Damaged Wiring Found in Older Planes
Wednesday, August 23rd 2000, 12:00 am
By: News On 6
WASHINGTON (AP) â€” Wiring damage of the type that could have caused the TWA Flight 800 disaster has been found in other aging aircraft, federal investigators said Wednesday.
A four-year investigation of the crash of the Boeing 747 New York-to-Paris flight led to a conclusion that it was caused by an explosion of vapors in a fuel tank of the 25-year-old plane. Although a solid body of circumstantial evidence points to an electrical short as the cause of the explosion, insufficient wire was recovered to know for sure, said Robert Swaim of the National Transportation Safety Board.
But the investigation led to discovery of damaged wiring in other older planes, Swaim told a hearing.
``We looked at other planes from other carriers and other countries,'' Swaim said. Inspectors found worn insulation, improper wiring repairs, opened splices that should have been sealed and lint on circuit breakers.
In some cases, he added, wiring had been damaged by chemicals such as anti-corrision spray and overflow from lavatories.
Wiring checks in 25 airlines â€” some old, some new â€” found that ``all had some kind of foreign material except for one new 737,'' Swaim said.
NTSB Chairman Jim Hall said the longer a plane files, the more changes and modifications it needs. He said he is not sure the industry is paying enough attention to that issue.
But Bernard Loeb, aviation safety director for NTSB, cautioned that investigators are ``not saying the problem has reached the level of planes being unsafe. ``We found problems and they need to be addressed,'' he said.
As a result of the TWA crash, Swaim said, the Federal Aviation Administration has formed a task force to develop improved maintenance procedures for aging aircraft.
Swaim's conclusion that a fuel-tank explosion destroyed TWA Flight 800, killing all 230 people abroad off Long Island, N.Y., was announced at the first day of the hearing Tuesday.
He spent four years looking for the source of ignition of the explosion. ``I would love to walk in here with a molten piece of wire and say, ``Here it is,''' he said.
A number of possible causes of the explosion were considered, including problems with the main landing gear, static electricity, a small explosive charge, a missile and a meteorite strike, he said.
Investigators zeroed in on the short circuit because of a combination of factors which, taken together, were telling. A crew member was recorded on the cockpit voice recorder remarking on the fuel flow indicator swaying crazily shortly before the crash. A buzz on the cockpit voice recorder went silent in the moments before the crash. Additionally, there had been recent problems with lights on the plane.
While wiring inside the fuel tank is very low voltage those wires are bundled together with higher voltage wires and a short could have been carried into the fuel tank, investigators said.
Air and fuel had been heated by an air conditioner positioned underneath the tank while the plane was delayed for three hours prior to takeoff. That helped to make the tank volatile when it climbed in altitude, NTSB investigator Joseph Kolly said.
Given those conditions, a spark as weak as the static electricity transferred between a person's hand a metal doorknob would have been sufficient for an explosion, Kolly said.
TWA Flight 800 went down shortly after leaving New York's John F. Kennedy Airport on July 17, 1996, bound for Paris.
The crash has spawned a host of conspiracy theories, the most prevalent being that a bomb or a missile brought down the plane.
Some still contend the government is trying to cover up the real cause, and one group, calling itself the TWA 800 Eyewitness Alliance, ran a full-page ad in Tuesday's Washington Times insisting missiles were to blame.
Hall on Tuesday chastised those who continue to push those theories. The FBI, the Bureau of Alcohol, Tobacco and Firearms and his investigators all failed to find evidence of a bomb or missile blast, he said.
Loeb said that bomb and missile blasts leave distinct patterns.
``High-energy explosions leave distinctive damage signatures such as severe pitting, cratering, hot gas washing, and petaling. No such damage was found on any portion of the recovered airplane structure,'' Loeb said.
The physical evidence ``leads to the inescapable conclusion that the cause of the in-flight breakup of TWA Flight 800 was a fuel-air explosion inside the center wing tank,'' Loeb said.
John Seaman of Albany, N. Y., who lost his 19-year-old niece Michelle Becker of St. Petersburg, Fla., was at the hearing in Washington, along with more than 75 relatives of victims.
``This speculation still that this was a missile is making all of us crazy,'' Seaman said. ``It makes us feel like there is someone walking around today laughing about the death of our loved ones. If all they can come up with is a probable cause then that is all that can be done.''
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