Doomed Air France Flight 447’s last terrifying few minutes in the air have already been pieced together by accident investigators.
Aviation sources in France said automated messages sent by the plane’s systems had allowed them to reconstruct events which appeared to show the Airbus broke up in mid-air as it flew through a hugely violent storm carrying 228 people.
The pilot sent a manual signal at 11pm local time saying he was flying through an area of CBs – electrically charged cumulonimbus clouds that come with violent winds and lightning.
Satellite data has shown that towering thunderheads were sending 100 mph updraft winds into the jet’s flight path at the time, several hundred miles of the coast of Brazil.
Ten minutes later, a cascade of problems began: automatic messages to Air France HQ indicate the autopilot had disengaged, a key computer system switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm sounded indicating the deterioration of flight systems.
Three minutes after that, more automatic messages reported the failure of systems to monitor air speed, altitude and direction. Control of the main flight computer and wing spoilers failed as well.
The last automatic message, at 11:14pm, signalled loss of cabin pressure and complete electrical failure – catastrophic events in a plane that was likely already plunging toward the ocean.
“This clearly looks like the story of the aeroplane coming apart,” the airline source said. “We just don’t know why it did, but that is what the investigation will show.”
The French accident investigation agency BEA refused to comment on the findings, as did Brazil’s defence minister Nelson Jobim who said the “investigation is being done by France; Brazil’s only responsibility is to find and pick up the pieces”.
Other experts agreed that the automatic reports of system failures on the flight from Rio to Paris strongly suggest it broke up in the air, perhaps due to fierce thunderstorms, turbulence, lightning or a catastrophic combination of events.
Meanwhile today, a US surveillance plane, a French Awacs radar plane and two other French military planes joined Brazil’s Air Force in trying to spot debris and narrow the search zone.
Mr Jobim said debris discovered so far was spread over a wide area, with some 140 miles separating pieces of wreckage they have spotted.
The floating debris includes a 23-foot chunk of plane and a 12-mile-long oil slick. Air Force spokesman Colonel Jorge Amaral said.
“Oil stains on the water might exclude the possibility of an explosion, because there was no fire,” Mr Jobim said.
The new debris was discovered about 55 miles south of where searchers a day earlier found an plane seat, a fuel slick, an orange life vest and pieces of white debris.
The original debris was found roughly 400 miles north-east of the Fernando de Noronha islands off Brazil’s northern coast, an area where the ocean floor drops as low as 22,950 feet below sea level.
Brazil lacks the equipment needed to reach the ocean floor. 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.
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.
However, 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.”
Mr 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,” Mr Arslanian said.
Air France today told passengers’ families officially to abandon any hope of survivors.
Chief executive Pierre-Henri Gourgeon told the families that the plane broke apart either in the air or when it slammed into the ocean’s surface.
Guillaume Denoix de Saint-Marc, who was asked by Paris prosecutors to help counsel family members, said: “What is clear is that there was no landing. There’s no chance the escape slides came out.”