigation (FBI) probe into the matter. Smisek told the Senate panel of the alleged hacking, reported on this news service yesterday, that "We are unaware of whether or not this is possible (but) the original equipment manufacturers, from at least what I understand, have stated this is not possible today.