C-17 portable advanced diagnostic system

The issue of Can Not Duplicate and Re-Test OK (CND/RTOK) for aircraft systems is one that has troubled the USAF for many years. This problem is being exacerbated by the increasing complexity of military avionics systems. The impact of these unnecessary line replaceable unit (LRU) removals is an increased burden on the USAF supply and maintenance system. Boeing Airlift and Tanker Programs is developing the Portable Advanced Diagnostics System (PADS) to both reduce CND/RTOK on the fielded C-17 A aircraft and aid in production integration and test. PADS is a software application that performs the following functions: 1) augments the aircraft on-board fault isolation capability to preclude the unnecessary removal of good LRUs; 2) correlates LRU reported faults, crew and maintainer observations, and aircraft fault history to disposition faults that can not be duplicated. The results of PADS implementation will be: (1) improved mission effectiveness; (2) reduced life cycle cost and maintenance man-hours per flight hour; (3) decreased aircraft turnaround time; and (4) decreased production costs.