I think you’re referencing https://en.wikipedia.org/wiki/United_Airlines_Flight_585 https://en.wikipedia.org/wiki/United_Airlines_Flight_585 “The National Tra

I think you’re referencing https://en.wikipedia.org/wiki/United_Airlines_Flight_585 https://en.wikipedia.org/wiki/United_Airlines_Flight_585 “The National Transportation Safety Board determines that the probable cause of the United Airlines flight 585 accident was a loss of control of the airplane resulting from the movement of the rudder surface to its blowdown limit. The rudder surface most likely deflected in a direction opposite to that commanded by the pilots as a result of a jam of the main rudder power control unit servo valve secondary slide to the servo valve housing offset from its neutral position and overtravel of the primary slide”