Fulfilling the Army's need for engines of simple design that are easy to operate and maintain, the gas turbine engine is used in all helicopters of Active Army and Reserve Components, and most of the fixedwing aircraft to include the Light Air Cushioned Vehicle (LACV). We designed this subcourse to teach you theory and principles of the gas turbine engine and some of the basic army aircraft gas turbine engines used in our aircraft today. There are no prerequisites for this subcourse. This subcourse reflects the doctrine which was current at the time it was prepared. In your own work situation, always refer to the latest publications.