In post-summit comments, the President indicated that the DPRK had agreed to destroy a “missile engine testing site,” which the U.S. identified “because of the heat.”

This has brought up the question of which site does he mean?

Dave Schmerler did an excellent thread about this on twitter, but I’m nothing if not stubborn and I was already halfway through writing this, so here is my (similar) take. I also gave some comments to NPR about this question, since it is a bit of a weird one.

The DPRK has four main sites that would be very easily classified as “engine testing sites,” and two canister/ejection test sites that have been occasionally misclassified as engine test sites. There are six total main candidate sites. There is always a chance that there is an unknown site that has not been ID’d in the open source yet.

38 North recently put out an interesting analysis by Joseph Bermudez Jr. detailing the razing of a missile canister/ejection test stand, which was then picked up by other news outlets and misreported as a “missile engine test stand,” despite Bermudez being clear that missile engines were not tested from that stand. Due to the phrasing of mainstream news reports, I assess that there is a nonzero chance that the “engine test site” the President was speaking of is the Iha-Ri/Kusong Proving Grounds missile ejection stand. However, the “because of the heat” comment would be inconsistent with this site, as that implies near-infrared satellite imagery picking up burn scars. While other parts of the Iha-Ri/Kusong site have been used for mobile missile launches, the razed stand was only used for non-launch ejection tests.

Maybe all of this is splitting hairs and a staffer got their notes mixed up. These are pretty granular differences. Maybe it is actually an exciting reveal.

Arms Control Wonk is all about granular differences and exciting reveals. So let’s talk about canisters, ejection, engines, and what the six different sites look like.

Engine Test Stand Vs. Canister/Ejection Test Stand

An engine test stand is fairly straightforward. It’s a piece of static infrastructure with fancy sensors and telemetry equipment. Engineers will strap a rocket engine to it, light it off, and collect data. The important difference between this and the canister/ejection test stand is that there is actual engine ignition, where a canister/ejection test will just involve a dummy weight being thrown by pressure, with no ignition.

An engine test stand, standing and testing an engine.

A canister/ejection test stand is a stand at which a canister is placed to test the cold/mortar launch systems of a missile. A cold/mortar launch is an event in which pressurized gas or other forceful event hurls the missile several dozen feet into the air. During a real launch, the missile would ignite mid-air. At the test stand, dummy missiles are thrown out of the canister and strike the ground a few dozen feet away. They do not ignite, they do not fly, they are literally just catapulted into the ground. There should be no “heat” detected at it, so these sites are not likely candidates, but I don’t think they can be discounted due to the extensive media coverage prior to the summit.

An example of a cold or mortar launched missile. The Pukguksong-2 is thrown upwards and ignites midair instead of on the ground, like most liquid-propellant rockets.

A clearly photoshopped example of an ejection test, instead of an actual launch.

Only two DPRK missiles are cold/mortar launched: the submarine-launched Pukguksong-1 (KN-11) and the ground-based mobile Pukguksong-2. These are roughly the same missile, with some nosecone variations. As such, the only two canister/ejection test stands that have been identified so far are at the two sites associated with PGS-1 and PGS-2 testing.

Canister & Missile Ejection System Test Sites:

Each site has an expandable thumbnail of satellite and ground-truth imagery, as available. I know its not an ideal format, but there are a lot of pictures here. Don’t @ me.

Iha-Ri/Kusong

Iha-Ri/Kusong Proving Grounds

40.010576° 125.220564°

Iha-Ri/Kusong Proving Grounds are only associated with the Pukguksong-2/KN-15 solid propellant MRBM.  The stand that was reported as razed by 38 North is pictured below, and is not associated with actual engine tests, just ejection tests (and, nearby, full flight tests from mobile launchers). This site can no longer be used for ejection testing, but could be reconstructed relatively quickly.

It may be the case that the President was referring to this site, as it had made the rounds in various newspaper headlines prior to the summit. However it does not perfectly fit his description of the candidate site, which was identified “from the heat,” something the ejection test site would not have associated with it.

Destruction of this site would indicate that the PGS-2 missile canister could no longer be tested from a static position. It could still be tested from a mobile launcher (which would be risky for the launcher), rebuilt elsewhere, or rebuilt in place to accommodate a new type of canister for a new type of missile.

Sinpo

Sinpo

40.018061° 128.156634°

The Sinpo test stand is part of the larger naval base at which the PGS-1/KN-11 submarine-launched ballistic missile and the Gorae-class experimental ballistic missile submarine. Bermudez at 38 North and Ankit Panda at the Diplomat indicate that Sinpo is still somewhat active, although we have not seen significant activity in 2018. This site can still be used for ejection testing. It is a very unlikely candidate, but I’ve included it for consistency to full out the list of ejection test sites.

There also are at least two ejection barges (one operational, one under construction) for at-sea testing, but those have been excluded from this analysis.

Destruction of this site would be more significant than Iha-Ri, as it supports the more active SLBM program and the presumed Pukguksong-3 development. Sinpo’s ejection stand supports the test of missile tubes prior to barge-mounting and barge testing for SLBMs, and destruction of the site would slow the SLBM program’s development. I do not expect this to be the site in question.

Solid Motor Test Stands:

Magunpo

Magunpo

39.801523° 127.560683°

Magunpo is an old surface-to-air missile site that currently hosts the DPRK’s only identified large solid-propellant motor testing facility. It is set next to the various elements of the Hungnam chemical complex, which is the probable location of the DPRK’s solid propellant industry. It would be a prime candidate for disablement, as it is a key element in the DPRK’s ongoing solid-propellant missile program. This program is expected to produce new submarine-launched ballistic missiles and, eventually, mobile ICBMs. Dave Schmerler has covered this site at NK News and on Twitter. Joseph Bermudez has also extensively covered this site at 38 North. Even without the new missiles, most countries would be expected to regularly test their missile systems for reliability assessments and quality control for new batches of missiles.

The only reported solid propellant tests from this position were on 3/24/2016 (pictured above) and in October, 2017.

This site fits the President’s description of being visible because of “the heat.” Unlike the canister sites, Magunpo’s motor tests leave burn scares visible on near-infrared satellite imagery.

Destruction of this site, without a replacement or alternative test site, would seriously affect the reliability of current solid propellant missiles and slow/halt future solid missile programs.

I am currently leaning towards the President’s statement as meaning this site, a mistaken report of Iha-Ri/Kusong, or a previously undiscovered site.

Liquid Engine Test Stands:

 Like Magunpo, all of these sites could be visible because of “the heat.”

Sohae Satellite Launching Ground:

Test Stand near Sohae Satellite Launching Ground

39.653289° 124.714391

Sohae would be a big catch. Magunpo is the most immediately relevant to the solid propellant program, but Sohae hosts the engine tests for all the large liquid propellant missiles and space launch vehicles. Destroying this site would be a significant propaganda move and would be fairly costly to the DPRK’s space and missile programs. I don’t expect this to be the site due to its importance for existing IRBMs, ICBMs, and space launch vehicles.

Destruction of this site would reduce the reliability of and slow the development of both large, liquid propellant missile and space launch vehicles.

Taesung Machine Factory/Chamjin Missile Factory:

Taesung

38.951155° 125.570321°

Taesung/Chamjin is a missile development and testing facility. This is the site where Kim Jong Un visited the Disco Ball in front of the racks of ICBMs, and is a known R&D site. Behind Taesung is a vertical test stand which was shown-off during a state media feature on reentry vehicle technology.

Jeffrey and Dave have some solid analysis of Taesung/Chamjin’s importance in the DPRK’s missile industry.

Bermudez has extensive coverage of its development both in the KPA Journal and at 38 North, including analysis indicating a possible new solid propellant test stand.

Destruction of this site would possibly slow the development of liquid propellant systems, but would not be as impactful as the destruction of Sohae or Magunpo.

Musudan/Tonghae Satellite Launching Ground:

Tonghae Satellite Launching Ground 40.852413° 129.679666°

Tonghae is the old Sohae, basically. It used to host both missile tests, space launches, and “space launches,” but appears to either be mothballed or on cruise control for a while.

The last major open-source update on Tonghae came from 38 North in 2016, where it was assessed to be under caretaker/maintenance status. It had not expanded, construction from 2013 was still halted, and it was not actively taking part in any missile testing related activities.

I not aware of any ground-truth imagery available for the static engine test stand at Tonghae. All existing open-source references are from commercial satellite images.

Destruction of this site would largely be a goodwill gesture, as the site is not currently active and is not known to have contributed to the DPRK’s missile and space programs in the past few years.

Conclusions

It is still unclear to me which site the President was speaking about. It could be the Iha-Ri canister/ejection testing site, due to a mistake in reporting, or it could be Magunpo, due to Magunpo’s importance in a very sensitive strategic program and the relative ease in rebuilding Magunpo vs. Sohae or Taesung.

It almost certainly isn’t Sinpo, which was really just included for consistent’s sake. Sinpo hasn’t been in the news (so it couldn’t be mistakenly reported) and doesn’t have a ground-based live-fire test stand, so the DPRK doesn’t usually bring the heat there.

Sohae is vital for the space launch program, so I don’t think its going to be on the chopping block.

Taesung is an important element of the DPRK’s liquid propellant R&D program, but not so important that it couldn’t be axed. It is physically close to the rest of an R&D facility, so it would certainly be inconvenient to lose, but there are other, very inconvenient alternative test sites. It is a possible site.

Maybe solid testing is scooting down to Taesung for some reason. Maybe it is a surprise new site that has only been used a few times and hasn’t been caught by open source analysts yet. There is some weird stuff going on in Nampo, maybe the west coast is finally activating its solid propellant test site.

I’m not really sure, and I’m hoping we get more data on this weirdness soon.

If you have any ideas, hit the comment section below.