The purpose of this paper is to describe and illustrate how designing for maintainability in modern ultra high bypass ratio turbofan jet engines has significant cost advantages for both the airline operator and the engine manufacturer. It is also necessary to include in the process of designing for maintainability innovations which optimize the airline's ability to utilize engine assets in the most cost effective manner.
Contemporary jet engine design evolved to the degree that major engine functional units could be disassembled without disturbing adjacent units to facilitate maintenance in the engine shop, the familiar modular maintenance concept. This was innovative when developed in the early 1970's but today's 80,000 pound thrust class engines require new initiatives.
The significance of designing for maintainability lies in the changing technical atitudes which now recognize that a specific and disciplined process needs to be put in place to acknowledge and understand the “previous design process” short comings relative to reliability impact either directly or indirectly caused by poor or negligent maintainability ergonomics.
All of the above factors led to organizing a methodical approach based on previous experience of the CF6 and CFM56 engines regarding the design development of the all new GE90 ultra high bypass ratio turbofan engine.