Sinpo South Shipyard Update: Recent Activity

Key Findings

• A visit by a senior official or an important ceremony has either recently taken place or is about to take place at the Mayang-do Submarine Base, as indicated by the eight submarines and several other vessels, including one of Kim Jong-un’s personal yachts, seen flying maritime signal flags.
• However, no significant activity is observed indicating preparations for conducting an imminent submarine-launched ballistic missile (SLBM) or submarine launched cruise missile (SLCM) from the 8.24 Yongung (August 24th Hero) experimental ballistic missile submarine (SSBA), newly launched the No. 841 Hero Kim Kun Ok SSB, or the submersible test stand barge.
• North Korea maintains the capability and resources to conduct a static pop-up test of a new submarine launched missile system or flight test of an SLBM or SLCM on short notice and at any time of its choosing.
• The Sinpo South Shipyard and activities within it play critical roles in the development of North Korea’s SSB and SLBM capabilities.
• There is a reasonable probability that sometime during the next 12 months, for both political and practical engineering or military reasons, North Korea will expedite a missile launch from the No. 841 Hero Kim Kun Ok SSB.

Overview

Four high-resolution satellite images of the Sinpo South Shipyard and its environs collected between November 7 and 20, 2023, show recent activity within the secure boat basin, near the construction halls, elsewhere at the Sinpo South Shipyard and the Mayang-do Submarine Base.

At the Mayang-do Submarine Base, an official visit or ceremony has recently taken place or is about to occur, as indicated by the presence of submarines and several small vessels—including one of Kim Jong-un’s personal yachts—flying maritime signal flags.

At the Sinpo South Shipyard, while there has been repositioning of the submarines, submersible test stand barge, submersible missile test stand barge, and infiltration mothership, no significant activity is observed indicating preparations of an imminent submarine-launched ballistic missile (SLBM) or submarine launched cruise missile (SLCM) test. However, there is a reasonable probability that during these initial cruises, North Korea will expedite a missile launch from the No. 841 Hero Kim Kun Ok SSB sometime during the next 12 months for both political and practical reasons.

There are no significant indications of recently conducted or preparations for an imminent test at the Static Pop-up Test Stand Facility. Additionally, ongoing construction-related activity is observed at the Sinpo South Shipyard’s construction halls, Sinpo Shipyard’s graving dock, and at the L-shaped pier located at the southern tip of the Yuktaeso Peninsula.

North Korea maintains the capability to undertake an SLBM, SLCM, or static pop-up test on short notice anytime Kim Jong-un decides to do so. This capability must be kept in mind as it is likely that Kim and various missile design bureaus desire to demonstrate both ongoing progress with the development of the SLBM and SLCM programs and an operational capability for the Hero Kim Kun Ok SSB.

Mayang-do Submarine Base

At the Mayang-do Submarine Base, a visit by a senior official or important ceremony has either recently taken place or is about to take place, as indicated by the seven ROMEO Class patrol submarines (SS), two SANGO Class coastal submarine (SSC) and several other vessels—including one of Kim Jong-un’s personal yachts—seen flying maritime signal flags. The number of submarines flying flags and the fact that Kim Jong-un’s yacht is also flying flags suggest that this may be related to an inspection tour by Kim or a senior Korean People’s Navy admiral.

Secure Boat Basin

The images of the secure boat basin show that it is now the home port to the 8.24 Yongung SSBA, Hero Kim Kun Ok SSB, and an infiltration mothership. Last September, the submersible missile test stand barge previously berthed here was moved to the small fishing station with a protected harbor 500 meters south of the larger construction hall in preparation for the launch of the Hero Kim Kun Ok.

Currently, the 8.24 Yongung is berthed along the basin’s south pier, the infiltration mothership along the north pier, and the Hero Kim Kun Ok is berthed under the security canopy formerly occupied by the 8.24 Yongung. The top center of the conning tower of the 8.24 Yongung, where the submarine’s single launch tube is located, is covered with a tarp to prevent observation. The section of the security canopy directly above the Hero Kim Kun Ok’s conning tower has been opened, revealing its top. A small vessel with an unusual silhouette is seen moored aft of the Hero Kim Kun Ok. Another small vessel is tied up on the portside of the submarine. Finally, a telescoping crane was present dockside of the Hero Kim Kun Ok on November 7 and appears to be just barely visible in the shadows in the November 20image. In the past, similar cranes have been observed working alongside the 8.24 Yongung SSBA, undertaking fitting out, maintenance and repair activities, and assisting with preparations for missile flight tests. Whether this crane is to present to assist with the fitting out of the recently launched submarine, positioning the security canopy, or something different is unclear.

For the foreseeable future, the Hero Kim Kun Ok will most likely remain berthed within the secure boat basin to complete fitting-out and manufacturer’s trials to validate the converted submarine’s design, provide practical experience to the builders, further refine the process of converting a ROMEO SS into an SSB. This will include Korean People’s Navy (KPN) acceptance trials and shake-down cruises.

Construction Halls

To the south of the secure boat basin, in the November 7image, what appears to be preparations for dredging along the launching ways of the larger construction hall are underway, as indicated by the presence of two crane barges and two hopper barges. Along these barges are a small patrol boat and an even smaller unidentified vessel. Barges undertaking dredging operations alongside and at the end of these launching ways have been observed on several occasions since the ways were completed in 2015. Sometime between November 7 and 20, one of the hopper barges departed and the submersible missile test stand barge, previously berthed in the small fishing harbor immediately to the south, has taken its place.

Support Pier and Small Fishing Harbor

Located immediately south of the construction halls are the support pier and a small fishing harbor to the south. Although the shipyard’s floating dry dock is observed berthed at the support pier, it, along with the submersible missile test stand barge, was moved to the small fishing harbor for the launching of the No. 841 Hero Kim Kun Ok SSB on September 6, 2023. The floating dry dock was subsequently moved back to its current position alongside the support pier; however, the submersible missile test stand remained here until sometime between November 7and 20, when it was moved to the launching ways of the larger construction hall.

Elsewhere at the Sinpo South Shipyard

No activity of significance is observed at the Static Pop-up Test Stand Facility located approximately 650-meters south-southwest of the larger construction hall. It appears to be well-maintained and is likely in caretaker status.

Construction activity at the L-shaped pier and new seawall located at the southern tip of the Yuktaeso Peninsula continues slowly with a crane barge, hopper barge, and small support vessels present. Current work appears to be the gradual placement of concrete caissons along the pier and supporting the construction of a new seawall along the shore to the north.

Sinpo Shipyard’s Graving Dock

Located northeast of the Sinpo South Shipyard is the Sinpo Shipyards graving dock. It is one of the largest graving docks in North Korea. Since its completion, it has primarily maintained the Sinpo fishery stations fishing vessels. At times, it has supported the work of the Mayang-do Navy Shipyard by undertaking the overhaul of ROMEO Class patrol submarines (SS) and, on two occasions, maintenance, and repair work on the 8.24 Yongung. It has been gradually overhauling two ROMEO Class SS for the past several months.