North Korea’s recent launch of the Kwangmyongsong-4 satellite has also raised concerns about its continuing development of the Bukkeukseong-1 (Polaris-1, KN-11) submarine-launched ballistic missile (SLBM) and the GORAE-class experimental ballistic missile submarine. Recent commercial satellite imagery of the Sinpo South Shipyard indicates that North Korea is continuing to actively pursue development of both programs. Specifically:
- Unidentified work on the GORAE-class submarine during the past two months appears to have been completed. A heavy crane, engaged in that activity, has been moved to the pop-up test stand for work on the support tower.
- Construction and refurbishment continues at halls that will be capable of building submarines larger than the GORAE-class when completed.
- The removable tower—moved to the test stand to support a rocket engine, missile or launch tube and then removed—has remained in place for the past two months, allowing the North to more quickly conduct a pop-up test.
Despite legitimate concerns about North Korea’s development of a SLBM and a ballistic missile submarine having a significant effect upon regional security, these developments represent an emerging rather than a current threat. Deployment of such operational systems will be an expensive, time-consuming endeavor for North Korea and there is no guarantee of success. Regardless, these programs require continual monitoring to ensure appropriate responses are in place if or when they reach fruition.
Work on GORAE-Class Submarine Completed
Recent commercial satellite imagery indicates that unspecified work on the GORAE-class experimental ballistic missile submarine over the past two months may be complete. The submarine is present within the secure boat basin at the Sinpo South Shipyard in the January 27 and February 16 imagery along with the submersible test stand barge and a support vessel. The netting draped over the decks of the submarine, first seen in early January, remains in place, concealing any work. The heavy crane, however, also seen throughout January, is no longer present and appears to have moved to the test stand in the February 16 image. Also visible in the latest imagery is what appears to be a large shipping container or tank adjacent to the submarine and a small number of people moving about on the dock. The container or tank (approximately 10 meters long by 2.5 meters in diameter) is larger than the missile-shipping container spotted last May that measured 9.5 meters long by 1.5 meters in diameter. The purpose of this container or tank is unclear.
Figure 1. The secure boat basin at the Sinpo South Shipyard on January 27, 2016.
Figure 2. The secure boat basin at the Sinpo South Shipyard on February 16, 2016.
The submersible test stand barge remains in the same location as it did in January and retains the netting draped over it, partially concealing details of any activity. No personnel are seen working near the barge.
A small support vessel not present in the December imagery is now visible in the January and February imagery and is docked at a location at the north end of the secure boat basin. It is believed that this vessel is used to tow the submersible test stand barge and support the submarine during ejection tests.
Refurbishment of Submarine Construction Facilities
Construction and refurbishment activity at the submarine construction hall, 400 meters to the south of the boat basin, continues at a slow pace. Only minor activity is observed on the launching ramp—most likely due to winter weather. When work on the construction halls, fabrication buildings and machine shops is completed, these facilities will be able to build new submarines much larger than the GORAE-class.
Figure 3. Main Construction Hall and ramp on January 27, 2016.
Figure 4. Main Construction Hall and ramp on February 16, 2016.
Ability to Conduct Pop-Up Tests More Quickly
Imagery indicates that the removable tower used to support a rocket engine, missile or launch tube at the test stand 1,100 meters to the southwest of the secure boat basin has remained in place for several months. Leaving the tower in place—somewhat counter to previous practice when it was erected just before a test and then removed afterwards—allows the North Koreans to more quickly conduct a “pop-up” or ejection test with little advance warning. In the February 16 image, the pad has been cleared of snow. The heavy crane, previously located at the submarine, is present and appears to be working on the test stand’s support tower. The purpose of this activity remains unclear however.
Figure 5. Test Stand at the Sinpo South Shipyard on January 27, 2016.
Figure 6. Test Stand at the Sinpo South Shipyard on February 16, 2016.
 North Korea conducted an “ejection” test of the Bukkeukseong-1 (Polaris-1, KN-11) submarine-launched ballistic missile (SLBM) on December 21, 2015, that appears to have failed. Gorae is Korean for whale. This boat was previously identified as the SINPO-class experimental ballistic missile submarine (SSBA).
 Joseph S. Bermudez Jr., “North Korea’s Ballistic Missile Submarine Program: Full Steam Ahead,” 38 North, January 5, 2016, https://www.38north.org/2016/01/sinpo010516/.
 Due to the recent snow fall, the look angle of the satellite and the reflection of the sunlight many details are not clearly visible in the February 16 image.
 Bermudez Jr., Joseph S. “Underwater Test-fire of Korean-style Powerful Strategic Submarine Ballistic Missile,” 38 North, May 13, 2015, https://www.38north.org/2015/05/jbermudez051315/.