When should you consider adopting an aircraft wire life extension program? Part IV

Subtopic: Applying Technology to your Fleet – Step #1

For purposes of aircraft wire life extension, start with identifying what wires are on the aircraft (see Lectromec’s When should you consider adopting a wire life extension program? Part III article article). It is then necessary to perform a selective sampling of the aircraft. Obviously, the harshest environment for aircraft wires is during the time the aircraft is in operation. These stresses do build up over time and add to the degradation that occurs to the wire insulation during its time on the ground.

The first step is to gather information on the physical conditions within the aircraft. The environment examination, broken down into individual zones, considers the severity of environmental conditions. This is done because the environmental conditions provide good information about the types of stress that impact wire longevity. The successful determination of the environmental condition an aircraft has been exposed to provides details for the forecasting of failure areas.  As can be seen in the photo below, there are a number of maintenance zones even for a small aircraft.

The examination of the types of environmental conditions an aircraft is exposed to starts with partitioning of the aircraft into environmental zones. The environmental zones are defined as contiguous physical areas on the aircraft that have similar environmental characteristics. Examples of particular environmental characteristics include, but are not limited to:

• Operating temperature
• Vibration level
• Exposure to fluids

While physical examination and monitoring of the aircraft is ideal, it is not practical in all cases. As such, it is often necessary to survey a small group of individuals (engineers and technicians) familiar with the aircraft. This survey covers each aircraft zone and elicits opinions on the environmental conditions. The results from this survey are evaluated and similar contiguous environmental zones are grouped together.