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This paper reviews the characteristics of a power line network as data communication medium and studies the challenges encountered when communicating over power wiring. This technology review has been done as part of feasibility study for using aircraft power-lines for data communication. Power-Line Communication is a term which describes the use of existing electrical lines to provide the medium for a high speed communications network. Power Line Communications is achieved by superimposing the voice or data signals onto the line carrier signal using an appropriate communication technology. Power Line Communications represent a potential simplicity for communications among different devices, because it does not need additional wires for connecting devices network together. Power line cables have been used as a communication medium for many years. However, because power line cables are not designed for communication, they pose major challenges for a modem designer.

With the prevalence of more electrical aircraft (MEA), aircrafts are more vulnerable to electrical system faults. The proactive Condition Based Maintenance (CBM) for aircraft electrical systems has become an issue of substantial importance and urgency. Although certain aspects of CBM have been implemented with considerable success, CBM for aircraft electrical systems is still at its early stage of development. Diagnostic and prognostic technologies need to be improved to meet CBM requirements. This paper reviews the existing studies on the CBM for aircraft electrical systems in terms of its concept, content, requirements, hierarchy, methodologies and system configuration, and is intended to provide a technology survey particularly on the state of the art and challenging issues of aircraft electrical system CBM.

Power Line Communication (PLC) is considered one of emerging technologies for the Next Generation Aircraft. Power lines can be used as an internal data exchange media within aircraft subsystems, such as the Electric Power Distribution System (EPDS). PLC is a term which describes the use of existing electrical power lines to provide the medium for a high data speed networks to replace extra cables, thereby reducing the installation cost and net weight in aircraft wiring. This paper reviews different multiple access techniques and advantages/disadvantages of each technique using power line networks as a data communication medium. Power line channels include various types of noise and interference hence there are major challenges when communicating over power lines. A designer must consider the limitations in the power line communication channels such as propagation factor, impedance mismatch, noise and electromagnetic compatibility.

This paper provides an overview of recent developments in the area of arc fault detection (AFD) and wire fault location for aircraft wiring systems. Arc faults have been identified as one of the greatest threats to human lives and properties, and the likely cause of several aircraft disasters. With the introduction of high voltage transmission in aircraft to reduce the wiring weight and to meet the increasing power demands, the probability of initiating and sustaining continuous arcs in modern aircraft have been increased. However, arc faults are hard to detect and wiring problems are difficult to locate in aircraft, due to their complex profiles, high impedance property, and pressure sensitive characteristic, etc. The difficulty in resolving this problem is also due to the fact that false alarms cannot be tolerated but missing alarms can be fatal, and arc faults are normally intermittent as a result of the in-flight vibration.

There is a growing need for high voltage direct current (HVDC) power distribution systems in aircraft which provide low-loss distribution with low weight. Challenges associated with HVDC distribution systems include improving reliability and reducing the size and weight of key components such as electric load control units (ELCUs), or remote power controllers (RPCs) for load control and feeder protection, and primary bus switching contactors. The traditional electromechanical current interrupting devices suffer from poor reliability due to arcs generated during repeated closing and opening operations, and are generally slow in isolating a fault with potentially high let-through energy, which directly impacts system safety.