Inspect wire often, retired admiral says Kapton found in many jets By Gary Stoller Thur., Sept. 23, 1999 ALBUQUERQUE -- A type of electrical wire that runs throughout nearly half of all airline jets is prone to fail and should be regularly inspected, a former U.S. Navy admiral said Wednesday.  Polyimide wire, which is commonly known as Kapton, can degrade and lead to ''serious consequences,'' retired rear admiral Donald Eaton told wiring experts here at a government-sponsored conference on aging aircraft.  The wire type can cause violent arcing and a fire, he says, or cause electromagnetic interference or electronic noise.  An arc is an electrical current that jumps from an exposed conductor to another wire or a metal surface.  Eaton, who ordered Kapton removed from Navy planes in the 1980s, told USA TODAY that aircraft manufacturers should not continue to install polyimide wire on new jets.  ''The manufacturers need to seriously understand what they're doing and realize that there are better substitutes out there,'' he says.  Airlines should check problem-prone areas for wires that might need to be replaced and consider retiring their oldest jets equipped with polyimide wire, Eaton says. Polyimide is the dominant wire type on many Boeing 737s, 747s, 757s and 767s; MD-80s and MD-11s; and DC-10s. It is no longer used as the dominant wire on Boeing's newly built planes, but it is used for some systems.  Boeing officials did not comment on Eaton's remarks.  Polyimide wire also is on all Lockheed L-1011s and all Airbus jets. Airbus uses it in the pressurized areas of its new planes.  ''We believe polyimide is one of the best materials for the job because of low smoke emissions (when it fails) and low toxicity of those emissions,'' says Airbus spokeswoman Mary Anne Greczyn. ''We believe polyimide wiring is safe.''  Canadian investigators have found Kapton wires that arced during their probe into the cause of a fatal Swissair MD-11 crash near Nova Scotia last September. U.S. investigators found melted strands of another polyimide wire, Poly-X, in the wreckage of the TWA 747 jet that crashed near Long Island, N.Y., in 1996. But investigators have not determined that the polyimide wires  caused either crash.  Federal Aviation Administration officials say there is no reason for alarm.  ''We're dealing with aircraft in the commercial fleet, and they operate in different environmental conditions than military planes,'' says Beth Erickson, director of the FAA's aircraft certification office.