gas turbine numerology
- All gas turbine engines, except those with bypass ducts, are given station designations from 0 to 9, with the station 0 denoting the area ahead of the inlet where the airflow is undisturbed and the number 9 denoting the exhaust flow conditions of the core engine at the nozzle exit. Stations 1 to 8 are the inlet diffuser, inlet duct, fan, compressor, burners, turbine, exhaust duct, and exhaust nozzle, respectively. When the engine has additional compressors or turbines, these are denoted by intermediate numbers like 4.5, 5.5, etc. Those engines with bypass ducts are designated in the same manner but have two numbers instead of one (i.e., the first number is 11). See engine station designation.
Aviation dictionary. 2014.