As it prepares to join NATO, Sweden is passing an important milestone in strengthening its military potential. The country has left the backbone of its first submarine in more than 20 years, called HMS Blekinge, according to a press release from manufacturer Saab.

The new ships are Blekinge type submarines, 66m long, each of these submarines will have a displacement of 1,925 tons and will be powered by three diesel engines and three Stirling engines. The last of the engines uses an Air Independent Propulsion Unit (AIP) that will keep the submersible under water for more than 18 days.

The sub has a standard crew of 26 sailors, but can be modified to accommodate up to 35 sailors on board. Options are also available to further expand the submarine design to 50 sailors, but a smaller version with a floor space of 50 m and a displacement of 1,100 tons is also possible in the future.

Submarines will be AIP equipped and armed with autonomous underwater vehicles (AUVs), remotely operated vehicles (ROVs) and magnetic stirring facilities (MSFs), as well as torpedoes and mines.

The Swedes have already excelled in noise suppression technology used in submarine warfare. The flexible mounts developed on the submarine are expected to help it withstand shocks, reduce transient noise and further reduce enemy detection. The hull of the submarine will also absorb noise, and its ducts and pipes must also be quiet.

With UAV and ROV deployment options, the submarine can avoid risky missions but perform reconnaissance and surveillance missions. Drones can use active sonar to extend the range of the submarine, ready to leave the area undetected if the robotic vehicles are detected and destroyed, even if it is quietly hiding at a safe distance.

“Competence in the submarine field makes Sweden one of the few countries in the world capable of building modern and advanced submarines,” said Mikael Johansson, President and CEO of Saab. The first Blekinge-class submarine is expected to be built in 2027, followed by HMS Skåne a year later.