Flight 447 disappeared minutes after flying into an extremely dangerous band of storms Sunday night, but what exactly caused its electrical systems and cabin pressure to fail remains a mystery. The "black box" cockpit recorders could be miles below the surface of the Atlantic Ocean.
If they can't be recovered, investigators will have to focus on maintenance records and a burst of messages sent by the plane just before it disappeared. Officials have released some details of these messages, but a more complete chronology was published Wednesday by Brazil's O Estado de S. Paulo newspaper, citing an unidentified Air France source.
Air France and Brazilian military officials refused to confirm the report. But if accurate, it suggests that Flight 447 may have broken up thousands of feet in the air as it passed through a violent storm, experts told The Associated Press.
The report said the pilot sent a manual signal at 11 p.m. local time saying he was flying through an area of "CBs" - black, electrically charged cumulo-nimbus clouds that come with violent winds and lightning. Satellite data has shown that towering thunderheads were sending 100 mph (160 kph) winds straight into the jet's flight path at that time.
Ten minutes later, the plane sent a burst of automatic messages, indicating the autopilot had disengaged, the "fly-by-wire" computer system had been switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm also sounded, indicating the deterioration of flight systems, according to the report.
Three minutes after that, more automatic messages indicated the failure of two other fundamental systems pilots use to monitor air speed, altitude and direction. Then, a cascade of other electrical failures in systems that control the main flight computer and wing spoilers.
The report repeats a detail previously released by Brazil's Air Force: that the last message came at 11:14 pm, indicating loss of air pressure and electrical failure. The newspaper said this could mean sudden de-pressurization, or that the plane was already plunging into the ocean.
Air France spokesman Nicolas Petteau referring questions about the report to the French accident investigation agency, BEA, whose spokesman Martine Del Bono said the agency won't comment.
Brazil's Defense Minister Nelson Jobim also declined to comment on the report, saying "that investigation is being done by France, Brazil's only responsibility is to find and pick up the pieces."
France's defense minister and the Pentagon have said there were no signs that terrorism was involved, and Jobim said "that possibility hasn't even been considered."
The fierce thunderstorms, turbulence, lightning or a catastrophic combination of events could have broken apart the plane, aviation experts have said. And while the messages reported by the newspaper don't indicate why the aircraft went down, they strongly suggest it broke apart in the air, said Bill Voss, president and CEO of the Flight Safety Foundation in Alexandria, Va.
"These are telling us the story of the crash. They are not explaining what happened to cause the crash," Voss said. "This is the documentation of the seconds when control was lost and the aircraft started to break up in air."
Voss stressed that the messages alone were not enough to understand why the Air France jet went down, noting that the black boxes will have "far more parameters" that could determine the cause.
The new debris was discovered about 90 kilometers (55 miles) south of where searchers a day earlier found an airplane seat, a fuel slick, an orange life vest and pieces of white debris. The original debris was found roughly 400 miles (640 kilometers) northeast of the Fernando de Noronha islands off Brazil's northern coast, an area where the ocean floor drops as low as 22,950 feet (7,000 meters) below sea level.
Brazil was leading the search, while France took charge of the crash investigation, working with Air France, Airbus and meteorologists to determine what happened.
And while four boats and a tanker ship were en route to the scene, they were slowed by high seas. "We have four divers on the way, but the first of them will not get to the scene until midday Thursday," a Brazilian navy spokeswoman said Wednesday, speaking on condition of anonymity.
Brazil lacks the equipment needed to reach the ocean floor, she added, so if the black boxes are at the bottom of the sea, their recovery will have to wait for the arrival early next week of a French research ship with remotely controlled submersibles that can explore as deeply as 19,600 feet (6,000 meters).
The sturdy black boxes - voice and data recorders - are built to give off signals for at least 30 days, even underwater, and could keep their contents indefinitely.
But the head of France's accident investigation agency, Paul-Louis Arslanian, said in Paris that he is "not optimistic" about recovering the recorders - and that investigators should be prepared to continue the probe without them.
"It is not only deep, it is also mountainous," he said. "We might find ourselves blocked at some point by the lack of material elements."
A French AWACS radar plane and two other French military planes flew Wednesday over the area where debris was found to better narrow down the search zone. A U.S. Navy P-3C Orion surveillance plane - which can fly low over the ocean for 12 hours at a time and has radar and sonar designed to track submarines - also joined the operation.
Arslanian said investigators didn't have enough information to determine whether the plane broke up in the air or upon impact with the sea, and that in the absence of black box data, they are studying maintenance and other records.
"For the moment, there is no sign that would lead us to believe that the aircraft had a problem before it took off," Arslanian said.
He said investigators did not know the exact time of the accident or whether the chief pilot was at the controls when the plane went down. Pilots on long-haul flights often take turns at the controls to remain alert.
While some experts questioned whether a bolt of lightning alone could bring down an Airbus A330, Mary Schiavo, former inspector general for the U.S. National Transportation Safety Board, said it was plausible.
"For this plane, the difference could have been if the lightning hit a fuel tank or got inside and took out the electrical system," Schiavo said on CBS' "The Early Show. "It's like an atom bomb."
If no survivors are found, it would be the deadliest crash in Air France's history, and the world's worst civil aviation disaster since the November 2001 crash of an American Airlines jetliner in the New York City borough of Queens that killed 265 people.
Hundreds of relatives grieved deeply for those who were lost, a roster that included vacationers, business people, and an 11-year-old boy traveling alone back to England.
Brazil is holding three days of national mourning, and French President Nicolas Sarkozy was joining relatives at a service at Notre Dame Wednesday.
"We will miss your dancing feet," read a tribute from the Northern Ireland family of Eithne Walls, 29, a dancer-turned-doctor. "We will miss your silliness, your wit and your hugs. We will always hold you in our hearts and you are never truly gone."
---
Alan Clendenning wrote from Sao Paulo. Associated Press writers Bradley Brooks in Rio de Janeiro; Marco Sibaja in Brasilia;Slobodan Lekic in Brussels, Belgium; Shawn Pogatchnik in Dublin; Emma Vandore in Bourget, France; and Angela Charlton in Paris also contributed to this report.
Get Action News on your website
