The Ministry of Defence (Mindef) has signed a contract with Thyssenkrupp Marine Systems to acquire two more Invincible-class submarines, growing its fleet to six from 2034 onwards. 

The procurement of two additional submarines was previously announced by Defence Minister Dr Ng Eng Hen at the Committee of Supply 2025 debate in Parliament on March 3. 

"Four submarines are not optimal for a submarine fleet," said Dr Ng.

He explained that submarines are subjected to more rigorous and frequent maintenance cycles as they operate under intense pressure. This is in turn affects operational time.

"This is why most navies that operate submarines have more than four — Australia, Indonesia and Vietnam", added Dr Ng. 

The Republic of Singapore Navy started building four custom-made Invincible-class submarines, in Germany, in 2017. Two of the four existing submarines, the RSS Invincible and RSS Impeccable, were commissioned in September 2024 and have begun operations in Singapore waters. 

Mindef also said that trials and acceptance for the third and fourth submarines, Illustrious and Inimitable are progressing well in Germany, and they are expected to return to Singapore by 2028. 

Designed for Singapore's waters

The Invincible-class submarine is designed for operations in Singapore's shallow and tropical waters. 

Custom-built for Singapore's needs, the four submarines possess state-of-the-art capabilities, including high levels of automation, significant payload capacity, enhanced underwater endurance, and ergonomics optimised for the Asian physique. 

Each submarine is 70m long, weighs 2,000 tonnes, and requires a 28-man crew to operate. 

editor@asiaone.com

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