Reliability

Abstract

This paper describes the FT8 gas generator (008) development history, including required design modifications to the JT8D aircraft engine, initial field experience and the latest reliability improvements incorporated into the 008. The modifications include improvements to bearing compartment operating temperature, bearing compartment seals, and Increases to bearing life. Turbine durability improvements are also discussed. The incorporation and control of a cold air buffer system to control bearing compartment oil coke formation is provided. Improvements to bearing compartment carbon seals are reviewed and the benefits of this design are discussed. Rotor system thrust bearing life improvements are achieved through the incorporation of modified compressor seals and turbine aerodynamics.