Air France 447 - Brazilian Official Says Fire Unlikely in Airbus Crash
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WASHINGTON — As the Brazilian air force on Thursday recovered the first piece of floating debris in the Atlantic Ocean from the Air France jet that crashed with 228 on board, more questions than answers were emerging over how and when the Airbus A330 may have broken apart.
The Brazilian air force Web site reported that a helicopter crew extracted a structural support piece about eight feet long — which might have come from the jet’s cargo hold — about 340 miles northeast of Brazil’s Fernando de Noronha islands.
So far, the scant physical evidence from the crash has not helped investigators determine a cause.
A senior Brazilian military official said that a 12-mile-long fuel slick found on the surface of the ocean seemed to rule out a mid-air fire or explosion as the cause of the disaster.
But a pilot for Air Comet who was flying in the vicinity on Sunday night told the Spanish newspaper El Mundo in Thursday’s edition that he saw a bright flash of white light at the same time the Air France Flight 447 disappeared about 700 miles off the coast of Brazil on its way from Rio de Janeiro to Paris.
The chief executive of Air France, Pierre-Henri Gourgeon, said at a private meeting with families that the plane disintegrated either in the air or when it slammed into the ocean, and that and there were no survivors.
In acknowledging that it had found more debris on Thursday, news reports quoted a Brazilian military official as saying the color suggested it was internal parts of the plane.
“We don’t know if it’s the fuselage, (but it’s) probably internal because we found brown, white and two yellow bits,” Ramon Borges Cardoso, the director of the Air Space Control Department, said on Brazil’s Terra web site. “That doesn’t correspond to the external part of the airplane but rather the internal part, where you have the baggage hold, seats and covers.”
Mr. Cardoso said ships in the area were collecting debris to take to the operations base in Fernando de Noronha, a 12-hour round trip.
Experts are questioning whether extreme turbulence, a direct lightning strike, the speed of the aircraft during the stormy weather, or a pre-existing problem with the plane might have caused it to break up only four hours into the 11-hour flight.
Without the black boxes containing the plane’s voice and data recorders — which officials say may never be recovered the from the ocean — the only clues besides the scant debris exist in the series of 10 satellite signals.
The pilot sent a manual signal at 11 p.m. local time indicating that the plane was passing through an area of black, electrically charged cumulonimbus clouds, usually containing lightning and violent winds, according to The Associated Press. The news service, quoting an unidentified aviation official, presented a chilling timeline of events in the cockpit that reveal the plane’s ensuing problems within a 14-minute span, but not what caused them.
About 10 minutes after the manual signal, the plane sent out a series of automatic messages to indicate the autopilot had disengaged, a computer system had switched to alternative power and that controls to keep the plane stable had been damaged. About three minutes later, more automatic messages reported the failure of systems to monitor air speed, altitude and direction.
The last automatic message, which was received at 11:14 p.m. local time, signaled a loss of cabin pressure and complete electrical failure.
The system controlling these automatic signals, installed on all newer Airbus models, does not indicate the airplane’s location. Rather, it is designed to speed maintenance efforts by alerting maintenance technicians on the ground to problems before a plane lands, so they can be cleared up without delaying the next flight.
William R. Voss, president of the Flight Safety Foundation in Alexandria, Va, said in a telephone interview Thursday that the pattern of debris could indicate an in-flight break-up. Big debris that floats, Mr. Voss said, is generally not a flat sheet of aluminum, like part of the fuselage, but a more box-like structure, often the tail, and the tail often comes off first.
In this case, he said, searchers have come upon a big floating piece that was on the airplane’s likely track, indicating that it separated from the plane at high altitude, early in the event.
He noted that what was first reportedly radioed back from the automatic system was the auto pilot disengaging. This occurred, Mr. Voss said, either because a pilot saw something going wrong and took manual control or because the computerized auto pilot had a problem "and gave it back to him.”
"The sequence is pretty consistent with things going to hell from there,” he said.
Eleven planes and helicopters are involved in the search operation, the Brazilian military said, including a French ship with two remotely controlled submersible crafts that can be used to explore as deep as 19,600 feet and a United States Air Force P-3 Orion. A spokesman for the National Transportation Safety Board, Ted Lopatkiewicz, said his agency had worked with “civilian and military U.S. government agencies” to look for radar or satellite data for the area at the time of the crash but had not found any.
The federal safety board said late Wednesday that it would be part of the investigation; under international treaty, it will be involved because the engines were manufactured in the United States by General Electric. The role of the engines in the crash, if any, has not been determined.
But unlike other crash investigations that the agency joins, it will not be sending representatives, at least not yet. Peter Knudson, an agency spokesman, said that at the moment "there is no place to go."
In many international crashes, the safety board makes its laboratory available for deciphering the cockpit voice recorder and helps in interpreting the flight data recorder. But in this case, involving a French airline and a European-built plane, that work will probably be done in France, experts said.
The main value of the debris found so far may be as a clue to the location of more important parts of the plane that are certain to have sunk, notably the black boxes. Each is equipped with a device that sends out an audio beep that in favorable conditions can be heard at 5,000 meters — about 3.1 miles. That signal begins to fade after 30 days.
The ocean is more than four miles deep in some parts of the area, and, while water is an excellent transmitter of sound, the sound waves are reflected at boundary layers where the water changes temperature, according to Duncan W. Schofield, a principal engineer at Honeywell, which built the boxes. Searchers can lower microphones to listen, but those are towed through the water at a a few miles per hour, increasing the need to narrow the search area.
Aviation experts said the flight data recorder was designed to track more than 400 categories of data, including the strength of turbulence and the functioning of various cockpit systems. And the cockpit voice recorder, if recovered, would indicate who was in the cockpit.
More than four hours into the flight, the captain, who is required to be at the controls for takeoff and landing, would typically have gone off for dinner and a nap, according to airline experts, leaving a relief pilot and the first officer at the controls, both typically less experienced but well qualified for what is ordinarily a very quiet phase of flight.
The plane was flying through an area of powerful thunderstorms, but there is no clear indication that the weather was unusual for the region.
“I don’t see anything unusual about these storms,” said Timothy A. Vasquez, a former Air Force meteorologist whose company, Weathergraphics, published a Web page showing the plane’s path and satellite data of storm intensity at the time of the crash. “Planes have flown through a lot worse; I’ve seen worse squall lines in Kansas and Missouri,” he said.
Matthew L. Wald reported from Washington, and Liz Robbins from New York. Reporting was contributed by Alan Cowell from London, Matthew Saltmarsh and Maïa de la Baume from Paris, Sharon Otterman from New York, and Andrew Downie from São Paulo, Brazil.
