The chief investigator of Air France Flight 447 said that the world may never know the reason why the Airbus A330 crashed into the Atlantic with 228 people onboard.
Despite a fleet from the Brazilian navy continuing its search for bodies and debris, accident investigators believe the chances of recovering the black box would be virtually zero as it would be 3,000 metres under water - a depth at which no black boxes have previous been recovered. The search would be made even tougher as the ocean floor in the region is mountainous.
However a French deep-sea research vessel and robot submarine will begin their search to track and retrieve the recorders, which should be transmitting homing signals.
Even with the recorders, investigators might never be able to solve the mystery of Flight 447, said Mr Arslanian. He said: “I cannot rule out the possibility that we might end up with a finding that is relatively unsatisfactory in terms of certainty.”
Meanwhile the navy along with French spotter aircraft are scouring an area about 745 miles (1,200km) northeast of the coastal city of Recife. They have so far found seats, plastic and sections of aluminium on the surface from the Airbus A330 that came down early on Monday while flying through severe storms from Rio de Janerio to Paris. The discovery dashed hopes that passengers could have survived.
Reports of a recent bomb threat to an Air France South American flight rose speculation that an explosion could have caused the mid-air crash. However airline sources said that the company have ruled out the false alarm, which involved an aircraft at Buenos Aires airport on May 27.
Last night Nelson Jobim, the Brazilian Defence Minister, also ruled out an explosion. A large fuel slick found at the crash site “means that it is improbable that there was a fire or explosion”, he said.
Speculation continued to focus on theories that severe tropical storms were behind a terminal failure of the aircraft’s electronics. The last word from the pilots, half an hour before the crash, reported bad weather in the area. Other theories include ice having blocked the aircraft’s external air probes, confusing its computerised flight system.
President Sarkozy and Carla Bruni attended an all-faiths ecumenical service at Notre Dame cathedral in memory of the victims of the world’s worst air disaster since 2001.
Passengers included 61 French, 58 Brazilians and 26 Germans among the 33 nationalities represented.