NATO will love Sweden’s Gotland-class stealth submarines
The Swedish Navy’s third and final submarine of Gotland-class is now is undergoing an extensive upgrade. The Swedish Defense Materiel Administration (FMV) had previously awarded Saab a mid-life upgrade contract (MLU) for Gotland-class submarine, HSwMS Hallandfirst put into service in July 1997
The total value of MLU The contract is approximately $ 116.75 million (SEK 1.1 billion), and as part of this upgrade project, Saab will carry out modernization and modification work on boat at its shipyard in Sweden.
The small submarines have proven to be quite capable, despite reportedly costs only a third of the Russian Kilo-class boats. Each is only 60.7 meters long when it was built and later upgraded to 62.7 meters, while the boats shift just under 1,380 tons. Maximum crew is 32 officers and sailors, and it submarines are equipped with four 533 mm torpedo tubes, two 400 mm torpedo tubes and 48 weapon mounts.
Although the submarines were designed between 1990 and 1997, each has already undergone minor modifications during its respective lifetimes. The MLU upgrade has been much more significant, during which HSwMS Gotland was actually split in two to allow for major upgrades. In addition, more than 59 new systems have been installed or heavily modified, of which 20 are new systems that will be used in the next generation in the future. Blekinge class.
The improvements will enable the boats to make an analysis of their surroundings with a so-called Optronic Mast, which replaces the traditional periscope and associated management system.
Gotland class: Sweden’s Silent Carrier Killers
The Gotland-class submarines are far from your usual diesel-electric boats. In fact, these were the first submarines in the world with one Stirling engine air-independent propulsion (AIP) system, which allows the submarines to have an extended endurance of weeks – a capability that was previously only available with nuclear-powered submarines.
This is because submarines with diesel engines usually need to come up every few days or draw in air from the snorkel to recharge their batteries. Instead of Gotlandclass, the batteries are saved at times when the submarines need speed but otherwise cross on AIP.
As a result, the boats can reach speeds of eleven knots on the surface and 20 knots under water.
The technology behind AIP mainly involves storing an oxygen supply in the submarine in order to be able to run a diesel engine underwater. And more importantly not kill the crew in the process.
In this case, liquid oxygen (LOX) is stored in tanks on board the submarine and sent to the diesel engine for combustion. That oxygen is later mixed with an inert gas such as argon and then sent to the engines. The exhaust gases are cooled and scrubbed to extract any remaining oxygen and argon, while the remaining gases are released into the sea after being mixed with seawater. The extracted argon can be mixed with oxygen and sent back into the diesel engine.
Using the AIP system on a diesel-electric submarine can significantly increase its underwater endurance, allowing it to remain submerged continuously for up to weeks without appearing. Another advantage of the AIP system is that the submarines cost much less than a nuclear-powered submarine, but remain deadly silent when cruising underwater at low speeds, even for weeks at a time.
The result is a true submarine killer.
The Swedish AIP technology proved particularly successful when the US Navy leased HSwMS Gotland (A-19) for use in anti-submarine warfare (ASW) exercises 2004. During the exercises Swedish submarine was so quiet which could actually “sink” the US Navy Nimitz-class aircraft carrier USS Ronald Reagan (CVN-76) in a simulated attack.
The result was even replicated several times, and in any case the stealthy Swedish submarine proved that it was be able to “run rings” around the then newly built aircraft carrier for 6.2 billion dollars and its strike group.
The US Navy conducted several exercises Gotland over the course of a year, and each time the submarine successfully and quietly maneuvered around destroyers and even nuclear attack submarines. American officials were so impressed (and probably even appalled) that they leased the Swedish boat for another year to understand how it went undetected so successfully.
Now with the Gotland-class boats even more greatly improved, they will be able to run rings around Russian ships in the Baltic Sea.
Now the senior editor of 1945, Peter Suciu is a Michigan-based author who has contributed to more than four dozen magazines, newspapers and websites. He writes regularly about military hardware, firearms history, cyber security and international affairs. Peter is also one Contributing author for Forbes.