Here is another conspiracy theory about Flight 800:
>>Aviation detective story: Experts track the spark of potential killer
The News Tribune; Sean Griffin (Now employed by Boeing to do PR Work!)
The article follows: Aviation detective story: Experts track the spark of potential killer:
Warnings about explosive electrical arcs in aircraft wiring finally get hearing. During 10 years as the Pentagon's top expert on
aircraft wire, Ed Block became convinced that bad wiring insulation in everything from a Boeing 747 to an F-14 fighter was a
bomb waiting to go off. Nobody bought it.
But now the aviation world - stung by the explosion last July of TWA Flight 800 and the fire that brought down ValuJet Flight
592 two months earlier - is hungry for answers. There is heightened concern that wiring may have played a role in those
unexplained crashes. And today, Ed Block gets a long-awaited chance to make his case. His congressman, Rep. James
Greenwood (R-Pa.), summoned representatives of the Federal Aviation Administration, National Transportation Safety Board,
Federal Bureau of Investigation, a number of congressional committees and others to hear Block at a closed-door meeting.
Block contends that there is an inherent defect in a number of wires made by Raychem Corp., including one called Poly-X.
Poly-X insulated wire was the type used in TWA 800 and a few hundred 747s built in the early 1970s.
The investigation centers on a mystery: What prompted the vapors in the nearly empty auxiliary fuel tank on TWA 800 to
explode? Two emergency orders from the FAA raise the possibility that the whistle blower may be, if not precisely on target, at
least close to the mark. The FAA on Jan. 3 ordered a onetime inspection to detect "damage of the sleeving and wire bundles" of
the fuel boost pump on the auxiliary and outboard fuel tanks of 747s. The FAA acted after determining that "an environment
conducive to vibration exists in the conduit and wire bundles ... which cause(s) abrasion of the Teflon sleeving and subsequent
abrasion of the wires in the bundles . . . which could result in electrical arcing between the wires and the aluminum conduit and
subsequent fire or explosion of the fuel tank." An earlier order, issued Aug. 16, requires ongoing inspections of wire insulation,
electrical connectors and wire terminal assembly on the fuel pump. Corrosion, the FAA said, could cause arcing that could lead
to a fuel leak and fire.
Block, who lives in Bucks, Pa., calls himself "the poster boy of Retaliation 101." Once highly commended for his work -
including a nomination for Most Outstanding Person by the Defense Logistics Agency - Block was drummed out of the Defense
Department on a charge of falsifying a $43 travel expense. Block says the charge was invented to silence his whistle-blowing.
Tracking insulation defects:
Block's alter ego is Patrick Price. The Federal Way resident retired five years ago from Boeing, where he worked as a
technician at the Wire and Cable Arc Resistance Test facility in Seattle. Block believes there is an inherent defect in a number of
wire insulation types built by Raychem Corp.; Price is worried equally about one of DuPont's products - a wire insulator called
Kapton. Airplane manufacturers like Kapton because it is lightweight and strong. But when it is subjected to high temperatures -
such as when a wire is arcing - the insulation itself chars. Because carbon conducts electricity, the charred insulation helps
propagate an arc-tracking event or flash over, generating temperatures of as much as 2,000 degrees Fahrenheit. Price says his
six years of testing different wire types alarmed him so much that he won't let his children and grandchildren fly on any plane
built before 1992 - and only two models built since then. "If it's not a 737 or 757 built after 1992, they don't fly," Price said.
Price helped Boeing develop a new wire insulation, BMS 13-60. It also contains Kapton, but it's sandwiched between layers of
Teflon to make it safer. Price said Boeing was unable to make it produce an explosive arc-tracking flash over.
Kapton has been in use for nearly 30 years, first making its appearance in commercial aviation in 1972 with the Lockheed
L-1011 and the McDonnell Douglas DC-10. Within a few years of its introduction, problems became apparent - especially on
carrier-based Navy planes, whose wire bundles frequently were contaminated with moisture from saltwater, mist, fog and high
humidity. The stiffness of Kapton wires made it difficult to route wire bundles through a carrier plane's tight channels and around
corners. And when a crack developed in a Kapton-insulated wire at sharp bends, a radial crack developed all the way through
to the metal conductor. When the power is turned on, according to a 1984 report from the Naval Research Laboratory,
electrical arcs jump from the bare wire to the surfaces of the wet bundles, creating dry spots that char and become additional
paths for arcing. "Each time the aircraft descends from the extreme cold of a high-altitude mission into the high humidity of the
carrier deck, the condensation on contaminated wires repeats the cycle . . . until failure strikes," wrote F.J. Campbell, who
authored the Naval Research Laboratory report.
First commercial problems noticed:
Those kinds of conditions weren't typical in the commercial aviation world. And fires or failures related to the use of Kapton
insulation hadn't ever happened in flight on commercial jetliners, as they had on Navy jets. At least they hadn't until a month after
the Navy report, when an electrical fire erupted aboard a Monarch Airlines flight between the Canary Islands and England. The
plane was 3,000 feet above the Atlantic when passengers and crew heard two loud pops and watched in alarm as the cabin
filled with smoke. The circuit breakers above the flight crew tripped, and a strange thing happened: When the captain reset the
circuit breakers, the smoke got worse. The plane lost all main electrical power. Yet, because all commercial aircraft have
backup systems, the plane landed safely in Portugal. The problem occurred when fluid (urine) from a leaking toilet dripped onto
a defective wire bundle (damaged insulation). But the analysis was cause for alarm. "Something had happened where our
insulation had broken down. We didn't understand it and started to look into it," said Alex Taylor, who led the team that set up
Boeing's wire test lab and created the new BMS 13-60 wire.
A similar phenomenon had been seen on another plane, a United Airlines Boeing 767, where an arc-tracking event damaged a
number of wire bundles. To date, Taylor said, those are the only two major incidents in Boeing's fleet that can be traced to arc
tracking, though finding burned wires during maintenance checks is not unusual.
(This NOT a true statement. A 737-300 had a fuel tank blow up in Manila due to arc-tracking).
Other manufacturers have had episodes of arcing. In 1983 an SAS MD-80 erupted in smoke and flames on touchdown after
two wires pinching together arced to the fuselage. The arcing was so intense it melted a one-foot diameter hole in the fuselage,
yet no circuit breakers tripped. Two years earlier, a Delta Airlines L-1011 made an emergency landing after a cabin wall
erupted in flames. The ignition source was undetermined, but some of the wires in a bundle next to the fire showed signs of
arcing. "When you can melt a one-foot hole diameter in airplane skin and it doesn't trip the circuit breakers, you know
something's rotten in Denmark," Price said. In the mid-1980s, the Navy banned the further use of Kapton - even for repairs.
Looking for solutions:
What bothers Price is that millions of feet of Kapton-insulated wiring remain on aircraft around the world. He believes a tragedy
is unavoidable - and already may have occurred. It would be nice, he says, if all aircraft with Kapton-insulated wiring were
rewired but "the costs would be horrendous." He would settle for enhanced training for mechanics, restrictions on Kapton use
and perhaps some kind of electronic signals that could dampen stray electric signals sometimes associated with electrical
problems. Price and Block say that one problem with arc tracking is that the evidence is destroyed - either by the event or by a
fire if the plane crashes. That concern is given some support by a 1995 FAA study:
"Electrical Short Circuit and Current Overload Tests on Aircraft Wiring."
"The appearance of a wire subjected to a current that totally degrades the insulation looks identical to a wire subjected to a
fire," wrote Patricia Cahill, who conducted the tests and authored the report.
"It's the four-letter word nobody wants to talk about," said Ed Block. "W-i-r-e."
An explosive, arc-tracking event - also known as flash over - is a rare event. But such events and similar electrical malfunctions
have occurred in military and commercial aviation. There also is evidence that, even when flash over doesn't occur, arcing can
lead to stray signals that can cause control problems. The News Tribune examined more than 4,300 records from the Federal
Aviation Administration, the National Transportation Safety Board and the Department of the Defense.
Some incidents:
* Jan. 14, 1985: A new Monarch Airlines Boeing 757 flying over the Atlantic lost all main electrical power after an
electrical fire. The investigation, which found the fire was caused when toilet fluid leaked onto defective wire,
prompted Boeing to develop a safer wire (cause: arc tracking)
* July 30, 1985: A United Airlines DC-10 lost power in flight after chafed wires arced and exploded, spewing
molten copper within the wing and vaporizing foot-long stretches of wire (cause: arc tracking).
* March 30, 1987: A Navy F-18 fighter lost all instruments and main power after a bundle of electrical wires,
chafed from rubbing against a bolt, created a flash over, (cause: arc tracking), that spread to nine other bundles.
* May 11, 1990: A Philippines Air Lines Boeing 737 at Manila exploded as it was leaving the gate, killing eight
and seriously injuring 30. The investigation, centering on an explosion in the nearly empty center fuel tank, found
"numerous areas in which wire insulation had been damaged." (cause: arc tracking)
* July 17, 1996: A TWA Boeing 747 exploded off Long Island, killing all on board. While the crash remains
under investigation, attention has focused on what caused the vapors in the nearly empty central fuel tank to
explode. (cause: unknown at this time)
The FAA has ordered inspections for burned or chafed wiring in outboard fuel tanks and auxiliary tank jettison
pumps in all 747s. The FAA also ordered repetitive inspections for corrosion or degradation of the wire, insulation
and wire terminal assembly in 747 and 757 fuel boost pumps. Such deterioration, the FAA said, could cause both
arcing and a fuel leak.<<
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