ABSTRACT
M AINTAINABILITY engineering is an engineering discipline that for mulates a satisfactory combination of design features, maintenance fa
cilities, and repair policies to acquire a given level of maintainability, as an op erational requirement, at minimum life cycle costs. In contrast, maintainability is a design characteristic that, when effectively achieved, contributes to fast, ef ficient, and straightforward maintenance at the minimum life cycle cost. Since the term maintenance is often incorrectly interchanged with maintainability, the clarification of their true meanings is absolutely essential. Maintainability is design-related and, thus, considered during the design of a product; in con trast, maintenance is operation-related and refers to those activities performed after the product is functioning in the field to keep it in operational condition or to repair it to an operational state after experiencing a failure.
