As 'fly-by-wire' technologies become more prevalent in the aerospace systems, the need to develop innovative monitoring, diagnostic and fault tolerant techniques for the electrical systems is becoming obvious. Among all the possible electrical system failures, two types of failures are considered the most frequent, and hence most critical: intermittent disconnection in connectors, and capacitance failures. Despite the extreme care in the design and quality control in manufacturing and installation of these connectors in avionics and military equipment, there are increasing number of problems associated with the physical connectivity that ranges from intermittent discontinuities, sparks, and breakages. As for the capacitors, the power systems in modem aircrafts, specifically the ones with DC power supply configurations, rely very heavily on banks of capacitors that act as filters. These capacitors (especially of electrolytic type) present high failure rates - with no effective solution for online monitoring available. The proposed research will study detecting fault initiation, fault-to-failure progression, and online monitoring of the critical problems of intermittent disconnection, and capacitance aging and ultimate failures in aircraft power systems. We propose to develop a non-traditional use of wideband differential current sensor to detect capacitor degradation, as well as intermittent disconnection problems. This program is expected to generate useful, accurate and precise diagnostic information impacting the safety and maintenance of critical aircraft power systems.