Arc tracking. A phenomenon in which a conductive carbon path is formed across an insulating surface. This carbon path provides a short circuit path through which current can flow. Normally a result of electrical arcing. Also referred to as "Carbon Arc Tracking," "Wet Arc Tracking," or "Dry Arc Tracking."
Combustible. For the purposes of this TP the term combustible refers to the ability of any solid, liquid or gaseous material to cause a fire to be sustained after removal of the ignition source. The term is used in place of inflammable/flammable. It should not be interpreted as identifying material that will burn when subjected to a continuous source of heat as occurs when a fire develops.
Contamination. For the purposes of this TP, wiring contamination refers to either of the following:
- The presence of a foreign material that is likely to cause degradation of wiring.
- The presence of a foreign material that is capable of sustaining combustion after removal of ignition source.
Detailed Inspection (DET). An intensive examination of a specific item, installation, or assembly to detect damage, failure or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses or other means may be necessary. Surface cleaning and elaborate access procedures may be required.
Electrical Wire Interconnection System (EWIS). An electrical connection between two or more points including the associated termination devices (e.g., connectors, terminal blocks, splices) and the necessary means for its installation and identification. (See Appendix D, Electrical Wire Interconnection System.)
Functional Failure. Failure of an item to perform its intended function within specified limits.
General Visual Inspection (GVI). A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight or droplight and may require removal or opening of access panels or doors. Stands, ladders or platforms may be required to gain proximity to the area being checked.
Lightning/High Intensity Radiated Field (L/HIRF) protection. The protection of aircraft electrical systems and structure from induced voltages or currents by means of shielded wires, raceways, bonding jumpers, connectors, composite fairings with conductive mesh, static dischargers, and the inherent conductivity of the structure; may include aircraft specific devices, e.g., RF Gaskets.
Maintenance. As defined in CAR 101 means the overhaul, repair, required inspection or modification of an aeronautical product, or the removal of a component from or its installation on an aeronautical product, but does not include:
- elementary work,
- servicing; or
- any work performed on an aircraft by the manufacturer prior to the issuance of the first certificate of airworthiness or the export airworthiness certificate;
However, due to collateral wiring damage that frequently occurs when work is performed on aircraft, TCCA for the purposes of this TP document, interprets "Maintenance" to include those activities that are defined as (a) elementary work, (b) servicing, and (c) any work performed on an aircraft by the manufacturer prior to the issuance of the first certificate of airworthiness or the export airworthiness certificate.
Maintenance Significant Item (MSI). Items identified by the manufacturer whose failure could result in one or more of the following:
A. could affect safety (on ground or in flight).
B. is undetectable during operations.
C. could have significant operational impact.
D. could have significant economic impact.
Needling. The puncturing of a wire's insulation to make contact with the core to test the continuity and presence of voltage in the wire segment.
Stand-alone GVI. A General Visual Inspection which is not performed as part of a zonal inspection. Even in cases where the interval coincides with the zonal inspection, the Stand-alone GVI shall remain an independent step within the work card.
Structural Significant Item (SSI). Any detail, element or assembly that contributes significantly to carrying flight, ground, pressure, or control loads and whose failure could affect the structural integrity necessary for the safety of the aircraft.
Swarf. A term used to describe the metal particles, generated from drilling and machining operations. Such particles may accumulate on and between wires within a wire bundle.
Zonal Inspection. A collective term comprising selected General Visual Inspections and visual checks that are applied to each zone, defined by access and area, to check system and power plant installations and structure for security and general condition.