Invincible-class submarine

The Invincible class (also known as Type 218SG) is a submarine class ordered by the Republic of Singapore Navy from ThyssenKrupp Marine Systems. These submarines, along with the previously acquired Archer-class, will replace Singapore's Challenger-class submarines.

Design
The customised design is oceangoing and larger than the Challenger-class and Archer-class submarines operated by the Singapore Navy. The design is expected to be influenced by the export Type 214 submarine or Type 216 submarine, which have been designed for the potential needs of several other navies (Australian, Canadian and Indian). Features will include AIP and a combat system designed by both Atlas Elektronik and ST Electronics. The Invincible class also features an "X" rudder "which offers enhanced manoeuvrability in confined littoral waters, as opposed to the Type 214's cruciform rudder arrangement."

Competitors
DCNS competed to supply 3 submarines to the Singapore Navy for $1.8 billion.

Orders
The initial deal for two submarines was valued at €1.6 billion, including logistics and crew training.

On 16 May 2017, Singapore defence minister Ng Eng Hen announced an order of 2 more Type 218SG submarines for a total of 4. The first 2 will be delivered in 2021 and 2022, while the remaining 2 will be delivered from 2024.

The first Type 218SG submarine, named RSS Invincible, was officially launched during a ceremony in Kiel on 18 February 2019.