Commercial satellite imagery from January 18 reveals new insights about the changes taking place at North Korea’s Sohae Satellite Launching Station. Major modifications are moving ahead quickly at the main launch pad, the Vertical Engine Test Stand (VETS) and the former Control Center area. Additionally, new details can be seen on the tunnel connecting the secure complex to a new pier under construction at the nearby coastal village, suggesting that it will be more than simply a shortcut in and out of the complex, but may also be used as an underground storage area for vehicles and heavy equipment. Work also continues to expand the road network between the coastal village down to the sea and to build a probable new jetty, the combination of which may enable sea-based transport of heavy equipment to the Sohae area in the future.
The pace and level of activity around Sohae to improve both the facilities within the secure complex as well as access to and from the coastal areas are all consistent with Kim Jong Un’s directions issued last year to upgrade and expand the site. They also illustrate the high priority being placed on completing this project to prepare for future satellite and missile launches.
At the launch pad, the roof and sides of the framing structure for the mobile transfer structure have been removed, suggesting the height will be raised to accommodate larger launch vehicles.
The transfer structure has been moved away from the final preparation building exposing a rectangular opening to the rail transfer tunnel, where rocket segments arrive by rail and are raised up onto the platform. The opening measures 18 meters in length. An antenna tower, which probably provides data linking to the launch vehicle telemetry system during the first 10-20 seconds of a launch, is also visible.
A new launch stand ring, likely meant to accommodate the blast from wider and more powerful launch vehicles, is sitting in front of the tower, waiting to be installed.
Additional gantry tower sections have arrived on the pad. These will be used to increase the height of the launch gantry to accommodate larger rockets.
Finally, construction appears suspended on the two new buildings just west of the launch pad; their purpose is yet unclear.
Figure 1. Materials loaded on the launch pad for multiple modifications.
Engine Test Stands
At the VETS, what appear to be piles of dirt have been placed on the east side of the apron alongside the rail-mounted mobile shelter. The dirt seems to be intended for use in the ongoing road construction efforts across from the Horizontal Rocket Motor Test Stand. That road segment, previously thought to be a turn-around for vehicles moving engines to the test stand, is being extended approximately 150 meters northward. A steep pitch down the mountain begins at its terminus, begging the purpose of this extension.
Figure 2. Dirt piles on the VETS, probably for road work.
Former Control Center Area
The new building where the former launch control building once stood will be approximately 120 meters in length and 60 meters in width. The north and west sides of the building are being configured with numerous smaller, office-sized rooms; the western part of the building is designed as a larger, central open-bay room.
Figure 3. Building construction continues at the former Control Center location. Spring crops visible along main roadway.
Construction on the new tunnel, which will connect the secure complex to the village of Changya-dong to the east and a coastal road that extends down the length of the Sohae peninsula, is continuing at a rapid pace. At both ends of the tunnel, arched, reinforced concrete headworks are in place, each measuring 15 meters in width. At the southeast entrance, the reinforced concrete roof extends at least for 50 meters already but is not yet complete. Concrete is probably necessary due to the local geography and the depth of the bedrock. Most of the spoil removed so far appears to be earth as opposed to rock fragments.
A second, much smaller tunnel entrance is now visible below the grade of the larger tunnel, suggesting that there will be a multi-level tunnel system inside the mountain. This, and the unusually large width of the concrete entranceways, suggest that the tunnel will serve as more than a vehicle passageway but may accommodate multiple functions, such as for mobile missile storage or an underground operations center.
Figure 4. Concrete reinforcement of tunnel entrances and roof and evidence of an additional, smaller entrance.
East Coast Roadway and Jetty Pier
Amid efforts to build a new road network along the eastern coastline, it appears a second roadway is being constructed from Changya-dong to a small village at the southeast point of the Sohae peninsula. The new road is wider and will have fewer curves and less of a grade for vehicles to negotiate.
At the southeast village, work has been underway to add what will likely be a jetty pier, which extends directly south into the sea. Jetties are often used to protect a coastline, but they can also be used to extend out to deeper waters so that ships can berth at them. Most of the coast in this area is shallow and affected by the daily tides. The location of this jetty will reach out beyond the shallows, suggesting it may be suitable to receive heavy equipment in the future, providing an alternative transport option to rail.
Figure 5. Work continues on new jetty into the sea.
The other facilities within the Sohae complex have seen little change in the past two months. That said, despite the construction activity and the passage of vehicles through the surrounding fields, the spring crops are evident in the fields along the main road of the complex, from the main gate to the launch pad area (see Figure 3).