06/14/2026
Navigating the Deep: An Analysis of the Canadian Patrol Submarine Project
https://www.realcleardefense.com/articles/2026/06/09/navigating_the_deep_an_analysis_of_the_canadian_patrol_submarine_project_cpsp_1187505.html
Comments from a former submariner: The article is factually incorrect. Hanwha Ocean, the South Korean prime, is offering exactly what Canada has specifically asked for: the KSS III Batch 2 with no changes. Note that the first Batch 2 submarine was launched last year, with two more currently under construction. Assuming South Korea is selected as the preferred partner for the Canadian Patrol Submarine Project (CPSP), Canada would then undertake contract negotiation with Hanwha Ocean. Will there be changes resulting from contract negotiation? Quite possibly, but certainly not a major design change and certainly not a smaller submarine. Canada wants the submarine as soon as possible and, as the author correctly points out, the KSS III is an in-service and in-production submarine. Hence the reason the Koreans can guarantee a six year delivery from contract award.
The Hanwha Ocean KSS III Batch 2 has a dived displacement of 4000 tons. Note there is a difference reporting dived versus surfaced displacement which can cause confusion. In quoting submarine size, dived displacement is the metric commonly used, but it is not universal. For example, the Victoria-class submarines (née Upholder) were originally marketed as the UK Type 2400 as the dived displacement of the submarine is 2400 tons. Interestingly, the Germans and Japanese tend to use surface displacement (the double-hull Japanese Taigei-class is referred to in internal documents as '3000 tonne submarine' but has a dived displacement of >4000 tonnes). The reason being that the difference between surfaced and dived displacement is what is in the ballast tanks – which is displacement that does not directly contribute to usable operational capability. Double-hull submarine designs complicate this even further as the fuel is external to the pressure hull. It’s hard to compare apples to apples, but for KSS III versus Type 212CD it’s pretty straightforward, as both are single hull submarines with a similar reserve of buoyancy. The Type 212CD is circa 2,600 tons surfaced, 2,900 tons dived and KSS III is 3,600 tons surfaced, 4,000 tons dived with a 9.6m diameter pressure hull, so it’s 25-30% bigger by any reasonable measure. To put the size of the KSS III Batch 2 into perspective, it is exactly the same size as a Cold War US Navy 637 (Permit/Sturgeon) nuclear-powered submarine - the Americans made 51 of these workhorse submarines and they were the submarines that conducted all the Arctic operations until the later 688i (improved Los Angeles-class) submarines entered service.
With respect to the comment on jetty size, I note the slightly smaller KSS III Batch 1 looked mighty good alongside B Jetty in Esquimalt (with a South Korean frigate astern) two weeks ago. Dedicated submarine support infrastructure on both coasts is to be built as part of CPSP; it will not piggyback on existing infrastructure.
The $80 billion Canadian Patrol Submarine Project (CPSP) represents one of the most consequential defense procurement decisions in modern Canadian history. Driven by the impending retirement of the Ro
