Search teams are still assessing the Black Sea site of last week’s Armavia Airbus A320 crash in a bid to ascertain the location of the aircraft’s flight recorders and whether further assistance will be needed to retrieve them.

Russia’s emergency ministry has stated that additional equipment is necessary to pinpoint the location of the wreckage from the twin-jet which came down on 3 May while on approach to Sochi Airport.

“The radio beacon signals emitted from the bottom of the sea does not yet give cause to suggest that the flight recorders will immediately be raised,” says the ministry.

“At the moment there is a need for auxiliary equipment to determine more precise co-ordinates,” he says, adding that more than 23m3  (810ft3) of aircraft wreckage has so far been retrieved.

French air accident investigation agency Bureau d’Enquetes et d’Analyses (BEA) offered assistance in the immediate aftermath of the crash and Russia could call upon French experience gained during the Red Sea search two years ago for recorders from a crashed Flash Airlines Boeing 737.

The ministry says that the work has been complicated by the “complex” geographical relief of the sea bed and the heavy concentration of hydrogen sulphide present in the Black Sea.

Recovery work has also been hampered by an “enormous quantity” of plankton which has obscured visibility. The depth of the flight recorders has yet to be firmly established – initial ministry estimates stated that they could be up to 680m (2,230ft) down, but there is optimism that they are resting at a much shallower depth.

Some 760 personnel are involved in the recovery effort including representatives of Russia’s Institute of Oceanology and the country’s transport ministry.

Source: Flight International