Indonesia’s state-owned shipbuilder, PT PAL Indonesia, presented the model of an unmanned autonomous submarine that it is currently developing for the Indonesian Navy (TNI AL) during Indodefence 2025.
According to PT PAL’s General Manager for Design, Chabibi Nur Tahlil, the autonomous submarine, dubbed Kapal Selam Otonom (KSOT)—adopting the Indonesian term for “autonomous submarine”—is developed in response to operational requirements set by the Indonesian Ministry of Defence and Navy.
The KSOT will be produced in three distinct configurations: surveillance, one way attack (OWA or kamikaze-style), and torpedo-launch variants. The torpedo variant will be capable of carrying two heavyweight torpedoes. Chabibi added that the submarines are intended to be produced in large numbers and will be controlled through satellite and/or radio communication links.
The submarine weighs 37.28 tons and features an overall length of 15 meters, a breadth of 2.2 meters, and a draught of 1.85 meters. It is capable of cruising at 5 knots and reaching a maximum speed of 8 knots. Once fully developed, the KSOT is set to have an operational range of up to 6,000 nautical miles and can dive to depths of 350 meters. With an endurance of up to six months, it can be used for long-duration missions and integrates an onboard artificial intelligence system.
The KSOT design displayed during this year’s Indo Defence shows a substantial departure from the original concept first revealed in 2022. The new design features a more compact and streamlined hull, along with a mast system.
This marks a sharp contrast with the initial design from 2022, which was significantly larger, measuring 25 meters in length and having a displacement range of 228 to 262 tons. The earlier version was also specified with a higher maximum speed of 12 knots.
PT PAL stated that given the complexity of the project, the company is working with undisclosed partner(s). Despite this, the company claims the KSOT maintains a domestic content level of over 50%. sea trials are expected to begin in the coming months.
For the record, when the project was first introduced to the public during Indo Defence 2022, PT PAL stated that it was developing the platform with support from the German defense firm Diehl Defence, particularly in relation to its armament systems. The collaboration also includes plans for the joint production of underwater or submarine-launched missiles.
