We have completed two-thirds of our journey through sustainability engineering for systems engineers, and our final push is through the landscape of supportability engineering. While we strive to avoid failures through design for reliability, failures are nonetheless inevitable at least because it is at least possible, if not indeed likely, that we may not be able to anticipate all the possible failure modes in a system. So a well-designed system, anticipating that outages will occur, incorporates features that help minimize their duration. In the extract from a system history diagram shown in Figure 10.1, the outage period is divided into two parts: an initial period of time devoted to preparation for repair and a subsequent period of time devoted to execution of repair. This distinction is made so that each duration may be minimized separately by the application of techniques particular to the needs of the two activities of preparation and execution. Maintainability engineering, the body of knowledge connected with execution of repairs, was the subject of Part II of this book. We now turn to supportability engineering, the body of knowledge connected with preparation for repair, in Part III.
This chapter begins the study of supportability engineering by examining support requirements. To do this, we need to know