Akula was a submarine built for the Imperial Russian Navy. Akula saw service during World War I and sank in November 1915 after hitting a naval mine.
Initially the boat was to use petrol engines but these were replaced by safer diesels. The boat's design was a single hull/ saddle tank type with a diving depth of 25 fathoms (45 meters (148 ft)).
Significant initial problems were experienced and the electric motor and propellers which needed to be replaced. Akula was the first Russian submarine able to cruise long distances. In 1912 Akula made the world's first multi-torpedo volley with five torpedoes.
She subsequently served in the Baltic Fleet during World War I making 16 patrols and unsuccessfully attacked the German coastal defense ship SMS Beowulf.
She struck a mine and sank near Hiiumaa in November 1915 on her 17th patrol. Akula lies about 30 meters (98 ft) below water. All 35 members of the crew died.