September 9, 2026: Poland, along with other NATO nations bordering the Baltic Sea, is upgrading their naval forces to block Russian access to the Baltic in wartime or other emergencies. Currently, the Baltic has become a NATO sea, with Germany, Poland, Denmark, Norway, Estonia, Latvia, Lithuania, and Sweden against Russia. A branch of the Baltic, the Gulf of Finland, provides access to Russia and the port city of St Petersburg.

Germany and Poland are the Baltic's major military powers, and both have been adding warships and submarines to their fleets. Earlier this century, Poland acquired five 435-ton Kobben-class diesel submarines from Norway, paying only a few million for their transfer. Norway delivered all four boats by 2004 after they completed their scheduled overhauls. The fifth boat, decommissioned several years earlier, was cannibalized for spare parts. Norway took the Kobben's out of service due to budget cuts and couldn't find anyone to buy them, so they donated them to Poland. The Poles eventually replaced the Kobben's with the new 1,800-ton Viking-class boats developed jointly by Norway and Sweden

The latest addition to the Polish navy is the 2,000-ton A26, the first of five Blekinge-class submarines. The first will enter service in the 2030s. The first Blekinge was supposed to enter service in 2022, but that date kept changing. First to 2034, then 2027, then the early 2030s. The last of these submarines will be delivered in 2038. Poland will receive three of these boats, while Sweden gets the other two. Greece is also a potential buyer.

These boats are 66 meters long and 6.75 meters wide, with two decks. They have two diesel-electric engines and four AIP (air-independent propulsion) units that let the submarines stay submerged for weeks. This is more than enough time for one of these subs to carry out operations in the Baltic. While these boats are quieter than most nuclear submarines and nearly as capable, it is no surprise that each Bleking costs $1.3 billion. Top speed on AIP is six kilometers per hour, while it reaches 20 kilometers per hour using diesel-electric engines. Endurance is 45 days: 18 days with AIP and the rest using diesel propulsion. Crew size is 26, but the boat can be operated with as few as 17. It also has accommodations for nine commandos.

Onboard electronics include bow and conformal sonar and high-frequency intercept sonar arrays. The ship has a mine-avoidance sonar, along with devices that can detect and map the seabed. There are several periscope devices. The most powerful one is the Optronic Surveillance Mast, which contains a thermal imager and a full-color HDTV camera that can record when necessary. There is also a laser rangefinder. Underwater drones equipped with sensors are also available, along with a larger submarine drone for commandos or other special operations. There are four 533mm and two 400mm torpedo tubes, along with only six torpedoes. There is no space for reloads.