Why Australia wants new submarines?

File photo Collins Class submarineImage copyrightGetty Images
Image captionThe new submarines will replace the aging fleet of Australia's Collins-class vessels
The government says that the existing fleet of Collins class submarine aging and needs replacement.

Strong ability submarine is seen as vital for an island nation such as Australia to conduct surveillance operations, counter the growing military power of countries such as China and support the Australian allies.

What submarines are DCNS will build?

Computer graphics of Shortfin Barracuda submarineImage copyrightDCNS Australia
Shortfin Barracuda is a 4,500-ton submarine and traditionally. It is closely related to the Barracuda nuclear-powered ship, which weighs 4,700 tons.

DCNS said full details are confidential, but the ship to know to be more than 90 meters in length and to show the improved pump-Jet Propulsion system, which should be quieter than propeller propulsion systems.

Mr Turnbull said the French proposal "represents an opportunity is best suited to meet the unique needs of Australia."

What were the other proposals

Japanese Patent Application, with a consortium led by Mitsubishi Heavy Industries Ltd, offered his version of the 4000-ton Soryu class submarine, to extend between 6-8m.

Mitsubishi stated that "deep regret that Japan's capabilities were not sufficiently conveyed."

The German application is powered by TKMS, proposed version of the current 4,000-ton 2,000 ton Type 214 class submarine.