At some point or another, everyone experiences a jerk on a plane. Whether they're verbally or physically disruptive, unruly passengers are out there, and they're causing airlines to take certain (read: badass) precautions.
Russia's Pobeda Airlines has said that they're going to teach their crew martial arts so that flight attendants can protect themselves and other passengers. The move comes after an incident where a passenger started swinging violently at an employee after he missed his flight, and it wasn't even the first time. Hong Kong Airlines has had similar experiences, and has since trained their crew in kung fu.
According to a recent article by Quartz, "The International Air Transport Association says that 1,194 of the close to 11,000 reported incidents of unruly passengers in 2015 involved physical aggression against crew or fellow travelers."
Since safety in the air is a flight attendants top priority, the move makes sense. We're just waiting for someone to pick it up for a fight club parody. Or should we say, flight club.