Boeing 747-400 United AirlinesUnited Airlines 747 400 airplane model. The revolutionary 747 had a huge impact on airline transportation. It surpassed all previous aircraft in size and significantly reduced operating costs per seat, making long haul international travel more affordable. Boeing originally conceived the 747 in the 1960s after failing to secure a contract with the US Air Force for a large strategic transport (which ultimately became the Lockheed C 5 Galaxy).