The same people who are putting geese
out of the parka-insulation business have developed an electrical
insulation that may help keep aircraft on the wing a bit longer.
W.L. Gore & Associates, Inc., Newark, DE, makers of GORE-TEX
fabrics and a wide range of electronic, industrial and medical products,
has developed a high strength, flexible and abrasion-resistant fluoropolymer
insulation for aircraft wiring, which possesses important properties
critical to both electrical performance and safety.
In several highly publicized reports, consumer and safety advocates
have raised concerns about the performance of current insulation
systems for wiring in aircraft. Current aircraft wiring involves
the use of crosslinked ETFE (such as TEFZEL), polyimide (such as
KAPTON), or a composite insulation system of PTFE/Polyimide over
the conductor. The crosslinked ETFE exhibits poor performance at
elevated temperatures and produces smoke. The composite insulation
system was developed to address the electrically conductive carbon
char that develops when the polyimide is subjected to a high voltage
arc. However, the composite has an outer layer of PTFE that exhibits
poor cut-through, creep and abrasion characteristics.
The High Strength Toughened Fluoropolymer (HSTF) does not exhibit
creep and cut-through properties typically associated with PTFE
insulation. The Gore fluoropolymer insulation also does not form
an electrically conductive carbon char when subjected to an arc,
as occurs with polyimide insulation. Gore HSTF insulated wire can
be used in all parts of the aircraft, from fuel probe cables to
general purpose hook-up wires, due to the wide temperature performance
(260°) and chemical inertness of the material.
Gore is currently engaged in programs with several aircraft manufacturers
(both military and commercial), airlines and aircraft component
suppliers regarding testing and potential utilization of HSTF insulated
For more information, contact
W.L. Gore & Associates, Inc., 555 Papermill Rd, Newark,
DE 19714. 302-738-7880.