Singapore formally commissioned its first two Invincible-class submarines, the RSS Invincible and RSS Impeccable, on 24 September 2024. The event, officiated by Prime Minister Lawrence Wong, marks a new stage in the Republic of Singapore Navy’s (RSN) development, 25 years after the country first acquired submarines.

The newly commissioned vessels were designed by Germany’s Thyssenkrupp Marine Systems (TKMS), with the goal of enhancing the RSN’s underwater capabilities.

These submarines are intended to replace the older, second-hand Challenger- and Archer-class submarines, which Singapore acquired from Sweden.

The new Invincible-class vessels, built to Singapore’s specifications, offer updated features such as improved maneuverability and quieter operation, while requiring a smaller crew. Prime Minister Wong noted during the ceremony that these submarines are “quieter, more durable, and better armed” than their predecessors.

The commissioning of these vessels comes as part of Singapore’s broader effort to maintain a credible defense force. Prime Minister Wong emphasized the need for the Singapore Armed Forces (SAF) to continue adapting to modern challenges, including evolving technological and strategic landscapes.

Wong highlighted the RSN’s progress from its modest origins in the 1960s to its current role in safeguarding the country’s critical sea lanes.

The new submarines are part of a 2013 order placed by Singapore with TKMS, followed by a second order in 2017. The Invincible-class, known as the Type 218SG, is tailored for operations in Southeast Asian waters, where factors such as high salinity and warm temperatures influence submarine performance.

Each submarine measures 70 meters in length, displaces 2,000 tons, and uses a diesel-electric propulsion system with air-independent propulsion (AIP), which allows for extended underwater endurance. These design features reflect the RSN’s experience in operating submarines in the region and aim to enhance operational flexibility.

Colonel Fong Chi Onn, commander of the RSN’s 7th flotilla, acknowledged that the design of the Invincible-class submarines was influenced by years of submarine operations in local waters. However, he also noted that the vessels incorporate international design standards and best practices, highlighting a mix of local requirements and global expertise.

The Ministry of Defence stated that the new submarines are equipped with more automation, which reduces crew size and extends underwater endurance by 50% compared to the older Archer-class submarines.

Other improvements include ergonomic adjustments, such as better placement of operator consoles and valves, to accommodate Singaporean crew members. The submarines have also been designed with accommodations for mixed-gender crews, in line with the navy’s shift toward integrating female personnel into various roles.

The two remaining submarines in the class, the RSS Illustrious and RSS Inimitable, were launched in December 2022 and April 2024, respectively, and are expected to be delivered to Singapore by 2028.

The acquisition of the Invincible-class submarines comes amid Singapore’s broader defense modernization efforts. The SAF is also preparing for the arrival of F-35 stealth aircraft by 2026 and plans to introduce next-generation howitzers to bolster its artillery capabilities.

During the commissioning ceremony, Wong stated that the SAF must continue to adapt to new types of warfare, including threats in cyberspace and technological advancements. He added that efforts are underway to develop autonomous systems and enhance digital defense capabilities.

In December 2021, Militaryleak.com reported that the initial deal for the first two Type 218SG submarines was valued at €1.6 billion (S$2.3 billion), which includes the cost of construction, logistics, and crew training. The RSS Invincible, the first of its class, was launched in Germany in February 2019 and began sea trials in September 2020.

The decision to invest in the new submarines reflects Singapore’s ongoing defense strategy, which focuses on updating military hardware and preparing for future security challenges. However, the introduction of these submarines also comes at a time when other regional powers are similarly upgrading their naval capabilities, raising questions about the potential for an arms race in Southeast Asia.

While the commissioning of the Invincible-class submarines is a notable step for Singapore, it is part of a broader trend of regional naval expansion. Several neighboring countries are also enhancing their submarine fleets and overall maritime defense systems, contributing to a more complex security environment in the region.

The Invincible-class submarines represent a significant technical upgrade for the RSN, but how these new assets will influence regional naval dynamics remains to be seen. For now, Singapore’s focus remains on maintaining a capable defense force able to respond to both traditional and emerging threats.