Novel Dunia

There are few mysteries as puzzling as an airplane lost at sea.

Strewn over miles of ocean surface or buried under thousands of feet of water, airplane wreckage can take months to retrieve and years to understand.

"The Atlantic Ocean is a huge place," aviation-safety consultant John Cox said.

That vastness has now engulfed Air France Flight 447, which disappeared into the Atlantic darkness Sunday night after flying into a wall of thunderstorms and turbulence.

An airplane seat, a life jacket, metallic debris and signs of fuel were found in the middle of the Atlantic Ocean on Tuesday by Brazilian military pilots searching for the missing Air France airliner.

The debris was spotted from the air about 410 miles north of the Brazilian island of Fernando de Noronha, roughly along the path that the jet was taking before it disappeared with 228 people on board, said air force spokesman Jorge Amaral.

There were no signs of life in two sightings of separate debris areas about 35 miles apart.

"The locations where the objects were found are towards the right of the point where the last signal of the plane was emitted," Amaral said. "That suggests that it might have tried to make a turn, maybe to return to Fernando de Noronha, but that is just a hypothesis."

Amaral said authorities would not be able to confirm that the debris is from the plane until they can retrieve some of it from the ocean for identification. Brazilian military ships are not expected to arrive at the area until Wednesday.

Former National Transportation Safety Board chairman Jim Hall likened finding the missing plane to "trying to find a needle in a haystack," he said.

Hall oversaw the investigations and water recoveries of TWA Flight 800, which crashed a few miles off the Long Island coast in 1996, and of EgyptAir Flight 990, which crashed 60 miles from Nantucket in 1999. Those investigations were less daunting than the search for Flight 447 but were still difficult. Wreckage was in several hundred feet of murky water that impaired visibility, and shifting currents moved pieces around, Hall said.

Most airplane crashes occur during takeoff or landing, putting the wreckage either on the ground or in shallow water, said Bill Voss, head of the non-profit Flight Safety Foundation. "It's very unusual to have an aircraft encounter a problem while it's cruising," Voss said.

The search for wreckage will strain relatives of passengers. "It's going to be very traumatic for the victims' families because they're going to want to know something as soon as possible for closure," said Cox, who is CEO of Safety Operating Systems, an aviation consultant in Washington, D.C. "A lot of victims' families will hold out hope."

The probe of Flight 447 will depend on several factors, aviation-safety experts said:

•Finding and retrieving wreckage. If Flight 447, a wide-body Airbus 330-200, crashed into the ocean intact, pieces could be spread over several miles. But if the plane came apart at 35,000 feet, "you could have debris scatter a couple of hundred miles," said Bill Waldock, an air-crash expert at Embry-Riddle Aeronautical University. "The currents could carry parts of the airplane a long, long ways away."

When the cargo door blew off a United Airlines flight in early 1989, killing nine people, the investigation wasn't resolved until the door was retrieved from the bottom of the Pacific Ocean— 17 months later.

"Few ships around the world have the capability not only to explore and map the bottom of the ocean, but also to bring up significant amounts of wreckage," said Todd Curtis, head of the Airsafe.com Foundation, which promotes aviation safety.

•Cooperation in the search effort. Flight 447 appears to have crashed in international waters and had passengers from 32 countries on board, including 61 French citizens, 58 Brazilians, 26 Germans and two Americans. Although France, where the airplane was registered, will lead the investigation, other countries will have a strong interest, particularly Brazil because of the number of Brazilian passengers, Waldock said.

The U.S. National Transportation Safety Board will send experts to help the investigation because the engines on Flight 447 were made by GE Aviation, a division of U.S.-based General Electric, board spokesman Peter Knudson said.

"Anytime you have multiple-country investigations, that makes it a little more complex," Waldock said.

•Retrieving the flight data recorders. Such recorders can be separated from the beacons that send out homing signals to search crews, meaning it's possible that the boxes could never be found at the bottom of the ocean.

When a China Airlines 747 crashed into the Taiwan Strait in 2002, it took 24 days to find the recorders.

Currents and deep water also could make recovery difficult, said Michael Barr, who teaches aviation safety at the University of Southern California. "If they don't locate it within 72 hours, the information is going to be hard to get. After three days, the ocean currents can spread wreckage all over the place."

Although safety experts discounted the possibility that lightning brought down Flight 447, several said that storms and winds that accompany lightning could have severely damaged the 4-year-old plane or caused pilots to lose control.

Aircraft wiring expert Ed Block said in-flight turbulence could cause electrical wires to rub against one another, cracking the wire insulation and leading to an electrical failure or fire. From 1999 to 2004, Block was part of a Federal Aviation Administration advisory group that inspected planes for cracked wiring.

Flights such as the Airbus 330 that crashed have many more miles of electrical wiring because of their in-seat video systems, Block said. Passengers on Airbus 330s can select from among 85 movies to watch on individual monitors at their seats.

Even if the investigation drags on, time is important, experts said. "The investigative process is slow and methodical," said Cox, the safety consultant. "It's most important to be right than fast."

LIST OF PASSENGERS ABOARD LOST AIR FRANCE FLIGHT

Some of the passengers aboard Air France Flight 447, which disappeared over the Atlantic Ocean en route from Rio de Janeiro to Paris carrying 228 people:

Luiz Roberto Anastacio, 50; Brazilian; president for South America, Michelin

Aisling Butler, 26; Irish, of Roscrea, Ireland; doctor

Brad Clemes, 49; Canadian from Guelph, Ontario; Coca-Cola executive

Arthur Coakley, 61; British; structural engineer for PDMS

Jane Deasy, 27; Irish; doctor

Pedro Luis de Orleans e Braganca, 26; Brazilian; descendent of Brazil's last emperor

Antonio Gueiros; Brazilian; information systems director, Michelin

Michael Harris, 60; American, formerly of Lafayette, La.; geologist

Anne Harris; American, formerly of Lafayette, La.

Zoran Markovic, 45; Croatian, from Kostelji, Croatia; sailor

Christine Pieraerts; French; engineer at Michelin

Eithne Walls, 29; Irish; doctor