Fauzan Malufti for NavalNews, reported June 23, 2025 concerning PT PAL's KSOT "Autonomous Submarine" at https://www.navalnews.com/naval-news/2025/06/pt-pal-indonesia-unveils-its-latest-autonomous-submarine-design/
Pete Comment
The PT PAL "Kapal Selam Otonom (KSOT)" in Indonesian, translating to "Autonomous Submarine" concept, seems to have an unusually large beam and a very prominent sail/fin for an Autonomous underwater vehicle (AUV). Its 2.20m "breadth"/beam could probably accommodate 3 men sitting down and weapons. Could it be an AUV, manned minisub, or optionally manned?
Initially it may only have a Lithium-ion Batteries (LIBs) for propulsion and "Hotel Load" (non-propulsion needs, like sensors) for 90nm range (see Technical Specs below). A larger variant may eventually have a diesel engine and LIBs for the 6,000nm range mentioned below.
This Indonesian KSOT might have been joint developed by PT PAL, TKMS Germany? or Hanwha Ocean South Korea ? or DRASS Italy? or it may be even a smaller variant of Russia's Piranha/Losos? I estimate the KSOT midget submarine might become operational in 5 to 10 years.
Mock up or prototype? of PT PAL's KSOT alleged AUV, which may be big enough to accommodate 6 men sitting down. The Video here and above uploaded in mid October 2025 by Indian Youtube channel DD Global. The KSOT is being towed on a trailer at the Indonesian Armed Forces 80th Anniversary, October 5, 2025 in Jakarta.
Below and here see NavalNews video, uploaded June 12, 2025, featuring an interview at Indo Defense 2025, June 11-14, 2025 in Jakarta.
The video above presents many Technical Specifications for the KSOT here. Those Technical Specifications, as at June 2025, being:
"Length Over All: 15.00 m
"Length Over All: 15.00 m
Breadth [beam]: 2.20 m
Draft: 1.85 m
Deadweight: 37.28 ton
Cruising Speed: 5.00 Knots
Endurance: 18 hours (Final Spec up to 6 Months)
Maximum Speed: 8.00 Knot
Range: 90 nm (Final Spec up to 6,000 nm)
Maximum Depth: 50 m (Final Spec 350 m)
Deadweight: 37.28 ton
Cruising Speed: 5.00 Knots
Endurance: 18 hours (Final Spec up to 6 Months)
Maximum Speed: 8.00 Knot
Range: 90 nm (Final Spec up to 6,000 nm)
Maximum Depth: 50 m (Final Spec 350 m)
SHIP MISSION
* Surface Underwater & Survey
* Surveillance
* Self Destruction [Kamikaze]
* Silent Attack"
The development of the KSO suggest Indonesian submarines will be, on average, smaller, varying between the small-medium sized Nagapasa and outgoing Cakra classes, small future Scorpenes, down to the midget KSOTs.
Meanwhile Indonesia's part competitor, Australia, has much larger, hugely expensive, long term plans for LOTEd Collins (5 upgraded for what will end up to be A$2 Billion each). Then 3 to 5 large US Virginia and 3 to 5 UK SSN-AUKUS designed SSNs with a smaller proportion of Anduril Ghost Shark AUVs (similar in size and function to the KSOTs).
Happy weekend Pete,
ReplyDeleteThe Indonesians have been working on a mini sub for at least a decade, there was even a 2023 article that claimed they were building Drass minisubs at a PT Palindo in Batam, which is the source of the 2016 TKMS story.
https://quwa.org/daily-news/indonesias-pt-palindo-marine-showcases-mini-submarine-design/
https://www.italiandefencetechnologies.com/drass-galeazzi-collaborates-with-the-indonesian-shipyard-pt-republik-palindo-for-the-construction-of-midget-class-submarines/
The KSOT LUUV design first appeared in 2022, and a model matching the parade version was recently shown at a trade show
https://www.navalnews.com/naval-news/2025/06/pt-pal-indonesia-unveils-its-latest-autonomous-submarine-design/
My take on the parade version? It’s a display model, at best a prototype, as it does not have torpedo tubes, and the bow looks seamless. There are four small blow holes on each side of the ‘tower’, which if real, means that this UUV will take a few minutes to dive, which isn’t fast enough for a surveillance drone that ‘pops’ up to expose its sensor mast.
Hi Shawn at 10/12/2025 4:49 PM
ReplyDeleteYes I agreed when I wrote "Mock up or prototype?" on October 10.
The Indonesians would be crazy developing the whole mini-sub themselves. Particularly the Italians have been diver delivery vehicle up to mini-sub specialists (with a Special Forces) during and since WWII.
Also the RUSSIAN Piranha-Losos midget submarine may have been a prototype, somewhat larger than the Indonesian KSOT. See https://en.wikipedia.org/wiki/Losos-class_submarine
and my 2014 article "Suspected Russian Mini Submarine, Divers? in Swedish Waters" at https://gentleseas.blogspot.com/2014/10/suspected-russian-mini-submarine-in.html .
Given the slow dive capability you point to, the KSOTs might turn out to be very much night time, semi-submerged release of Special Forces in a dingy (or swim to shore) craft.
Cheers Pete
Hi Shawn
ReplyDeleteA belated thanks for your point about DRASS midget subs.
Inimitable H I Sutton has produced an interesting article on the DRASS subs here http://www.hisutton.com/DRASS.html
Particularly the DRASS DG160 has stats similar to the TKMS Type 200 http://www.hisutton.com/Italy-Drass-DG160-Submarine.html .
As Germany and Italy worked together on the Type 212A/Todaro class such bi-nation work on midget subs is entirely possible.
Cheers Pete