The 'Minehunter' Feared by North Korea... Stealth-Class Air Defense Capability

[Monthly Defense Times Editor-in-Chief An Seung-beom] Mine warfare vessels are support ships that do not receive much attention compared to the main combat ships such as KD-class destroyers, submarines, and Incheon and Daegu-class frigates.

Including one Wonsan-class minelayer, various mine warfare and minesweeping ships owned by the Navy are operated under squadrons subordinate to the Navy's 5th Component Flotilla, which integrates the operation of support vessels.

This flotilla is divided into three squadrons (52nd, 53rd, and 55th) according to the missions of the support ships. The 52nd Squadron possesses mine warfare and minesweeping forces owned by the Navy, including one Wonsan-class minelayer and nine minesweeping vessels. The new Nampo-class minelayer is also assigned to the 52nd Component Squadron. This unit is the only minesweeping squadron in the Republic of Korea Navy.

The Wonsan-class minelayer, built in the 1990s, has almost no role during peacetime and conducts few training exercises, so it has been largely overlooked despite its strategic importance, with only one ship constructed. In 2015, one Nampo-class ship was built as its successor.

This contrasts with the Swedish Navy, which has built several minelayers and assigned them various missions such as overseas dispatch and long-range patrols.

Although minelayers are thus undervalued, neighboring countries and North Korea closely monitor the Wonsan-class minelayer as a maritime force that could be operated aggressively in times of emergency. In fact, during the 1990s, the Japan Maritime Self-Defense Force reportedly paid little attention to the phased acquisition of the Korean Navy’s KDX-class destroyers but regarded the Wonsan-class minelayer and Jang Bogo-class submarines as threatening forces, as reported by the media.

The mine laying system of the latest Nampo-class minelayer is integrated and controlled by the mine command and control console in the combat information center. This system is integrated with the mine laying operation system consoles, which transmit data such as the serial codes of mines to be deployed, deployment timing, order, and coordinates from the port-side mine laying control console and starboard-side mine laying console. The port and starboard final mine laying control systems, which receive this data, deploy the mines they manage according to the mission.

Although the Nampo-class minelayer is not a combat ship, it is designed with stealth features and a high level of air defense capability because, unlike submarines, it must enter operational waters exposing its hull to enemy sensors to lay mines for enemy naval operations and activities.

It is equipped with the Korean-type air defense missile system SAAM, the same as the Daegu-class frigate, providing strong ship air defense capability. The electronic warfare system is the Sonata ECM system, which is also integrated into KDX-class destroyers. This system receives RF signals over a wide frequency range from the C band, which is a lower frequency band than the L band, up to the Ku band, enabling precise radar detection through phased array reception and digital signal processing techniques. The electronic warfare ECM covers relatively high-frequency bands from the H band to the Ku band and applies an RF lens (Rotman lens) for multiple phase modulation, offering excellent jamming signal gain, long-range response to multiple signal sources, rapid response to frequency hopping, and signal evasion capabilities.

The air defense radar integrates the SPS-550K 3D radar and SPS-540K tracking radar, responsible for detecting, tracking, and engaging air targets.

The SPS-550K radar is an S-band (E/F band) phased array radar that secures long detection ranges by halving the antenna rotation rate in modes for long-range search and detection of stealth targets with low radar cross-section (RCS), thereby increasing the line density of reflected target signals. Although it is an S-band radar, it has better angular resolution than G-band radars.