Evaluation of wiring constructions for space applications

A NASA Office of Safety and Mission Assurance (OS&MA) program to develop lightweight, reliable, and safe wiring insulations for aerospace applications is being performed by the NASA Lewis Research Center (LeRC). As part of this effort, a new wiring construction utilizing high strength PTFE (Poly Tetrafluoroethylene) as the insulation has been tested and compared with the existing military standard polyimide-based MIL-W-81381 wire construction. Electrical properties which were investigated included ac corona inception and extinction voltages (sea level and 60.000 feet), time/current to smoke, and wire fusing time. The two constructions were also characterized in terms of their mechanical properties of flexural strength, abrasion resistance (23/spl deg/C and 150/spl deg/C), and dynamic cut-through (23/spl deg/C to 200/spl deg/C). The results obtained in this testing effort are presented and discussed in this paper.<>