Activity at the Sinpo South Shipyard Part 1: The Secure Boat Basin

Key Findings

• For the past two months, a significant increase in activity has been observed at the Sinpo South Shipyard in both the secure boat basin and the construction halls.
• The observed activity does not appear to indicate imminent preparations for the launching of the much-anticipated new ballistic missile submarine (SSB) or preparations for a submarine-launched ballistic missile (SLBM) test.¹
• However, the activity is suggestive of longer-term preparations for launching the new SSB and/or testing newer, more capable SLBMs, either of which could occur by the end of 2022.
• Although the observed activity is not indicative of imminent launching or testing preparations, it should be noted that North Korea maintains the capability to undertake either of these actions on very short notice should Kim Jong-un decide to do so.

Fifteen satellite images of the Sinpo South Shipyard and its environs collected between August 11 and October 12, 2022, provide a unique opportunity to both update the status of the facility and more holistically describe the activity observed in the secure boat basin and at the construction halls during an unusually active two-month period. This report is the first of a two-part report. This first installment covers the activity at the secure boat basin, and the second discusses activity at the construction halls.

Overview

While general low-level activity is often observed at the Sinpo South Shipyard, the level of activity observed during the past two months at the secure boat basin and the construction halls is atypical and suggests something more significant.

Within the secure boat basin, the moveable opening in the canopy above the conning tower of the 8.24 Yongung (August 24th Hero) experimental ballistic missile submarine (SSBA) was open for approximately three weeks during August and September. This extended period and visible movements of the shipyard’s telescoping crane suggest work on the submarine’s sole missile launch tube in preparation for an SLBM test launch. Additionally, the repositioning of the submersible missile test stand barge five times during the studied two-month period indicates ongoing work on the barge. The activity suggests long-term preparations for testing new launch systems and conducting ejection tests for newer and more capable members of the Pukguksong family of SLBMs. Either or both of these efforts have a clear potential to be undertaken by the end of 2022.

The Secure Boat Basin

An image acquired on August 11, 2022, shows the secure boat basin with the 8.24 Yongung SSBA tied up along the dock under the approximately 102-meter-by-13-meter canopy, an infiltration mothership tied up immediately aft of the submarine, and the submersible missile test stand barge (used for ejection testing of SLBMs) and a small harbor tug tied up along the south pier.²

By August 28, the test stand barge was moved to a position along the north pier, and the moveable opening in the canopy over the 8.24 Yongung SSBA’s conning tower pulled back, revealing the top of the conning tower. This opening over the submarine’s conning tower is only known to have been open during periods of maintenance/repair work or preparations for an SLBM test.³ The telescoping crane typically associated with such activities was also observed working at the construction hall’s support pier at the time of the August 28 image.⁴ No activity is observed along the dock or piers of the secure boat basin.

Approximately two weeks later, on September 12, satellite imagery shows that the test stand barge was moved once again and tied up along the south pier. The small harbor tug appears to be tied up portside of the 8.24 Yongung, barely jutting out from under the canopy forward of the conning tower. The conning tower remains visible through the opening in the canopy over it. An image acquired the following day shows no changes to the 8.24 Yongung, infiltration mothership, or missile test stand barge. However, the small harbor tug is now tied up opposite the conning tower of the 8.24 Yongung.

While no changes in the positions of the vessels in the basin are evident, a September 18 image shows one of the clearest views through the canopy opening above the conning tower of what appears to be the hatch to the missile launch tube. Another image acquired two days later, on September 20, shows no significant movement of the vessels within the secure boat basin. Outside the basin, the telescoping crane is visible in the motor vehicle maintenance and storage facility on the north side of the shipyard.

Imagery acquired on September 24 and 26, while of only 3-meter resolution, shows that sometime between September 20 and 24, the test stand barge has once again been moved to the north pier. Three days later, on September 29, a 70-centimeter image shows that while the positions of the vessels had remained unchanged, the opening exposing the conning tower of the 8.24 Yongung has been closed. Significantly, a telescoping crane and an unidentified vehicle or piece of equipment were present adjacent to the test stand barge, albeit on the outer wall around the secure boat basin.⁵ Regardless of its position, the crane could easily reach over the wall and support work on the test stand barge. The small harbor tug is not visible in this image.

Two days later, on October 1, another 70-centimeter image shows all vessels in the positions they have occupied since September 24 and that the telescoping crane was, once again, in the motor vehicle maintenance and storage facility just north of the secure boat basin.

A little over a week later, an image collected on October 10 shows the opening over the conning tower remains closed, the small harbor tug is present and now tied up to the bow of the 8.24 Yongung, and the test stand barge has been moved forward along the north pier and closer to the dock. This image also shows the telescoping crane parked, albeit in a different location, within the motor vehicle maintenance and storage facility.

Two days later, on October 12, a 70-centimeter image shows no significant changes to the positioning of the vessels within the secure boat basin, although the small harbor tug is now tied up alongside the 8.24 Yongung. In addition, the telescoping crane is no longer present at the motor vehicle maintenance and storage facility.

Although the activity observed within the secure boat basin over the past two months are not indicative of imminent preparations for the much-anticipated launching of the new ballistic missile submarine (SSB) or SLBM testing, it should be noted that North Korea maintains the capability to undertake either of these actions on very short notice should Kim Jong-un decides to do so.