Changes In Flight Recorders Possible -- Missing Data From Crash May Prompt New Rules
Seattle Times Aerospace Reporter
A joint recommendation addressing premature failure of flight recorders, inspired by the crash of Swissair Flight 111, could come from the transportation-safety boards of the U.S. and Canada, their chairmen said in Seattle yesterday.
Neither Jim Hall of the U.S. nor Benoit Bouchard of Canada specified what changes might be recommended to regulatory agencies in their respective countries.
But they said they are concerned that both the flight-data recorder and the cockpit-voice recorder on Flight 111 ceased operating six minutes before the Boeing MD-11 trijet hit the water near Nova Scotia on Sept. 2, killing 229.
Hall and Bouchard were in Seattle for a meeting with colleagues from six other nations. All are members of the International Transportation Safety Association, an organization that advocates independent investigative agencies and international cooperation.
"We lost six minutes - why?" said Bouchard, chairman of the Transportation Safety Board of Canada. "We will work closely with the NTSB and possibly a recommendation can come quickly to ask the FAA or Transport Canada to do something."
In the United States, Hall's National Transportation Safety Board would make recommendations to the Federal Aviation Administration, which could agree to issue an airworthiness directive calling for changes in, for example, how flight recorders are powered.
Both of the Flight 111 recorders were powered by the same electrical circuit, Hall noted.
Without those final minutes of information, "What we are left with is the wreckage of the aircraft, as well as what other information can be put together, and it makes the entire investigation much lengthier, which is difficult for the families and those interested in the safety of the particular aircraft. It also makes it more costly," Hall said.
It wasn't the first time valuable data about the last minutes of a doomed flight were lost. The flight recorders aboard a SilkAir 737 were somehow disabled before the plane plunged from 35,000 feet over Indonesia last December. Investigators speculate the captain might have turned off power to the recorders to hide his suicide.
In the case of the Swissair crash, investigators are looking closely at the possibility an onboard fire was started by a wiring problem, but other possibilities exist. Short-circuited wires could cause a power failure.
The crew reported the presence of smoke to air-traffic controllers before declaring an emergency. Contact was lost as crew members dumped fuel for an emergency landing in Halifax, Nova Scotia.
Chuck Taylor's phone message number is 206-464-2465. His e-mail address is: firstname.lastname@example.org.
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