Turkey shot down the Russian Su-24 bomber at the border with Syria on November 24, saying it violated its airspace for 17 seconds despite repeated warnings. Russia insists the plane never entered Turkish airspace.
Lt-Gen Sergei Bainetov, a deputy head of the Russian military's flight safety service, said today an inspection of the recorder has revealed that 13 of 16 microchips on its data board are nearly ruined and the remaining three are damaged.
The plane's downing has badly strained ties between Russia and Turkey.