Canadians Close the Book on Swissair 111

Aviation Week Online (http://www.aviationnow.com) ^ | May 2003 | Richard N. Aarons

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Canada's Transportation Safety Board (TSB) has completed one of the most thorough aircraft accident investigations ever undertaken with a final briefing on the downing of Swissair Flight 111. Over the last four years, the TSB's activities have led to the removal of one type of flammable acoustic insulation from most transport aircraft and to dozens of safety recommendations dealing with electrical system certification, pilot training and aircraft component fire testing.

In the end, the TSB determined the Swissair crew was dealing with confusing cues and a hidden fire that propagated fast enough to overwhelm their generally appropriate decision-making. Nevertheless, it is instructive to review the story of the flight and the crew's actions when faced with an ambiguous smoke condition. The factual information below comes from the TSB's final report....

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This is the final word on the crash of a Swissair MD-11 with 215 passengers and 14 crewmembers on board off the coast of Canada, while enroute from New York's JFK to Geneva, Switzerland, on Sept 2, 1998. Nearly 98 per cent of the wreckage was recovered, and the exhaustive investigation rivaled the TWA 800 investigation, costing nearly 50 million dollars.

In the past the aviation community has been somewhat unsympathetic to the crew, since they took vectors away from the airport to which they decided to divert (Halifax) while they dumped fuel, while presumably the fire raged out of control. This article, in a detailed analysis, determines that the crew would not have been able to land at Halifax and execute an approach (which was not in their publications up front) while trying to deal with the fire and subsequent systems failures that compounded in the last three minutes (including radio failures and navigation instrument failures). They were too close to the airport to lose sufficient altitude without maneuvering off-course. The elapsed time from the moment they smelled smoke until they hit the water was 20 minutes, 40 seconds.

Basically this would have happened to any crew in the same situation. The fire was apparently caused by insulation that caught on fire because of arcing from some wiring hidden in overhead spaces just aft of the cockpit. There were no fire sensors in that particular area, and the checklists were not designed for this type of problem, that must be isolated immediately.