RECIFE, Brazil – Brazilian search teams on Thursday scoured choppy Atlantic waters for remains of a crashed Air France jet after the first debris retrieved by helicopter turned out to be trash.

With hopes of finding any bodies waning as the search headed into its fifth day, Brazil's military shifted focus to recovering wreckage from the Airbus A330-200 crash that killed 228 people.

The New York Times reported that Airbus issued a warning on Thursday to airlines that pilots should follow established procedures if they suspect airspeed indicators are not working.

The warning followed a flurry of speculation that the plane may have crashed because it few into a storm too fast. But Brazilian and French officials cautioned that the evidence was far too slim to offer explanations.

With each passing moment the possibilities of finding bodies decreases, Brazilian Air Force Brigadier Ramon Borges Cardoso told reporters in Recife, the coastal city where wreckage from the crash would be brought.

We were initially concentrating on searching for bodies and survivors, but now we're focused on finding debris that can help in the investigation, he added.

The New York Times said Airbus told clients there was inconsistency between the different measured airspeeds in the Airbus 330 that crashed, though the company noted it was not prejudging the investigation's outcome.

Other reports from the Wall Street Journal and France's Le Monde both pointed to air speed, combined with thunderstorms in a notoriously dangerous tropical area, as a potential factor in the crash that has baffled aviation experts.

Airbus earlier declined to comment.

A luggage pallet and two buoys were pulled by helicopters from the crash area about 1,100 km (680 miles) northeast of Brazil's coast, but investigators later determined they weren't part of the jet.

MOURNING IN RIO

Searchers have found several debris sites spread out over 90 km (56 miles), a sign the plane may have broken up in the air. Cardoso said they have yet to collect any debris from the Airbus.

Air France Flight 447 was en route to Paris when it plunged into the Atlantic four hours after leaving Rio de Janeiro.

Eleven air force planes have been searching over a 6,000 sq km (2,300 sq mile) area from a base on the islands of Fernando de Noronha, off Brazil's northeastern coast.

Several hundred relatives and friends of the passengers crammed into the Candelaria church in Rio on Thursday morning, crying and hugging each other.

Those who are missing are here in our hearts and in our memories, French Foreign Minister Bernard Kouchner told them.

Experts have been mystified by the sudden crash of a modern airliner operated by three experienced pilots. Determining what happened may be difficult because the plane's flight data and voice recorders may be at the bottom of the ocean.

The plane sent a series of automatic messages in the space of four minutes indicating system failures and a sharp dive, specialist magazine Aviation Herald said on its website, citing Air France sources.

The messages started arriving at 0210 GMT on Monday (10:10 p.m. EDT on Sunday), indicating the automatic pilot had been disengaged, and ended at 0214 with an advisory that the cabin was at vertical speed.

The crash appears to have been sudden and brutal.

Spanish newspaper El Mundo said a transatlantic airline pilot reported seeing a flash of white light at the same time the Air France flight disappeared.

Suddenly we saw in the distance a strong, intense flash of white light that took a downward, vertical trajectory and disappeared in six seconds, the pilot of an Air Comet flight from Lima to Madrid told his company, the newspaper reported.