Abstract: The diagnostic system makes use of a knowledge based controller and a plurality of data logger units, at least one of which is a wireless unit, to collect temporally coordinated data indicative of the real time operation of a system under test that comprises a plurality of spatially disjunct but operationally interdependent components. The diagnostic system controller automatically architects an instrumentation plan to collect the data and calculates performance factors from this collected data. A comparison of the calculated performance factors with optimum and typical failure mode performance factors identifies performance problems in the system under test.