FINALLY. North Korea’s Solid ICBM: The Hwasong-18

Jeffrey Lewis 0:02

Scott, you're gonna have to edit this.

Scott LaFoy 0:03

Oh I know.

Jeffrey 0:08

You are listening to the Arms Control Wonk podcast, a podcast on arms control, disarmament, and nonproliferation. I'm Dr. Jeffrey Lewis, the founding publisher of the Arms Control Wonk blog and a professor at the Middlebury Institute of International Studies at Monterey.

Scott 0:24

I am Scott LaFoy, super producer of the Arms Control Wonk podcast and senior director for nuclear and technology security programs at Exeter Government Solutions. And today we have a third.

Dave Schmerler 0:35

I'm Dave Schmerler. I'm a senior research associate at the Center for Nonproliferation Studies in Washington, D.C. And formerly a geolocation divinity.

Jeffrey 0:43

Formerly. You lost that status to Sam Lair.

Dave 0:46

I did. That was... Where's your crown, Dave? Well, Decker... Where's your crown, Dave? Decker took it last year when you stripped it from me. Failing to geolocate... God, what was it? A CNC factory that we had one image of from like the 90s. If you remember this.

Jeffrey 1:03

Oh, I remember exactly what caused you to lose your status as a divinity. I absolutely remember the moment we took it away. Yeah. So obviously, listeners, North Korea has finally tested a solid propellant ICBM. I happen to be in the D.C. office and this is a great chance to sit down with Scott in person who I never get to see.

Scott 1:25

And Dave, who I usually only see at work in Zoom, correct? And you know, have some lousy recording quality for you. Yeah, I think really the, the big thing we want to talk about is that this solid propellant ICBM cut us, caught us all off guard, and we did not expect this in the least. Oh, completely surprised. I believe we all agreed on, on 10 years, 10 years, 10 years away, 10 years away.

And every year it was 10 years away. It's like cold fusion. So North Korea has launched the solid ICBM finally. We saw this coming from about a decade away when they started doing their solid motor tests at, what was it, Mugumpo? Mugumpo. Mugumpo, way back in the day. And now we finally have something that looks a little bit like a Minuteman knockoff, but that's a little bit because everything...

Jeffrey 2:12

Before we go through the technical aspects of this thing, can I just have an I told you so? Yes. Can I just read a thing that I wrote? All right, I wrote this in 2016. We might get North Korea to agree to only peaceful space launches. There isn't much difference, but we might seek to prevent North Korea from testing its road-mobile ICBM and stop the development of new solid-fueled missiles.

Everyone will hate this recognition, but in 10 years, I'm pretty sure I will be emailing this column around reminding people back when I said we should live with the liquid-fueled rocket program to head off the solid-fueled one. This is just a future I-told-you-so paragraph.

Scott 2:51

I'm just glad we're in person because we get to hear it here. Otherwise, he would be emailing it to us and like a distro of like 300 people. I f***ing told you so. Everyone watch your inboxes for spam. It's coming out. You told us so. This was something that... Was on their roadmap a decade ago almost. We knew this was coming and you called it repeatedly.

I'll see if I have enough space and enough characters in the episode description to hotlink all of the episodes where you did the I told you so's along the way. But we're finally here.

Jeffrey 3:22

So what is your first, I'm curious for each of you, what was your first inkling that North Korea was going to pursue a solid propellant ICBM? I mean, obviously, like what, in January 2021, Kim Jong-un said, we are going to develop a solid propellant ICBM. So at that point, it was not a shock unless you were, you know, I don't know, certain people.

But what was the first tip for you two?

Scott 3:51

I think the first hint was a road mobile ICBM at the parade. When we knew that they were doing the KNO8, it looked like a liquid fuel at the time. They did that revision, I think, in 2016 where it looked like a Volna. But having a road mobile ICBM being paraded... Never made sense as a long-term solution and i think even when we saw the liquid and even when it looked like a liquid the idea was pretty clear that if they want something mobile they will at least be trying for a solid and then when they did the the solid engine test and then when they did that poco song one tests it was pretty pretty clear where we were going with this unless they had like a you know a mogadam incident that set them back

Dave 4:37

Dave? With hindsight, it's kind of hard to look back and think when I thought they were going to do this. I think obviously when they rolled out the canistered systems during the parades, that was kind of like, okay, it's not a real missile you're seeing on TV, but North Korea doesn't parade systems that they don't intend to build or try to build.

So we would look at the K-08, which was the first road mobile ICBM that we saw on the military parades. And they kept changing the mock-up that they paraded around, but I think we all agreed that it was reflective of a real program that they were working on until it wasn't, and then they switched. And with Scott's last point about the Pukuk Song 1, North Korea's missile program is very artisanal and iterative, and when they find a system or a technology that works, they tend to stretch it to its maximum.

So we saw that with the Scud going to the monstrosity that was the Unha. Which for some reason the Japanese and Koreans are still including in their missile charts.

Jeffrey 5:32

And the Japanese, yeah, it's insane.

Dave 5:33

I don't know why they're still doing that. But back to the point, is that when they started doing the larger solid fuel systems, like that was, okay, they're going to take this and stretch this as far as they humanly can. And I think we just saw that yesterday.

Scott 5:46

It was also the first time with the Pukuk song and the motor test. Those were the first real rubber meets the roads. It's not just like, I guess with my answer, it was like, oh, the aspiration's there. But those are the two things exactly where it's like, oh, they're putting money in this. This isn't just to show off.

This isn't just a deception program. They're building something. And unless something stops them, this is where they're going with it.

Dave 6:08

Just as a note to get back to later in this conversation, we all need to talk about the infrastructure. Yeah.

Jeffrey 6:15

Where is it?

Dave 6:16

Oh. Where are they building their rockets for the SALT program? Because the SALT site at Namhung has not changed at all.

Scott 6:27

Oh, and it was never big enough for...

Dave 6:29

Right. And now we have how many different SALT fuel systems? Where are they making these things?

Jeffrey 6:33

Yeah, I... Do we want to establish a reasonable order for this podcast? No. No, I think that's... Okay, well...

Scott 6:41

Chaos. All right.

Jeffrey 6:44

Well, let me drive, because we'll come back to that. Deal. So I think it is just important to put on the table that this is a natural technical evolution that any country would make. And so I share Scott's view that the minute they started parading road mobile ICBMs, I certainly knew they would want to eventually have solid propellant road mobile ICBMs because they're just so much more flexible.

And so one thing I wanted to talk about is how we talk about the advantage of solid propellant. Because I think people shorthand it as reduced launch times. And I think that's not a bad shorthand because when your propellant is cast ahead of time, you don't have to fuel the missile. It is already fueled. Right. But you can pre-fuel liquid propellant missiles.

And we've seen the North Koreans talk about ampulization. Exactly. So it's not that you can't do it, but it's really inconvenient.

Scott 7:48

Yeah. No one likes ampulizing. Actually, that was one of the worries I had where I was like, oh, are they deviating from the solid ICBM? Because when they talked about that, they were like, oh, that's the bad thing. You don't do that when you're having a good time. But sometimes apparently you do. Sometimes you do just do both.

You do the Soviet thing of trying every approach. Which is what North Korea seems to be doing. Yeah. Throw everything at the wall and see what flies, sticks.

Jeffrey 8:15

Yeah. Okay. So that was one sign for me. Okay. Then the next sign was, I think, at least for me, it was the Pukguksong program. Because those are really large diameter submarine-launched ballistic missiles. And it's notable that... North Korea has shifted over to these little KN-23-like SLBMs, which make a lot more sense for them. And so it was always curious, like, why are you building these large diameter solid rocket motors?

And I did a little thread on Twitter about this. But I went back and looked at the history of the US program. And it turns out that there's like a little technical hump that you need to get over where if you want to make a solid propellant ICBM, you need to make a really large diameter rocket motor.

And it's about 800 millimeters. And so there's a nice paper that I found that went through the history of these programs with Viacol. In the late 50s, getting over that 800 millimeter hump required dealing with combustion instability, case bonded insulation, which I don't fully understand why that's a problem with a bigger motor, I guess more pressure maybe.

I literally don't know why, and then I just think mixing that big volume.

Scott 9:38

Consistently mixing it is the other thing, like keeping it uniform, making sure that there's not like an extra crystal of boom in the wrong place where you don't want it, you don't want cracks. It's really hard to scale that up. And they used the Tachkas for a while. We know they had the KNO2s. Which, by the way, we now know are Hwasong 11s.

Jeffrey 9:57

And so all these missiles are Hwasong 11s. The Toksa is the original, the OG Hwasong-11. And now the KN-23 is like the 11A, I think. Oh, my God. And the Shorty is the 11B. And they're all Hwasong 11s.

Scott 10:17

They're going to kill me. I hated Scud, too. And this is my worst nightmare for being a pet ant about missiles is this sort of s**t. But when you do a Tachka and a Tachka size one, you don't need the same, like you can certainly scale the science up, but there's different machines that you can essentially be using and totally different production lines when you're doing something that small and when you do things that are smaller.

And so, yeah, it's just hard to scale it up without blowing everyone up around.

Jeffrey 10:44

I'm nitpicking this because I got asked by someone when I thought North Korea could do a solid propellant ICBM test in 2020. And we wrote this really nice little write up where we looked at the Thiokol experience. And just saying like, well, if 800 millimeters is the barrier, then they jumped that barrier with the first Pukguksong launch.

And in the US experience, it was, you know, Three, four years.

Scott 11:13

Yeah.

Jeffrey 11:13

And so the feeling was, you know, they could test it basically at any time. And so I sent off my little analysis to someone working on this issue. And weirdly, I didn't get cited. And they decided it would be many, many years before North Korea tested a solid propellant ICBM. And it was like, but, but,

Dave 11:36

My thing, it's a little bit of a deviation here. I'm really interested in the testing and infrastructure that goes into what we just saw yesterday. So we finally saw this ICBM. Did they have a new ejection test stand for this? Where were they practicing that? They did ejection test stands for the cold launch system for the Pukuk Song 2.

They did it for the Pukuk Song 1. They did it for the Pukuk Song 3. These are iterative processes that you develop for your cold launch canister systems. I don't think you just roll out with a giant, massive, solid ICBM and hope your calculations are right and did it on the first time.

Scott 12:12

That's a really scary risk if they did. But yeah, the testing infrastructure has not been... Where is it?

Dave 12:19

Where is everything in North Korea's solid program and why haven't we found it?

Jeffrey 12:22

So I think that is the next thing to walk through because... We could see all these indications. They're parading the canisters. Kim Jong-un is saying he is going to do this. There's the natural technical evolution that they're on. So it's clear as a bell. And yet, until we get that test stand at SOHE, which is brand new,

Dave 12:47

They tested, how long does it take for concrete to dry? I'm fairly certain they broke a few safety practices when they tested that thing.

Jeffrey 12:56

So where is the infrastructure for the production of this missile? And OK, here's what's on my list. And Dave, you were starting to ask these questions. The places that we have identified where they cast solid rocket motors are too damn small. The ejection test stand, which could be an existing one, we just haven't seen any evidence of them using it. Maybe we missed it, right? and the engine test stand, because while they did build a new one that they showed us, I just don't think that's the only test they've ever done, and I suspect they Built that for us so they could show us pictures of it.

Right. But there must be one someplace else. So, yeah, where?

Dave 13:49

So I think, Jeffrey, we've talked about this before. We've been picking up on new construction happening down the valley northeast of Hamelin. These are berm structures. They look more closely attuned to what we'd see in Iran's missile production. So I think that's something to keep an eye on. But the thing that kind of leaves me a bit unhappy with that is that we're just watching them build this now.

So if it's incomplete, that means that there are other older sites, North Korea's solid fuel program, that we've somehow missed over the past two decades. And they were utilizing that to get to where we are today.

Jeffrey 14:26

Yeah, I do feel like there is some infrastructure that we are just missing out on. And so here are the things I have on the table. It's in the past. We have seen North Korea construct facilities so that they can show us pictures without showing us pictures of the sensitive places. Yeah, and so I think that explains the test stand. At so, hey so I think there probably must be another test stand someplace.

Maybe they're using some of that infrastructure at Magoonpo, but that seems too small to me.

Dave 15:04

Well, they did. You remember the test stand did flood and get some damage. Right. And when they rebuilt it, this is something I noticed about two weeks ago, they modified the test stand to make the base where they put the solid fuel motor longer. Okay. So you can facilitate a longer rocket at the test stand at Magoonpo.

Okay. That's just something that we pulled out a couple weeks ago.

Jeffrey 15:26

But the... Casting buildings are too small. And all of that infrastructure is on the East Coast.

Dave 15:38

Right.

Jeffrey 15:39

And they're building a port at Sohe. And so they're not going to ship solid rocket motors around the peninsula.

Scott 15:51

Right.

Jeffrey 15:53

That makes zero sense to me. And by the way, none of this infrastructure is visible at Cham Jin or San Am Don.

Dave 15:59

Right. I think the poor thing is definitely a big question. So maybe there is something to do with solid fuel on the West Coast that we've clearly missed. But going back to the test stand being at SOHE, I wonder, and this might be a good question for both of you, if that was put there because the solid fuel program wanted prestige at the National Space Launch Center.

They want a representation at the face of North Korea's kind of like scientific endeavors. So they're like, okay, we're going to build a new solid-fuel test stand, and instead of doing it where the whole solid-fuel program is, we're going to do it where the kind of like legacy liquid-fuel program, which was the face of North Korea's rocket endeavors.

It was. So maybe it's an institutional thing.

Scott 16:43

I mean, that would make sense that you kind of start stacking everything at once for a country that's also, you know, constantly kind of trying to mix its and launder its legitimacy when it comes to its space and rocketry programs. That makes a lot of sense to start putting it in the same place. It's easier. You know, you have a lot of the handling there.

You have a lot of the safety equipment there. That's interesting. It makes sense.

Jeffrey 17:06

I mean, one thing I would say is the Chemical Materials Institute got a huge expansion. I mean, a really big expansion. But we always assumed that that was just for... The motorbodies. Yeah, and nozzles and other carbon composite materials. But it's really, really big.

Dave 17:25

I agree with you. I kind of know where you're going with that, but we also don't see the berm structures for protective casting and whatnot, right?

Jeffrey 17:31

That's right. We don't. We don't. I mean, the Chemical Materials Institute had a small building that matched the bermed building at Ham Hung where they cast solid propellant rocket motors, but we never saw a big version of that. Is there just this entire parallel infrastructure that we can't see? It's all underground.

Scott 17:55

Can you imagine casting underground? First off, the smell. It's going to be bad, but like, man.

Jeffrey 18:02

Maybe not for long.

Scott 18:03

Yeah, that's one cigarette away from like a strip mining operation. You can test a rocket engine underground. I mean, you can cast underground, but God, that'd be scary.

Dave 18:14

It's probably all underground. Everything in North Korea is underground.

Scott 18:18

I mean, Really curious if they're doing the pop-up testing into the water. Not only as a way of minimizing infrastructure, but also similar to the DF-21, because I'm a broken record when it comes to my references. But when the DF-21 was still the jail, a lot of the pop-up tests were directly into the water. They were from different types of infrastructure, but you had some that were water-based.

Not all of them, but like... If you're already there... Were they doing that from the land or from, like, a vessel? I think it was a mix. I think it was mostly from a vessel, if memory serves. And then they did a drop test from a bridge, which is one of my... I love that one still. I love that video.

But I don't know a case of someone literally just, like, having a catapult and just, like, kind of eating a missile from the land into the water. There's no reason you couldn't. Yeah. ... I would be more concerned that that would be indicative of a common canister being built for the imaginary, the nuclear submarine that I'm sure they're working real hard on.

Dave 19:14

2019, five days a week, I'm looking at Shumbo. I've yet to stop, and that submarine is still not in the water.

Scott 19:23

Whenever you decide your first nuclear reactor is going to be also on a submarine, it's like, okay, Jan, good luck. Yeah.

Jeffrey 19:31

And so then there's the question of the missile design, which looks very Minuteman-ish. It's got a very large diameter first stage followed by a slender second and third stage. So that's a pretty normal looking design. We haven't had a chance to measure it yet. But it's big.

Scott 19:55

Yeah. I feel like that was the least surprising thing to me was it was just like, that's a solid ass missile. It's kind of like when they started doing the, the ones that look like Grom's and a Scander's just solids kind of look like this nozzle is going to be really interesting. Cause where, where it looks like it's a flex nozzle.

It looks like it's following kind of the American school of design there. Didn't look like it had just the world's largest graphite fins or anything hidden in it. But

Jeffrey 20:23

By the way, I really got obsessed with the question of why would you do multiple nozzles on a solid propellant missile.

Scott 20:31

Oh, that's a, yeah.

Jeffrey 20:33

Which, a thing we see with early US ICBMs, a thing we saw with early Chinese solid propellant missiles. It turns out the answer, which I like surfaced historically, is it's very inefficient. But in the era before carbon composites where you couldn't do flex nozzles, That was the easiest way to steer the missile.

Scott 20:59

Oh.

Jeffrey 20:59

So it's a suboptimal, archaic technological solution. So it is no surprise that the North Koreans did not do that.

Scott 21:08

Yeah. Well, that makes sense. It's interesting. Did you run into the fringe case of when you have multiple nozzles because you're secretly not one solid propellant missile, but you're four smaller solid propellant missiles wrapped in one body? Yeah. Because there's a lot of good videos of fail states of those because once they unwrap, they tend to just sort of – listeners can't see the hand gestures.

Jeffrey 21:28

Just sort of imagine – Just think back to 1986 where one goes one way and one goes the other.

Scott 21:34

Yeah, because that's what the – I think the RT-1 in the Soviet Union, the closest thing to like the first solid propellant one was actually four solid rockets. It's the same thing that the Hyunmoo and the Nikes –

Jeffrey 21:45

It's interesting that the North Koreans didn't feel that they needed to do that. That they just built a proper solid propellant ICBM.

Scott 21:55

Completely skipped that very inefficient but doable step.

Jeffrey 22:01

So, I don't know. I mean, it doesn't come as a surprise to us. The missile looks like it should look. It seems to perform about like it should perform.

Dave 22:09

When do you think we're going to get another one? I think that's a really good question. It's not crazy at all.

Scott 22:15

Do you mean a second test or a revised design? Oh, I mean... Yes. Okay. Fair enough.

Dave 22:20

Because we saw that with... We saw the Hwasong-12. Yeah. And then immediately after, Hwasong-14. And I'm like, that's it. That's our ICBM. And they're like, no, we're getting bigger. And then they had the Hwasong-15. And we all kind of settled down. We're like, that's their biggest... And then they came out with the 17. So are we going to see that same iterative process?

Jeffrey 22:38

So I think so. And the reason that I think so is... We have a really wonderful case here of bureaucratic politics at work, right? I mean, I have mentioned repeatedly that the only two times that Kim Jong-un seems like a warm and fuzzy dude is when there are kids in the room, his eyes light up, he loves children.

Dave 23:02

Do you think his staff are making the family come so it's easier for them?

Jeffrey 23:07

Probably.

Scott 23:08

I mean, boss is in a better mood when the family's around.

Jeffrey 23:11

I mean, say what you want about the man as an evil dictator. His father did none of that stuff. He does not have to bounce children on his knee. He, I think, feels incredibly warmly toward children. And he loves missile scientists. He gives them big, sweaty bear hugs. He gives them piggyback rides. He lavishes nice homes on them.

He is physically demonstrative with them in a way that really strikes me. And I think that means the people who are driving this program are people like Kim Jong-sik and Jang Chang-ha, who are technologists. This is not, as best I can tell... A military-driven program. I mean, the military may be happy with this. They may be unhappy.

The historical Chinese case was that the PLA hated the idea that the government was spending money on rockets and would have preferred more tanks. So I think that's why we see so much iteration, right? It's a giant freaking science project and Kim Jong-un loves it and it's funded very well and they wanna keep doing new stuff. So yeah, yeah, I think you're gonna get a series of ever bigger solid propellant ICBMs until they can put MIRVs on a solid propellant ICBM.

They're gonna just keep going. Which is the only way you end up with, what, now are we at five Poisson 11s? They just... They're not economizing because as a bureaucratic entity, you don't want to economize.

Scott 25:02

I feel like the solid ICBM, though, because they're so much more expensive... It's not like the Hwasa on 11 where you can crank out a dozen of them. I would be curious if it gets too expensive and too risky to iterate a little. I can't see them not trying. I'm really curious if they'll succeed at iterating.

Jeffrey 25:20

Right, if they'll hit some kind of technical or financial barrier.

Scott 25:23

Or a town. They'll hit something. But that's totally incidental. There's no way they're not going to try to iterate because the goal is having a peacekeeper. Once you have a Peacekeeper, there's not much... Like, after that, you're just playing with new basing modes. But having that Murr...

Jeffrey 25:41

I mean, they love basing modes. That's true, to be fair enough. I mean, are they going to stick multiple Warhead... ICBMs in the bottom of reservoirs and on trains. What's the name of the giant torch?

Dave 25:55

Are they going to drop them off aircraft? The giant torch? The Juche freedom statue thing?

Jeffrey 26:01

Oh, that thing's going to pop open like a Bic lighter and off it goes? I think they're going to have a good time. I mean, I don't know that they're going to run out of crazy things to do, at least not in the near, near future. So, yeah, Dave, I think we are. I don't know how soon we're going to see another test.

But, you know, given that in 2017 we saw the 12, 14 and 15 all in quick succession. Oh, a thing that we often talk about that we should maybe is good to close on is. We should keep in mind that these are the systems that they're choosing to display to us.

Scott 26:43

Yes.

Jeffrey 26:45

It is not the case that in 2017 they tested the 12 and then a few months later had developed and tested the 14. They had the 12, 14, and 15 all basically ready to go and they unveiled them to us. Right. And so we have been seeing now for, I don't know, five or six years Really clear indications of a solid propellant missile program.

And so I wouldn't be surprised if they have other designs in advanced states ready to be tested. So what was this? This is the Hwasong-18?

Dave 27:24

18.

Jeffrey 27:25

You know, so you might get a 19 or a 20. And I just, it's what we saw with the Pukuk song. I mean, how many freaking Pukuk songs have we seen now? Five? Five, I think. Five, four, four and a half. Five, four, four and a half.

Scott 27:39

I saw someone write PGS6 on something and I literally had to walk away and I was like, I don't know if that's real or I don't know if they miscounted or I miscounted. There's too many. It's very complicated to track these now.

Jeffrey 27:51

So what makes you think this is going to be any different? And these systems probably already exist. Yeah and it's just a matter of sitting back and waiting and while we wait getting dave to find the rest of the damn infrastructure they just need to hold another concert with a nice powerpoint slide in the back again and do the the drip drip drip and give us something that would make my day it would be i mean they have to do a concert for the contributors to the successful hua song 18 launch

Dave 28:18

Then we might get pictures from the infrastructure.

Jeffrey 28:20

And we're probably going to see some brand new scientists from the solid propellant side, which would be very exciting.

Dave 28:29

Maybe get some good music, too.

Jeffrey 28:31

And can it be long before we see this thing in Iran?

Scott 28:38

Danger. Shipping the knowledge, but shipping the parts, man.

Jeffrey 28:43

Yeah, I know. I know. I know. Maybe they just, yeah, it's only the liquids that they cooperate on. But I don't know. It's an exciting time we live in.

Scott 28:55

I remember when I was in grad school. My grad school was focused very much on coin and terrorism and everything. And I was one of that few, like, nuke and missile peoples there. I was like, oh, you know, I just really wish this program focused a little. It was a great program, but I just wish it was a little more focused on, like, missiles and nukes.

F*** Monkeys, Paul. I want to go back. I wish we were back in coin era. I wish we were back in terrorism era. I regret wanting that because we're here. We've been here a couple of years, but.

Jeffrey 29:21

You know where a great place to discuss all this stuff is, Scott? Is it the Slack channel? It is indeed the Arms Control Wonk Slack channel. So if you enjoy the random walk conversations about North Korean nuclear missiles that we are able to do here and want to consider supporting the podcast, for $3 a month if you're a student, $5 a month if you are a regular person.

Scott 29:46

Regular person is what we normally go?

Jeffrey 29:50

Although I would say we're all quite irregular. Yeah, that's probably become false advertising at this point. You can continue these random conversations in what I think is a pretty big and vibrant community. Just go to patreon.com forward slash ACW podcast.

Scott 30:09

I've operated that for years. I cannot remember. That sounds right to me, though.

Jeffrey 30:13

Okay, well, if you don't hear a re-record of this, it was right. And if you do hear a re-record of this, you will never know. Scott, Dave, thanks for coming on. Thanks for having us. Thanks for having us.