Fuel Cost (per Seat per NM). Compared to the average Turbofan-powered Narrow-body Commercial Passenger Plane, which costs $12.68* per nautical mile and 11.35Â¢* per seat per nautical mile to operate, the Boeing 737-900ER is:1  $2.02 more expensive per nautical mile (a 16% premium).2  3.05Â¢ cheaper per seat per nautical mile (a 27% margin).uel Cost (per Seat per NM). Compared to the average Turbofan-powered Narrow-body Commercial Passenger Plane, which costs $12.68* per nautical mile and 11.35Â¢* per seat per nautical mile to operate, the Boeing 737-900ER is: