Investigators implicate entertainment system wiring in Swissair crash
Thursday, March 27, 2003
HALIFAX (CP) - Wiring that powered a controversial entertainment system combined with highly flammable insulation to feed a deadly fire that brought down Swissair Flight 111 off Nova Scotia in 1998, investigators said Thursday.
In releasing its final report into the country's longest and costliest accident investigation, the Transportation Safety Board didn't identify the exact source of a fire that caused a massive electrical failure on the MD-11, but concluded it was linked to the improperly installed gaming system.
The 338-page document outlined a fateful sequence of events that started when wire began arcing in a hidden area above the cockpit ceiling.
"This particular arc site was found on one of the wires that supplied power to the inflight entertainment network," lead investigator Vic Gerden said at the release of the report into the Sept. 2, 1998, crash that killed 229 people.
The arcing - a phenomenon in which a wire's coating is corroded and can lead to sparking - ignited a flammable insulation covering, allowing the fire to race through the plane's wiring system.
"It is important to emphasize that without the presence of this and other flammable materials, this accident would not have happened," Gerden said, holding up a pillow-sized piece of the metallic insulation.
The board recovered 20 pieces of wire from the plane that showed melted copper, indicative of arcing damage. At least one of the damaged wires was from the entertainment unit, but others were retrieved from the wreckage, leading investigators to believe it was likely not the only wire involved in the arcing.
"We strongly suspect that at least one other wire was involved, either an aircraft wire or another entertainment system wire," Gerden said.
The TSB, charged with determining cause and issuing safety recommendations, also implicated the powerful U.S. Federal Aviation Administration for failing to ensure the entertainment system was installed and certified properly.
The program, which allowed passengers in the first-class section 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.
Officials said the FAA, which sets international aviation standards, distanced itself too much from the installation of the entertainment unit, which was unique to Swissair's fleet.
As part of its 23 recommendations, the TSB called for increased scrutiny in the certification of systems added to aircraft.
"The FAA failed in every respect to ensure the safety of the 229 people that boarded that aircraft," said Lyn Romano, whose husband Ray was on board the flight.
Les Dorr, a spokesman for the FAA, said the group has already begun looking into the process since media reports surfaced about the installation being rushed and safety concerns overlooked.
Miles Gerety, whose older brother Pierce died in the crash, said he has no doubt the entertainment system caused the sparking that led to the fire and crash.
"I do believe the TSB has found the cause of the crash," said Gerety, a lawyer from Bridgeport, Conn., and one of a handful of family members who made the trip to Halifax.
Investigators also determined the pilots acted appropriately in not trying to land the plane immediately, something critics have argued could have saved some or all of those on board.
The pilots spent valuable minutes trying to identify the source of the fire after smelling smoke 53 minutes into the flight. They initially thought it was coming from the air conditioners, a normally benign occurrence that wouldn't haven't warranted an emergency landing.
Their instrument panel didn't indicate problems with the electrical system, leaving them fatally unaware of the fire that was spreading rapidly outside the cockpit.
The pilots, one a veteran flyer, also didn't know the area over their heads was lined with the flammable insulation. This lack of information led them to believe they had time to go through a lengthy checklist to determine the source of the smoke, and prepare for a precautionary landing.
Heavy with fuel for the trip from New York to Geneva, they diverted away from the Halifax airport to dump fuel over the ocean.
The board did a theoretical "descent profile" and found the pilots would not have been able to bring it down safely in Halifax.
"Even if the pilots could have foreseen the eventual deterioration due to the fire, because of the rapid progression of the fire they would not have been able to complete a safe landing in Halifax," Gerden said.
He said the pilots would have been battling smoke and heat in the cockpit and that parts of the ceiling had likely given way, creating a horrifying environment for the crew.
Moments later, they lost all communications and most of their navigation capabilities. The crippled aircraft then got locked in a steep, right-banked turn and dove into the ocean at a speed of 350 mph.
The agency, which has spent $57 million and 4ï¿½ years examining millions of pieces of wreckage, issued nine new recommendations. Two address testing and flammability standards of thermal acoustic insulation materials.
The material, known as metallized polyethylene terephthalate, has been removed from all commercial planes in Canada. About 700 American jetliners are still lined with the insulation and have until 2005 to have it replaced.
It also recommended improved certification standards for planes' add-on systems, such as the entertainment system.
Four recommendations propose improvements to how information from the flight data and cockpit voice recorders is captured and stored.
The board has released several recommendations and advisories over the course of the investigation. They have included calls for more stringent testing of electrical wiring in aircraft, inspection of cockpit wiring of all MD-11s and independent power sources for flight recorders.
Alison Auld gets credit in my book for getting the headline right.
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