Trials of middle diesel engine have been started at Ukrainian submarine Zaporizhzhia.

Ukrainian sub Zaporizhzhia kicked off powerplant trials

According to Ukrainian defense ministry, a damage control drill was held prior to the trial; divers inspected underwater part of the sub and then trials of main electric motor started. Right diesel was tested on slow, middle, and full speed modes. 

As was reported by e-crimea, it was planned to commission submarine Zaporizhzhia in May 2011. The sub's mooring trials were conducted in December, sea trials are scheduled in May; after that the sub is expected to be commissioned. 

Since Feb 2003 Zaporizhzhia has been under repairs at 13th Ship Repair Plant in Sevastopol. Previously, Ukrainian defense ministry planned to sell the submarine right after her commission. 

Currently, Zaporizhzhia is the only Ukraine's submarine; in May 2009 the sub started post-repair trials. 

Project 641 diesel electric submarine was built in 1970 and joined Soviet Navy in 1971. In accordance with an agreement separating Soviet Black Sea Fleet, in 1997 the sub joined Ukrainian Navy and was renamed into Zaporizhzhia.