Air France 447 - France and Brazil Press Search for Missing Plane

Vice President Jose Alencar of Brazil spoke with the media after visiting relatives of missing passengers.

Working through the night, ships and aircraft from the French and Brazilian militaries continued to search Tuesday for the wreckage of an Air France jet that crashed in the Atlantic Ocean on Sunday evening during a flight from Brazil to France.

The Airbus A330-200, carrying 216 passengers and a crew of 12, apparently went down in a violent thunderstorm after encountering “very heavy turbulence,” Air France said.

French authorities said Tuesday that they had sent military reconnaissance planes from Senegal in West Africa to check reports from the pilot of a Brazilian civilian airliner that he had seen “orange dots” — possibly the glow of some fiery wreckage — on the ocean surface along the French plane’s possible flight path. But Christophe Prazuck, a French military spokesman, told the BBC it was “very unlikely” that anyone survived the crash.

“We will search all night long and keep going through dawn,” said Colonel Jorge Amaral of the Brazilian Air Force, quoted by the news service Agencia Brasil. “We have to work as if it were possible to find survivors.”

Air France said the passenger list, with 32 nationalities, included 61 French citizens, 58 Brazilians and 26 Germans.

Two Americans were on board, the company said, and CNN identified them as Michael Harris, 60, a geologist living in Brazil, and his wife, Anne Harris. Mr. Harris, originally from Greenville, South Carolina, worked for Devon Energy in Houston, according to a Greenville TV station. Mrs. Harris, 54, was from Lafayette, Louisiana, and the couple had lived in Rio de Janeiro since July 2008.

Air France Flight 447 encountered bad weather and turbulence about four hours after takeoff from Rio, and the company said an automated warning system on the 4-year-old plane beamed out a message about electrical problems 15 minutes later. The signals were not sent as distress calls, and they were not read for hours, until air traffic controllers realized that the plane’s crew had not radioed in on schedule.

As the search for the plane continued over a vast swath of ocean between Brazil and the African coast, experts struggled to offer theories as to how a well-maintained modern jetliner, built to withstand extreme electrical and physical buffeting, could have gone down so silently and mysteriously.

There were no suggestions that a bomb, a hijacking or sabotage was to blame.

Whatever of the plane’s final minutes was recorded in its black box may never be known, because it is presumably at the bottom of the Atlantic. As is common with transoceanic flights, it was too far out over the sea to be tracked on land-based radar from Brazil or Senegal. Whether its location was captured by satellite or other planes’ radar was not immediately known.

The plane was scheduled to arrive at Charles de Gaulle airport at 11:10 a.m. local time. Stricken relatives descended on Terminal 2D, where the airline established a crisis center.

President Nicolas Sarkozy of France said: “It’s a tragic accident. The chances of finding survivors are tiny.”

The flight took off from Rio de Janeiro at 7:30 p.m. local time (6:30 p.m. Eastern time), and its last verbal communication with air traffic control was three hours later, at 10:33, according to a statement from Brazil’s civil aviation agency. At that time, the flight was at 35,000 feet and traveling at 520 miles per hour.

The last communication from it came at 11:14 — a series of automatic messages indicating it had suffered an electrical-system malfunction. The Associated Press reported that it also suffered a loss of cabin pressure.

Brazilian officials said the plane disappeared over the Atlantic somewhere between a point 186 miles northeast of their coastal city Natal and the Cape Verde islands off Africa. The area is known as the “horse latitudes,” where the tropics of the Northern and Southern Hemispheres mix, sometimes creating violent and unpredictable thunderstorms that can rise to 55,000 feet, higher than commercial jetliners can go.

Experts were at a loss to explain fatal damage from lightning or a tropical storm, both of which jetliners face routinely, despite efforts to avoid them — as much out of concern for passengers’ nerves as for the planes’ safety.

Pilots are trained to go over or around thunderstorms rather than through them. Brigitte Barrand, an Air France spokeswoman, said the highly experienced pilot, a 58-year-old Frenchman, had clocked 11,000 flying hours, including 1,100 hours on Airbus 330 jets.

The two co-pilots, also French, were 37 and 32 years old, and both had thousands of flight hours in Airbus A330s, the company said.

“A completely unexpected situation occurred on board the aircraft,” Mr. Gourgeon, the Air France CEO, told France’s LCI television.

“Lightning alone is not enough to explain the loss of this plane, and turbulence alone is not enough,” he said. “It is always a combination of factors.”

By some estimates, jetliners are typically hit by lightning at least once a year. But the strike normally travels across the plane’s aluminum skin and out the tail or a wingtip. Passengers are insulated in the nonconductive, largely plastic interior, and vital equipment is shielded.

A loss of cabin pressure could suggest a break in the fuselage, but planes are built to withstand buffeting from a storm’s updrafts and downdrafts. It could also be a consequence of an electrical failure, if the plane’s air compressors stop working.

Large hailstones created by some thunderstorms have been known to break windshields or turbine blades, though pilots would be likely to rapidly report something like that.

The missing aircraft was relatively new, having gone into service in April 2005. Its last hangar maintenance check was on April 16, Air France said. No Airbus A330-200 passenger flight ever had a fatal crash, according to the Aviation Safety Network.

Hans Weber, head of the Tecop aviation consulting firm in San Diego, offered a hypothesis about the episode, based on his knowledge of severe losses of altitude by two Qantas jets last year.

The new Airbus 330 was a “fly-by-wire” plane, in which signals to move the flaps are sent through electric wires to small motors in the wings rather than through cables or hydraulic tubing. Fly-by-wire systems can automatically conduct maneuvers to prevent an impending crash, but some Airbus jets will not allow a pilot to override the self-protection mechanism.

On both Qantas flights, the planes’ inertia sensors sent faulty information into the flight computers, making them take emergency measures to correct problems that did not exist, sending the planes into sudden dives.

If the inertia sensor told a computer that a plane was stalling, forcing it to drop the nose and dive to pick up airspeed, and there was simultaneously a severe downdraft in the storm turbulence, “that would be hard to recover from,” Mr. Weber said.