Скачать или смотреть Why the Gotland-class Submarines Are Unlike Others

You've gotta hear about the Saab Gotland-class submarine!
It was designed to be super sneaky and stay hidden for a long time, especially in the tricky waters of the Baltic Sea. While most subs are either nuclear-powered or have to constantly come up for air, the Gotland-class has a cool hybrid solution.

It all comes down to its Air-Independent Propulsion or AIP system, which uses a special Stirling engine. Get this: this system lets the sub stay underwater for weeks without having to surface or stick up a snorkel. That's a massive weakness for regular diesel-electric subs! The Stirling engine is also incredibly quiet and barely vibrates, which is a huge deal for staying hidden.