Sinpho South Shipyard: The SINPO-Class Submarine Moved to Drydock

Commercial satellite imagery of North Korea’s Sinpho South Shipyard from June 10 indicates the SINPO-class ballistic missile submarine (SSB) has been moved into the drydock. The purpose is unclear, but may be related to routine hull maintenance, minor repairs, or some kind of modification.

The SINPO-class SSB is normally berthed in the secure boat basin beneath an awning, which largely conceals the submarine’s presence. A small support vessel is typically seen in the open, at the submarine’s stern, and the submersible missile test barge berthed at the north wall of the basin. While the SINPO-class SSB was not visible on June 7, some churn in the water was observed to the south side of the covering, suggesting small craft movement.

Figure 1a. Water churn at the secure boat basin on imagery from June 7, 2023. Image © 2023 Planet Labs, PBC cc-by-nc-sa 4.0. For media licensing options, please contact [email protected]; Figure 1b. Secure boat basin on imagery from June 10, 2023. Image © 2023 Planet Labs, PBC cc-by-nc-sa 4.0. For media licensing options, please contact [email protected].

On June 10, the small support vessel associated with the SINPO-class SSB had been moved to the north basin wall, ahead of the submersible barge, which had been moved farther from the quay.

Figure 2a. Empty drydock on imagery from June 7, 2023. Image © 2023 Planet Labs, PBC cc-by-nc-sa 4.0. For media licensing options, please contact [email protected]; Figure 2b. The SINPO-class SSB moved to drydock on imagery from June 10, 2023. Image © 2023 Planet Labs, PBC cc-by-nc-sa 4.0. For media licensing options, please contact [email protected].

The SINPO-class SSB was last observed in the drydock in December 2021 after an at-sea launch of a submarine-launched ballistic missile. It was unclear what work was conducted on the submarine at that time—whether routine maintenance or post-launch repairs.