Troubled Russian sub starts sea trials after repairs

30.07.2010 A Russian Black Sea Fleet submarine that malfunctioned last year has started sea trials after major repairs, a source at the Novorossiisk naval base said on Thursday.

In November 2009, the Alrosa diesel-electric submarine sent a distress signal and was towed to port following engine malfunction during sea drills.

The naval official said when the trials were complete the submarine would go under its own steam to its permanent location in Ukraine's Sevastopol.

The Alrosa (originally Varshavyanka), a Kilo-class Project 877 diesel submarine, entered service in December 1990. It was renamed Alrosa in 2004 after it was "adopted" by Russia's largest diamond company of the same name.

The Alrosa is the only submarine in active service with the Black Sea Fleet. It is based at a Russian naval base in Sevastopol on Ukraine's Crimean Peninsula.