Swissair report won't find one cause,
but many factors say experts

Critics cite the uncertainties of accident findings as being very indicative of the inadequacy of black box capabilities and non-provision of cockpit CCTV

TSB Public Notice on Swissair 111 Final Report Presentation
 

ALISON AULD
Canadian Press

Sunday, March 23, 2003


HALIFAX (CP) - Investigators who have pored over the wreckage of Swissair Flight 111 for more than four years aren't expected to produce a definitive cause of the crash, but will likely zero in on critical flaws that set off a devastating chain of events, experts say.

 

Among them is a controversial inflight entertainment system said to be a part of findings by the Transportation Safety Board, which will release its final report into the 1998 crash on Thursday.

Aviation experts who have followed the lengthy investigation say they'll be surprised if the program is not found to be a main contributor to the massive electrical failure that brought the jetliner down off Nova Scotia, killing all 229 people on board.

"The entertainment system, from an engineering background, was a power-hungry monster and it gobbled up a lot of energy, creating so much heat that they required a rebalancing of the air conditioners," Gerry Einarsson, a former Transport Canada engineer who specializes in avionics, said from Ottawa.

"I can't with any degree of evidence say it caused it, but there's a great deal of reason to suspect it."

Investigators know a fire that raced along wires crippled the jetliner by disabling its electrical system, but they have yet to clearly state its source and likely won't.

Einarsson, who has lobbied Ottawa to improve aviation safety, believes the entertainment unit is key to the fire. He says the system was so hastily installed on the MD-11 that the proper inspections weren't done to ensure it could operate safely in the air.

He and others blame the powerful American Federal Aviation Administration in part for allegedly shirking its duties in certifying the system - something they say the safety board should address in its report.

"I seriously doubt that the Canadians will go as far as I think they should, because of political reasons," says Bernard Loeb, the former head of the U.S. National Transportation Safety Board.
 


"If I was the Canadians, I'd be a little cautious about suggesting an FAA process has significant holes in it."

Critics allege the agency didn't pay close enough attention to the devices, the installers and the manufacturers even though concerns had been expressed about them.

The system, which allowed passengers to gamble, play video games and watch movies, was found on test flights to raise cabin temperatures and cause hard drives in the seats to fail.

Despite that, Swissair ordered the system to be installed on 21 of its planes - including the jetliner that would plunge into waters off Peggy's Cove just over an hour after leaving New York.

The system came into sharp focus in the days after the crash, when investigators recovered 21 short-circuited electrical wires, including at least seven that came from the system. A wire that shorts can cause a spark or fire that could ignite other materials.

Swissair, once one of the world's most elite carriers and now bankrupt, voluntarily disconnected the system three weeks after the crash as a "precautionary measure."

Myles Gerety, who lost his brother in the accident, said he doesn't expect the report to produce a single cause, but hopes it isn't linked to the gaming unit.

"If it started with that entertainment system, I'm going to be really upset because it just seems like such a frivolous thing to bring down a plane," he said from Connecticut before heading to Halifax for the report's release.

The TSB would not comment on its forthcoming report.

The report is also expected to mention Kapton wiring, a disputed insulation that has been banned in some U.S. military aircraft because of its propensity to chafe, crack or break down.

The safety board, which has spent more than $60 million on the investigation, recovered pieces of the charred wire near where the fire was thought to have started just behind the pilots in the ceiling.

The Kapton wire had arced, a phenomenon in which the outer insulation is cracked or chafed and the wire is exposed to another surface. Electrical sparks can escape and set off a chain reaction, burning along the wire almost like a fuse.

Even though the discovery helped narrow the possibilities, the difficulty for investigators was trying to determine which came first.

"We are attempting to assess whether the arcing was the cause of the fire or whether it resulted from the existing fire that then damaged the insulation on the wire," lead investigator Vic Gerden said in the months after the crash.

Ed Block, a wiring expert, is convinced it was the source.

 

"I have seen this wiring-cancer attack the military, the commercial fleet and the general aviation fleet," Block, a former U.S. Department of Defence employee, said Friday.

"I am hoping the TSB sends a clear message to the world about this hidden danger."

The FAA responded to the Swissair probe by ordering operators to inspect cockpit wiring on all MD-11s. But Block says manufacturers are still lining planes with faulty wiring and not closely inspecting existing wiring.

Others are hoping the safety board demands changes to the cumbersome checklist pilots go through when they encounter smoke in the cockpit.

The Swissair pilots spent close to 10 minutes going through a 208-step checklist after they detected smoke, eating up valuable time some say should have been spent in diverting the plane to the nearest airport.

The TSB issued a recommendation in 2000 that planes land quickly in the event of smoke and that checklists be streamlined. The board also recommended that metallized Mylar blanket insulation be reduced or eliminated after finding it helped feed the fire.

Einarsson doesn't think the report will find a sole cause because of the complexity of the investigation and the devastation to the plane, most of which was recovered from the ocean floor.

"I would love a smoking gun, but I don't think that will happen," he said.

"What they're being asked to do almost is to see a whole bunch of wires that have melted at the ends and discern which one failed first or why it failed."

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Safety recommendations made since the crash of Swissair Flight 111:

January 1999: Based on the Canadian board's investigation, the American flight safety agency asks the Federal Aviation Administration in the United States to inspect cockpit wiring on all MD-11 aircraft.

March 1999: The Canadian board recommends flight recorders have independent power sources and be able to record up to two hours rather than 30 minutes.

August 1999: The FAA orders metallized Mylar blanket insulation be replaced after it is found to be flammable. The Canadian board issued an advisory that Mylar use be reduced or eliminated.

September 1999: The FAA bans the inflight entertainment system used on Flight 111, calling it "not compatible with the design concept of the MD-11."

April 2000: Acting on a directive from Canadian investigators, the FAA orders map-reading lights on MD-11s inspected or shut off. In inspections of about 12 aircraft, flammable Mylar blanket insulation was found pressed against many of the lights and showed signs of heat damage.

April 2000: The FAA issues eight safety orders concerning MD-11 electrical systems, bringing to over 30 the number of airworthiness directives released since the crash.


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