For the great majority of endeavours, aviation is the domain of symmetry and streamlining, while weight and drag are the constant enemies of efficient flight. The process of carrying a fifth engine on the Boeing 747 puts these norms to the test while turning heads and creating conversation, as Owen Zupp explains
As long as airliners have been powered by jet engines, a common design has been the mounting of the powerplant on the wing. Connected to the airframe by pylons, the turbofan is encased in a cylindrical cowling designed to house components, maximise engine performance and minimise any resistance to the airflow. This arrangement is sometimes referred to as a ‘pod’.