Safety expert: 

Aircraft wiring a 'time bomb' Conference calls for circuit breakers that detect deadly faults
By Gary Stoller
Wed., Sept. 22, 1999
FINAL EDITION
Section: MONEY
Page 2B


ALBUQUERQUE -- Malfunctioning electrical wires on aging airliners are a
''time bomb'' that the industry must try to defuse, a safety expert for
the nation's largest pilots union said Tuesday.

Intermittent short circuits in airplane wiring -- known as ticking
faults -- have caused accidents, says Ken Adams, Air Safety Committee chairman of
the Air Line Pilots Association, at a government-sponsored conference here on
aging aircraft.

Ticking faults, which can result from damaged wire insulation, often go
undetected until a fire or another major problem occurs.

They can cause a wire to arc, sending an electrical current in excess of
1,000 degrees Fahrenheit from an exposed conductor to another wire or a
metal surface.

''Most pilots believe circuit breakers will protect them, but existing
circuit breakers don't detect arcing faults,'' says Adams, a Delta Air
Lines MD-11 pilot.

What is needed, several wiring experts at the conference say, are circuit
breakers that can detect arcing. Technology also is needed to help pilots
identify the location of wire problems when they occur, Adams says.

Accidents involving ticking faults or arcing include a fatal fire aboard
the Apollo One spacecraft in 1967 and a fatal fuel tank explosion of a
Philippine Airways Boeing 737 in 1990, he says. An electrical malfunction, Adams
says, also may have caused TWA Flight 800 to explode off the coast of Long
Island, N.Y., in July 1996, killing all 230 people aboard.

The National Transportation Safety Board is investigating wiring as a
possible cause of the explosion but is considering other possibilities,
too, investigator Robert Swaim says.

Adams says that a wiring malfunction was the likely cause of the deaths of
all 229 people aboard a Swissair MD-11 jet that crashed near Nova Scotia
last September. He is part of an international contingent of pilots that has
examined the wreckage and observed the Canadian government's accident
investigation.

''All indications are that it was probably an arcing event, but the
investigators don't have conclusive proof,'' Adams says.