TABLE OF CONTENTS The goal of the maintainability program is to improve the operational availability of system while reducing the requirements for personnel and other logistics resources. The methods used by maintainability engineers to achieve this goal are similar in methodology to reliability engineering. The methodology consists of a series of analyses and then testing and assessment, as shown in Figure 5-22.
Maintainability modeling
Maintainability allocations
Maintainability predictions
Failure modes, effects, and criticality analysis
Design criteria
Maintainability/supportability demonstration
Data collection, analysis, and corrective action system
The use of models for determining the maintainability of a system forms the basis for having the ability to predict the ease with which maintenance will be performed on the system. They should be developed early in the concept phase. Through use of an appropriate model, maintainability engineers can develop an initial prediction of system maintainability and subsequently determine the effect of changes on the total system and evaluate the need for redesign to achieve maintainability goals. The selection or tailoring of the appropriate model to be used to determine the maintainability characteristics of a system is the first step in predicting the number of hours that the system will be unavailable for use. The models that are provided in the handbook must be tailored to reflect the appropriate configuration and complexity of the system.
Figure 5-23 illustrates the model used to predict the MTTR of an item. The model for MTTR prediction uses the common tasks required...
