mandag 3. september 2018

Swissair 111 - 20 år siden - Curt Lewis

How the Swissair Flight 111 tragedy changed airline safety
Twenty years after Swissair Flight 111 killed 229 people off the coast of Nova Scotia, the investigation into the deadly crash continues to have an enduring legacy on safety in the airline industry around the world.

Vic Gerden led the 4.5-year, $57-million Transportation Safety Board investigation into the worst aviation disaster ever in Canadian airspace to try and piece together the millions of fragments from the destroyed jetliner.


"We recovered a couple of million pieces, but some of the pieces were so small that it was a challenge to reassemble them properly," Gerden told Global News on the 20th anniversary of the crash. "There are also 165 miles of wire and much of those pieces were in small pieces that were perhaps a metre in length.

"It was a challenge to put it all together, but at the end of the day, I believe we ended up with a very thorough, unbiased and a fully accepted report."

Investigators conducted tests at labs in the U.S., Switzerland, Germany and Canada as part of the technical investigation into the crash, which involved reconstructing parts of the shattered plane.

"All of that takes a great deal of time and in the process, we also attempted to determine what ... were the safety deficiencies that led to this accident," he said.

RCMP Sgt. Duane Cooper worked on the investigation and remembers the challenges in recovering parts of the 500,000-pound plane, discovered roughly 55 metres below the Atlantic Ocean.

"We had to devise different ways to get all those pieces from the bottom of the ocean into CFB Shearwater so that we could actually do an accident investigation with the transportation safety board," Cooper told Global News.

Cooper said that is was imperative to recover every scrap of evidence. Eventually, 98 per cent of the aircraft was recovered.

"A piece could be as small as a dime, or it could be as large as half this room. Everything from engines from the plane all the way down to little pieces of wiring," he said. "Even little pieces of wiring they determined would be important potentially as evidence in the investigation."

In the days and weeks after the crash, the families were given daily updates on the investigation, Gerden said. As the investigation dragged into the months and years, families of victims were allowed into the hanger where the wreckage reconstruction was being conducted whenever they visited Halifax.

"I think the families realized why it was taking an extended period of time and they were very supportive of the investigation and I'm certainly appreciative," he said.

On Sept. 2, 1998, the doomed flight left JFK international airport heading for Geneva, Switzerland, carrying 215 passengers and 14 crews members. Less than an hour into the flight, the two pilots detected the faint smell of smoke and declared "Pan Pan Pan" - an international signal indicating a problem that's not yet an emergency.

A sparking wire in the cockpit above and behind the pilots head had started a fire, igniting the flammable insulation that quickly disabled the plane and crept throughout the fuselage.

Audio from air traffic control tapes revealed the final desperate moments as pilots tried in vain, amid rapidly worsening fire conditions, to keep the plane in the air.

"Swissair one eleven heavy is declaring emergency," says one of the pilots, as the second pilot makes a simultaneous transmission: "We are declaring emergency now."

The plane struck the water just after 10:30 p.m. AT killing everyone on board.

In March 2003, the TSB has issued its final report that made 23 air safety recommendations, ranging from making airlines teach flight crews aggressive in-flight fire-fighting strategies, tougher aircraft wiring tests, and calls for emergency power sources to keep vital flight and voice recorders running.

Gerden said that as a result of the report, the industry now conducts much tougher flammability tests on materials used in aircraft and has removed metallized Mylar blanket insulation.

"Thermal acoustical insulation material was a large part of what fed the fire in that aircraft," he said. "Since then the certification standards for that material have been made more stringent, that particular material has been removed from about 1,500 airplanes and it's not allowed in future airplanes."

The report also recommended that pilots should try to land at the first sign of smoke, rather than trying to dump fuel, and that all aircraft systems, including oxygen, hydraulics and air conditioning, should be tested to see how they might contribute to a fire or how they might fail during a fire.

While the final report never concluded what part of the electrical wiring was at fault, a newly installed in-flight entertainment system was believed to be the culprit. Swissair, now defunct, removed the entertainment systems shortly after the accident.


Family members of victims of the crash of Swissair Flight 111 embrace as they pay respects on the deck of HMCS Goose Bay at the crash site off the coast of Nova Scotia on Nov. 28, 1998.

The TSB also cleared the crew of any wrongdoing as investigators determined that even if the plane had not diverted to dump fuel, it would still have been unable to reach Halifax.

Gerden left the TSB 13 years ago for the private sector and said the anniversary of the crash is still raw for many families.

"The families and loved ones had to deal with a terrible tragedy and I'm sure it's still not easy for them," Gerden said. "I do think about them."

But now 20 years after the crash, Gerden thanked the hundreds people involved in the multi-national investigation, including pilot associations, manufacturers, Swiss and U.S. airline investigators and countless individuals throughout Halifax.

"I take my hat off to them. Everybody did a really fine job to make the best of what was a tragedy," he said.

"I'm very proud of the work that was done by all of the responding organizations and by the transportation safety board investigators who put their hearts and souls into making sure that we did the best that could be done."

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