Projectile Impact Effects on Aircraft Wire Harnesses
Abstract
Naval aircraft wiring harnesses, representative of the construction of one carrying the power and signal circuits of an F-14 harness were shot at under controlled conditions to observe the effects produced by the impacts of hostile projectiles. The results of these tests, conducted in the NRL Ballistics Facility, have demonstrated that the effect can be serious and that the combustive reactions from the electrical arcing resulting from the shearing damage of the impact will be more severe for some types of wire insulation than for another. This experiment provided a direct comparison between wiring insulated with an aromatic polyimide insulation system and a radiation crosslinked ethylene tetrafluoroethylene (modified ETFE) insulation. Despite the fact that the same electrical power was applied to both types, the harnesses of the aromatic polyimide wires ignited and burned, whereas the other did not. From the way the fire propagated along the harnesses, tripping more circuit breakers as additional wires were engulfed in flames, it was apparent that the aromatic polyimide forms a carbonaceous char that is conductive. The reaction then causes the short circuiting to progress along the harness as long as there is a voltage potential between adjacent wires. Keywords: Electrical insulation; Aircraft wire harnesses; Aromatic polyimide; Modified ETFE; Short circuits; and Projectile damage and fires.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 08, 1986
- Accession Number
- ADB098840
Entities
People
- C. J. Skowronek
- F. J. Campbell
Organizations
- United States Naval Research Laboratory