Sinpo South Shipyard: Construction of a New Ballistic Missile Submarine?

New Beyond Parallel imagery (August 26, 2019) of Sinpo South Shipyard suggests circumstantial evidence of the construction of a new ballistic missile submarine and preliminary evidence indicates possible preparations for a test.

  • These images confirm North Korean media reports late last month, in the midst of multiple sets of short-range missile tests, of Kim Jong-un’s inspection of a “newly built submarine.” We believe this to be the long-expected follow-on ballistic missile submarine (SSB) to the Korean People’s Navy’s (KPN’s) existing SINPO-class experimental ballistic missile submarine (SSBA).

  • The appearance of support vessels and a crane in the imagery suggest possible preparations, based on past practice, to tow the missile test stand barge out to sea for an SLBM test flight; but there is no conclusive evidence at the moment that this is a near-term.

The construction and commissioning of a true SSB capability would represent a significant advancement of the North Korean ballistic missile and nuclear threat and complicate defense planning in the region, given the difficulties of tracking and/or pre-emptively targeting such capabilities.

  • Despite North Korea press statements that “operational deployment is near at hand,” it is more accurate to describe the SLBM existential threat as emerging rather than imminent.

  • Nevertheless, these images suggest North Korea is making real progress in developing a second leg of the nuclear triad, bringing them closer to a survivable nuclear force and lessening prospects for full denuclearization.

On July 23, 2019 North Korean media published photographs and stories concerning Kim Jong-un’s inspection of a “newly built submarine”—the long expected follow-on ballistic missile submarine (SSB) to the Korean People’s Navy’s (KPN’s) existing SINPO- class experimental ballistic missile submarine (SSBA).1 During the inspection Kim expressed “great satisfaction” with the development of the new submarine and explained that the new submarine “is an important component in national defense of our country” and that “…its operational deployment is near at hand.”2Kim’s inspection visit is believed to have taken place at the Sinpo South Shipyard, home base of the KPN’s existing SINPO-class SSBA, submersible ballistic missile test barge and submarine- launched ballistic missile (SLBM) test stand.

While many media sources have described this new submarine as an imminent threat, it is more accurate to describe it as an emerging threat. Even if launched today the submarine will have to undergo a period of fitting-out, then manufacturer’s acceptance trials, KPN acceptance trials, commissioning and finally KPN shake-down cruises before becoming truly operational. Given historical precedence with the production and deployment of the KPN ROMEO-, SANGO-and SINPO-class submarines (all significantly less complicated that a new SSB with multiple missile launch tubes) this process could take easily take more than a year depending upon issues that arise. Even if the KPN were to conduct early SLBM test from the new submarine shortly after launch the new submarine would not be truly operational for some time. Regardless, the construction and commissioning of a true SSB would represent a significant escalation of the North Korean ballistic missile threat and complicate defense planning in the region.

Sinpo South Shipyards

Satellite imagery of the Sinpo South Shipyard, and the general Sinpo-Mayang-do area, since 2015 has yet to provide conclusive evidence of the construction of the new SSB here. There is, however, substantial circumstantial evidence including,

  • Sinpo South Shipyard is one of the few North Korea shipyards capable of building submarines and is, in fact, the nation’s primary submarine shipyard having built the ROMEO-class SS, SANGO-class SSC and SINPO-class SSBA among others.3

  • The development of new infrastructure suited to support the deployment of an SSB

  • Upgrades to the shipyard’s construction capabilities

  • Movement of parts in and out of the construction halls and parts yards

  • Associated activities in the Sinpo area

While satellite imagery collected on August 26, 2019 does not show a new SSB present it does provide an update to the activities at and around the shipyard.

Secure Ship Basin

Within the Sinpo South Shipyard’s secure boat basin, the SINPO-class SSBA and submersible missile test stand barge remain berthed at essentially the same locations as they have been since January 2019. They have, however, been joined by what appears to be a 16-METER-class midget submarine (SSM) moored alongside the SINPO-class SSBA and a support vessel moored alongside the test stand barge.

Present on the dock alongside the SINPO-class SSBA are a crane and another large vehicle. A group of people are observed on the dock alongside the test stand barge.

The presence of the 16-METER-class has no significance to the SSB, however, the support vessel alongside the test stand barge is interesting because in the past such vessels have been used to tow the barge out to sea for SLBM tests. While this, and the presence of a crane on the dock and people at the test stand barge, are suggestive of preparations for a forthcoming test, there is no conclusive evidence that this will occur in the near future. It is, however, something that should continue to be monitored.

Finally, during the past year, approximately 15 davit cranes have been installed all along the dock. At other KPN submarine bases and facilities such cranes have been used to suspend netting (sometimes camouflaged) over submarines to inhibit overhead observation.

Construction Halls

 There continues to be low-level movement of parts and components into and out of the parts yards adjacent to the construction halls on the south side of the Sinpo South Shipyard. The total number of the parts and components present appears to be less then seen at the beginning of the year. During the past eight months the communications facility 100-meters west of the main construction hall has been razed.

Test Stand

While there have been minor movements at the test stand facility over the past eight months, nothing of significance is noted in the current image and the support structure is currently positioned over the test stand. There are no indications of a recent, or preparations for a new, ejection test. This test stand was built during 2012-2014 and it and the support structure were used to support both the development of the Pukguksong-1 (KN-11) SLBM and SINPO-class SSBA’s missile launch systems.

Support Area

Located on the north side of the shipyard is and approximately 25-acre area that houses three industrial railroad spur lines and a number of miscellaneous shipyard support facilities. The August 26, 2019 image shows a level of activity that is typical of what has been observed here in the past (e.g., varying amounts of coal present near the thermal plant, small number of trucks present, movement of parts and components in the parts yards, etc.), however, no rail cars are present.

New Construction/Maintenance Hall

Construction of the new construction/maintenance hall and L-shaped pier at the southern tip of the Yuktaeso-ri (Sinpo) Peninsula, that began during 2012, continues to proceed at an intermittent and slow pace. When finished, it appears that the approximately 120-meter-long main hall will be covered with earth to provide for a modest degree of protection of attack. 4 At present, construction on the main hall appear to be at a standstill, however the length of L-shaped pier has now been extended to approximately 245-meters.