ATE for older systems-an engineer´s perspective

Many line replaceable units (LRUs) and shop replaceable units (SRUs) still successfully flying in the US Air Force employ earlier analog technologies. These aging units are often tested on older generation automatic test equipment (ATE). As these LRUs and SRUs approach the end of their useful lives, their increased failure rates often require additional ATE resource time from what may be already overburdened test sets. The author discusses the impact of existing LRU/SRU hardware design on test strategy and the additional constraints imposed by the ATE chosen to perform the required tests. He also addresses some of the issues in ATE software design, such as single- or multiple-fault testing, and what, from an engineer´s perspective, should compromise good test program sets and test requirement documents