Design Features for Maintainability in the Pratt and Whitney Aircraft J9D Gas Turbine Engine

The Pratt & Whitney Aircraft 43,500 lb thrust turbofan engine will power the Boeing 747 large commercial transport airplane. The JT9D engine is a two-spool, high bypass ratio engine with outstanding performance, high thrust to weight, and low noise levels.

This advanced technology gas turbine engine represents a major step in improved maintainability through the use of simplified structural design and unit component construction which will substantially reduce assembly and disassembly time and, in turn, facilitate on-the-wing maintenance. Provisions for borescope or radioisotope inspection, along with improved monitoring of engine parameters, will facilitate installed engine condition monitoring.