Powerplant maintenance practices are undergoing major changes from the early days of time-controlled overhauls of the complete jet engine. Through utilization of a program of investigation of premature removals of engines, trouble spots were pin-pointed, modifications developed, and the practice of sample overhauls of engines was completely eliminated.
Another proposal being developed is the concept of “threshold” sampling whereby an initial sampling age is specified rather than progressive ages at which samples must be taken.
With the next generation of aircraft, new practices in maintenance must be undertaken such as pooling of engines and components for maintenance purposes between operators, decentralization of the maintenance function, accessibility for inspection of the engine, as well as condition-monitoring of engine components.
In conclusion, a close liaison must be maintained between manufacturer and the airlines on the engineering level so that the designer is kept aware of production design criteria under actual operating conditions.