Walrus-class

The development of this submarine class followed a 1974 naval plan to replace preceding vessel types. Research initiated in the 1960s concluded that diesel-electric propulsion was the only sustainable option, as nuclear alternatives were restricted by cost and maintenance requirements. While the design was largely finalized by 1978, the construction phase was defined by significant technical and financial instability. The bankruptcy of the primary industrial contractor and the need to modify the hull length of the initial units to accommodate finalized equipment contributed to extensive delays. A major fire in the command center of the lead vessel in 1986 resulted in the total destruction of its internal systems, forcing the transfer of components from subsequent hulls to complete the repair. These complications, characterized by significant cost overruns and delays, resulted in the second hull being commissioned as the first of its class in 1990.

These attack submarines are constructed using specialized elastic steel to facilitate deeper diving depths than previous generations. A defining technical feature is the "X" configuration of the four combined rudders and diving planes, a complex assembly designed for enhanced maneuverability. The platform relies on high levels of automation to reduce the necessary complement while maintaining operational effectiveness. Submerged stealth is a primary design priority, rendering the vessels difficult to detect by surface, aerial, or sub-surface assets. Offensive systems are centered on four torpedo tubes capable of launching heavyweight torpedoes, anti-ship missiles, and mines. Modernization efforts have integrated optronic masts for high-definition day and night imaging, mine-avoidance sonar, and updated combat management systems to support littoral operations and special forces deployment.

Initially designed for anti-submarine warfare during the Cold War, these vessels have been utilized for a broad range of intelligence-gathering and surveillance missions. Their operational history includes deployment to the North Atlantic, the Mediterranean, the Persian Gulf, and the Caribbean, often for classified intelligence purposes. The class has been employed for the enforcement of international sanctions, such as during the Yugoslav Wars, and for anti-piracy operations off the coast of Somalia. In addition to active deployments, the vessels are utilized for the Submarine Command Course, providing training for prospective commanders from multiple international navies. The class remains active in mock combat exercises and has been involved in documented operational encounters with foreign carrier battle groups in the Mediterranean.