Lets Talk about the Munitions of the KSS-III
Korean media has given us a very rare look at several munitions currently being used onboard the KSS-III.
It isn’t every day that we get to see the catalog of munitions available to the KSS-III. While the Koreans are happy to tell you just about everything you could ever want to know about the submarine itself, they understandably avoid going too in-depth into the various missiles and munitions that the KSS-III uses.
This isn’t shocking if you understand that quite a few of these munitions are viewed as “strategic weapons” that they would rather avoid discussing in detail.
These form a critical component of Korea’s “Three-Axis” retaliation strategy, part of which involves establishing a kill chain to preemptively strike strategic targets in North Korea as part of a punishment-and-retaliation approach.
The KSS-III is the key maritime component of that kill chain, able to covertly strike North Korean targets while remaining safe from the threat of land-based fires and ballistic missiles.
So, obviously, they aren’t very keen to parade these assets around for all to see. That doesn’t mean they never show them off, but they are highly selective about when they do.
The launch of the ROKS Jang Yeong-sil (SS-087), the first of the Batch II submarines, feels like an opportune time to showcase some of the capabilities that the class brings to the table.
It’s been a long while since I’ve spoken about the munitions available to the KSS-III, and I do get a lot of questions about the topic. So why not take some time to highlight what kind of capabilities the KSS-III is actually packing?
This will be a slightly different format, but I’m testing it out to see if you guys like it. We’ll be going through each in a sort of “brochure” format.
This should hopefully clear up some of the immediate confusion people have. I think doing a quick rundown will be useful—not going into every detail and history, but providing a concise overview of the basics.
Name: Hyunmoo IV-4
Class: Submarine-launched Ballistic Missile
Range: 500-800 Kilometers (sources vary)
Warhead: 1 ton
The primary armament for the KSS-III's Vertical Launch System is the Hyunmoo-IV-4, which forms the core of the KSS-III kill chain. It is designed to penetrate mountains and underground facilities that would house key North Korean leadership and strategic assets.
An absolute monster of a missile, the exact range of the Hyunmoo-IV-4 varies from 270 nm to upwards of 500 nm (about 500 km to 800 km, respectively). I have yet to be given a clear answer, but I plan toward it being closer to the 800 km area.
The KSS-III Batch II increases the VLS count from six to ten cells compared to the earlier Batch I. That's ten Hyunmoo-IV-4s, each carrying a one-ton warhead. That is explosive power equivalent to a GBU-43/B (MOAB), slightly higher in terms of pure weight.
That is a monstrous amount of firepower to be carrying at any given time, especially considering that each KSS-III will also have tube-launched cruise missiles available.
It fits with the Korean idea of maximum punishment, although in reality the primary concern here is targeting the numerous underground facilities that North Korea uses to host key personnel and store its vast quantities of ballistic missiles, some of which are estimated to be upwards of 300 meters below ground or more.
As we've seen with this year's strikes on key Iranian nuclear facilities at Natanz and Fordow, these kinds of targets can be extremely difficult to destroy with conventional weapons. To maximize the chances of destroying these facilities, South Korea has turned to ground-penetrating ballistic missiles like the Hyunmoo-IV-4 over air-based delivery platforms.
Of course, this capability could also be a negative when it comes to cost-per-ship/platform. While no one will argue the usefulness of such a capability, it's also a very niche one to have—driven specifically by the situation South Korea faces with the North.
If it isn't worth the cost or effort to acquire the Hyunmoo-IV-4 because you don't envision this need, then you essentially remove the value of the VLS, which is by far one of the major selling points of the KSS-III.
However, there is also the argument of futureproofing, which is by far the best thing about having a VLS. It's there, it's available, and if you ever do end up needing it you're going to be really glad you have it. It's not something you can just add later, either.
Cost–benefit and such: it's something one has to think about. You pay the price, but you have that capability available to you if needed, and the deterrent that comes with it.
Name: Haeseong-III
Class: Submarine-launched Cruise Missile
Range: 1,500 Kilometers
Top Speed: reportedly 830 m/s
Complementing the Hyunmoo-IV-4 is the Haeseong-III SLCM. Based on the Hyunmoo-III family of cruise missiles, the Haeseong-III is designed to provide the KSS-III with a long-range, precision-fires capability against land targets.
The Haeseong-III is equipped with a turbojet engine capable of supersonic speeds up to 830 m/s. It has a claimed range of upwards of 1,500 km and a circular error probable (CEP) of 1–3 m. It features a 450 kg warhead similar to the American Tomahawk.
The Haeseong-III is designed primarily to be launched from the torpedo tube, like the now-defunct Tubehawk. It has previously demonstrated this capability not only on the KSS-III but also on ROKN Type 214 submarines.
That is not to say it could not be fired from the VLS in the future; however, it is primarily intended to be tube-launched as a complement to the Hyunmoo-IV-4 to ensure maximum VLS space can be dedicated to the IV-4.
Name: Haeseong-IV
Class: Submarine-launched, Anti-Ship Cruise Missile
Range: Upwards of 500km, maybe
Top Speed: Reportedly up to Mach 3
The most mysterious of the options and, until now, a rarely discussed missile available to the KSS-III. We didn’t even have an official designation until now.
If you listened to my interview with Hanwha Ocean’s Head of Naval Ship International Business, Steve Jeong, and Hanwha Global Defence CEO, Michael Coulter, you would have heard this missile referenced!
What is the Haeseong-V? We don’t officially know. We can, however, make a good guess and say that this is the famed Korean anti-ship cruise missile that has been lurking in the background over the last few years.
For those who don’t know, the Koreans have had an anti-ship cruise missile available for the KSS-III for some time now. The origins of this missile are actually very interesting.
Unofficially the missile is based off of the Russian P-800 Oniks. It isn't a copy, however it takes a lot of elements and technologies from the Oniks. For those that don't know, South Korea and Russia actually have a fairly interesting history of arms exports.
The Russian–Korean arms trade is one of the more unconventional relationships to emerge from the post–Cold War years. When the Soviet Union collapsed, Moscow owed Seoul roughly $1.5 billion in unpaid loans. Rather than repay in cash, Russia offered to settle the debt through weapons, an arrangement known as Operation Brown Bear.
Through the late 1990s and early 2000s, South Korea quietly received T-80U main battle tanks, BMP-3 infantry fighting vehicles, Metis-M anti-tank missiles, and Igla MANPADS, along with a handful of Kamov Ka-32 helicopters and Tsaplya-class hovercraft.
It was a strange pairing but the deal jump-started a fairly active relationship of cooperation between Korean engineers and Russian design bureaus.
That exchange soon evolved into something deeper: technology transfer. Russian firms such as Almaz-Antey and Fakel began providing radar and missile expertise to the Agency for Defense Development, the result being the Cheongung (KM-SAM) surface-to-air missile.
Though domestically branded, the system’s core, its phased-array radar and the missile’s guidance profile, trace directly back to Russia’s S-350 and S-400 programs. Seoul even considered acquiring the S-300 in the late nineties, though opted for Patriot instead.
Similarly, the Shin-Gung MANPAD drew heavily from the Russian Igla. For South Korea, this cooperation was invaluable, providing a technological bridge from imported hardware to indigenous production. This in turn has helping accelerate the Korean transition from primarily rrlying on license-produced and foreign systems to an Independent designer of defence equipment.
By the late 2000s, however, the partnership waned. Growing relations with the North, interoperability concerns, and later the Ukraine crisis all froze direct defense trade with Moscow. Officially there were never any transfers regarding the P-800 Oniks, like many things that came out of Brown Bear.
We don't know much about the Haeseong-IV. We have lots of rumors and supposed leaks. The missile is smaller than the Oniks, with a range of anywhere from 300 km up to 500 km.
It is a supersonic anti-ship cruise missile powered by a ramjet engine combined with a solid-fuel booster, as with many similar designs. The missile is rumored to have a top speed of roughly Mach 3.
Picturing it with a ULS-07K cell would seemingly confirm that the Haeseong-V is able to be launched from the cell; however, I have only known it to be tube-launched from those I talk with.
Again, a lot of this is rumor. We don't know a whole lot about this one, and what we do know is primarily speculation. We do have a designation now, which is nice, and we know that the Koreans are offering it as a potential option for us.
Having a sub-launched, supersonic anti-ship missile available to the Canadian patrol submarine is honestly far more interesting to me than the prospect of an SLBM. That is a very scary prospect, one that for us would be a true deterrent of value.
Adding on the prospect of a single Canadian patrol submarine carrying up to ten in the VLS? That is absolutely nasty to think about. I should also note that these reportedly have a land-attack capability, though with the Haeseong-III already available I don't see much prospect for us there.
Other Potential/future missile options
Along with those mentioned above several more prospects exist as options for the Royal Canadian Navy to choose from if it desires.
The KSS-III Batch II uses a version of Babcocks Weapons Handling System. This same system is also found on the Royal Navy's Astute-class, the future Dreadnought-class, and the Spanish Navy's Isaac Peral-class. Other versions are found on the Australian Collins-class and even our own Victoria-class!
The Koreans have been keen to advertise the flexibility the KSS-III Batch II provides to export customers looking to integrate their own weapons systems.
They themselves, along with everything mentioned above, continue to use tube-launched Harpoons in an anti-ship role. Some people report that the KSS-III uses a version of the C-Star anti-ship missile; however, these are false. The confusion comes from the Haeseong-III also using a similar name.
Similarly, the future sub-launched Joint Strike Missile, currently being developed by Kongsberg with the Spanish Navy, is another potential option for a future anti-ship missile. The Germans and Norwegians are also investigating this option for the Type-212CD.
The Koreans are also working on their own subsurface-to-air missile similar to the German IDAS. This was confirmed by Mr. Jeong during his interview with us last month. I am, however, highly skeptical about these concepts.
IDAS has been stuck in development hell for almost two decades. While progress is moving forward, I remain hesitant to trust the reliability of a submarine-launched anti-air missile, even if it is intended as a last-resort, hail-Mary option.
It could be a potential future option for us, though, if we desired the capability. We don't have any actual information on what this will look like yet.
Torpedoes and Other Munitions
Moving on from missiles, we cap off this list with the torpedoes and the various other options available to the KSS-III.
The primary armament of the KSS-III is the Tiger Shark (Heavyweight Torpedo-II), a 533 mm heavyweight torpedo developed by LIG Nex1 to replace the previous White Shark torpedo.
It uses a fibre-optic/wire guidance link with an inertial navigation system for mid-course updates and switches to active/passive acoustic homing in the terminal phase.
The seeker employs conformal transducer arrays with wide horizontal coverage and includes wake-homing capability to prosecute surface ships and defeat evasive maneuvers.
Propulsion is electric, driven by a brushless DC motor powered by high-energy lithium-ion batteries to reduce acoustic signature.
Published performance figures indicate a length of roughly 6.5 m and a mass of around 1.6 tonnes, with a design range on the order of ~50 km. Top speed is claimed to exceed 55 knots.
The Canadian Navy wants an off-the-shelf solution for the CPS. Officials I’ve spoken to have indicated they are very open to acquiring a new torpedo along with the CPS.
The Mark 48 is a fine torpedo; however, we don’t have nearly enough to say it’s worth keeping. The production line has been facing issues, and the general attitude I hear is that there are likely better options that could, potentially, be manufactured here.
Hanwha has been very open with me that Canada would have the ability to select whatever torpedo it wishes, and they would be able to accommodate that thanks to the flexibility of Babcock’s Weapons Handling System and the Naval Shield Integrated Combat Management System.
Other options on the table could include Spearfish, DM2A4, or Black Shark if we desired them. That choice would be up to us. Obviously Tiger Shark would be the easiest to procure, but it isn’t a foregone conclusion.
Beyond torpedoes, the KSS-III also has the very cool self-propelled mobile mine available. The Sub-Launched Mobile Mine (SLMM) is a torpedo-like, electrically propelled seabed/area-denial weapon launched covertly from tubes or specialized handling systems.
It transits under its own power to a pre-programmed site, uses inertial navigation with waypoint updates (and GNSS when safe) to emplace itself, then switches to influence sensing—magnetic, seismic, and pressure fusion—or pattern-based detection to discriminate targets before detonating or acting as a bottom/semimoored mine.
For the older crowd, it is similar to the old MK-67 mobile mines of yesteryear; I’m not sure if those are still around. The SLMM gives the KSS-III an area-denial capability, able to covertly target adversary port facilities or block key chokepoints.
Mobile decoys, designed to emulate the acoustic characteristics of the host submarine to redirect adversary torpedoes, were also shown off at the launch ceremony.
The KSS-III is not a Wolf, it's a Tiger.
The KSS-III is designed to put mass, variety, and reach into a single, survivable hull. Its true strength is not a single weapon but the marriage of payload flexibility—torpedoes, self-propelled mobile mines, ballistic missiles, cruise missiles—that almost no other diesel-electric submarine on the market can offer.
That modularity buys operational choices, yet the same national instinct that drives Seoul to squeeze every edge from the KSS-III can be a liability for CPSP. The KSS-III is a product of its environment, and maybe that aligns with what we want.
However, such a unique design can push a platform into the realm of being too unique to align with our doctrine and needs. It is something that the people at Hanwha have to sell to us, to sell us on the use and feasibility of having such unique capabilities.
That's a question that only those at the top can answer. The KSS-III is the most versatile, modular option available to us. It provides the maximum amount of offensive capability possible for a diesel-electric submarine.
It does so by sacrificing elsewhere. It does not have the stealth that the Type-212CD, for example, offers. That is a wolf—a silent predator hunting and lurking in the darkness.
It is a showcase of different philosophies, one we will talk more about in a detailed comparison soon.
The KSS-III’s family of munitions is a statement of intent—intense, adaptable, and uncompromising—but it only balances when lethality is matched by doctrine, sustainment, and clear intent. Absent those, the boat’s greatest asset to the competition—choice—becomes its greatest danger.
Noah, thanks for lifting the curtain on the various S korean ksIII weapons. Fascinating choices there.
Excellent article Noah! I am somewhat confused though. If we get the KSS-III are we committed to the Hyunmoo IV-4? I must admit, when I first learned of the VLS on the KSS-III I was thinking of something more like the 688 class with their vertical launch tubes for the Tomahawk. I don't think we need an SLBM but I love the flexibility that a VLS could give us.