The JT8D is an axial-flow, dual-spool, medium bypass ratio, fully ducted turbofan. Its exact specifications depend upon the dash model. This course provides information regarding the purpose, description and operation of the various systems and sub-systems that comprise the Arrius JT8D engine. It includes Operating Limits and Abbreviations, Engine Operation, Engine Structure, General maintenance, Air Intake, Engine Fuel and Control, Ignition, Engine Air, Engine Controls (including propeller), Engine Indicating, Oil System, and Engine Rigging.