French air accident investigator BEA has released details revealing the results so far of the search for Air France flight 447, and the extent of the challenge it faces to recover the wreckage and the data recorders.

Speaking at a press conference at the BEA's headquarters at Le Bourget during the Paris air show, chief investigator Paul-Louis Arslanian and his team revealed that more floating wreckage is being recovered, but the area in which it is now being found is drifting northward and widening.

He also said that the investigation does not have any technical data about the aircraft or the flight beyond that which had already been released, insisting in the face of journalists' queries that it was not his job to answer questions that would require him to speculate. He said he regretted the extent of speculation in the global media because it is "causing confusion".

On 6 June, he says, the floating wreckage was being found in an area about 100km (55nm) south west of waypoint TASIL in mid-Atlantic, spread over an area about 50km in diameter. But two to four days later more was being discovered about 50km north-west of TASIL, and meanwhile the trail of discovered wreckage had widened to cover an area about 200km in length.

Nothing has been located on the seabed yet, says the BEA. Arslanian said the objective of the seabed search is to narrow the area in which the wreckage is likely to be found, because at present it is "very large", with the ocean depth varying from a minimum of 864m (2,830ft) at the peak of an underwater mountain, to a maximum of 4,606m in a valley.

Arslanian says the locator beacons on the flight data recorder and cockpit voice recorder should transmit for "at least 30 days", but that so far no transmissions have been picked up.

He described the resources that are being deployed in the search and recovery effort, saying they involve five countries: France, Brazil, the Netherlands, the UK and the USA. Aircraft and ships from France and Brazil, and a US aircraft, are on continual search, and use is being made of satellites for surveillance. Investigators from the BEA and the UK Air Accidents Investigation Branch are on the ships, as are consultants from Airbus and Air France.

Equipment already earmarked for deployment when it is needed include three deep-sea salvage ships, remotely operated vehicles for seabed search, and submarines. The search for locator signals is being carried out by trailing receivers on lines at different depths.

Arslanian said human remains were being recovered with care, and taken for autopsy in Brazil by Brazilian specialists operating under French legal codes of practice.

Source: Flight Daily News