"The Falcon small-class compact remote-operated vehicle found the main flight data recorder 1,600 meters [0.99 miles] from the shore at a depth of 17 meters [55.7 feet] at 5:42 a.m. [02:42 GMT]," the ministry said.
It said that the black box will be sent to the central research institute in Lyubertsy on the southeastern outskirts of Moscow, which will be tasked with decoding the data, in the coming hours.
The Russian Defense Ministry's Tu-154 aircraft en route to Syria from Moscow crashed soon after takeoff near Russia's Black Sea resort of Sochi early on Sunday.
The plane was carrying 92 people including eight crew members, 64 musicians of the Alexandrov Ensemble, nine reporters, head of Spravedlivaya Pomoshch (Fair Aid) charity Elizaveta Glinka, and two federal civil servants.
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