A North Korean naval corvette on the east coast sailed to a repair yard this week, a possible sign of efforts to finally officially deploy the ship after a troubled development spanning 14 years.

According to NK Pro analysis of Planet Labs satellite imagery, the 77-meter vessel unofficially dubbed a Tuman-class corvette disappeared between Sept. 23 and 25 from the October 3 Factory under KPA Navy Unit 597 in Munchon, north of Wonsan.

It appeared to arrive at the Mayang Island naval base up the coast between Sept. 25 and 27, before moving into a dry dock at the base by Sept. 29 and remaining there as of the latest imagery taken on Oct. 2. The base is located off the shore of Sinpho, home to the country’s ballistic missile and nuclear submarine projects.

North Korea has still not officially launched the ship or announced its name or designation, while satellite imagery suggests it has not been operationally deployed despite a short stint at the KPA Navy Unit 155 base in March 2024. 

It has otherwise been docked consistently at the October 3 Factory since Dec. 2023, where it may have undergone occasional maintenance or equipment installations. It was previously docked at the Rajin Shipyard in Rason.

North Korean state media has only suggested that one of four similar corvettes has been operationally deployed, when it reported in Aug. 2023 that leader Kim Jong Un oversaw a test launch from what it called the “Patrol Ship No. 661” of a nuclear-capable cruise missile.

The No. 661 ship, unofficially dubbed an Amnok-class corvette, is also based on the east coast, mostly appearing to sail around the Kumgang and Kosong coast near the inter-Korean border since March 2024. It remained at a former tourist pier at Kosong as of the latest imagery on Oct. 2.

This ship also appeared inside the Mayang Island dry dock from Sept. to Oct. 2023, after Kim’s missile test inspection but before moving to Kosong — suggesting the Tuman-class ship’s current trip to Mayang may be related to its long-awaited deployment.

There are also two similar corvettes on the west coast, one called an Amnok-class and one a Tuman-class. The Tuman-class ship appears with a grey deck in satellite imagery and has been stationed at the Pipha naval base west of Nampho for long periods, suggesting it may be operationally deployed despite never being featured in an official launch ceremony.

It was also at the Nampho Shipyard between April and September this year, before returning to Pipha where it appeared in latest imagery on Oct. 1.

The Amnok-class corvette appears with a more reddish deck in satellite imagery and has been mostly stationed at the Nampho Shipyard in recent years, including as of Sept. 29. Kim Jong Un inspected the unfinished vessel there during a visit in early 2024.

Analysts have said that while the corvettes could serve as yet another mobile launch platform for North Korea’s nuclear weapons, the ships are no match for the U.S. and ROK navies and would quickly be targeted in a conflict.

Kim Jong Un has largely shifted the navy’s focus from the troubled corvette development to rapidly building two much larger destroyers since early 2024. He has declared his intention to build two more by the end of 2025, as well as even larger cruisers in the future, as part of plans to eventually operate a blue-water navy and send ships to loiter outside U.S. naval bases. 

The first Choe Hyon-class destroyer, called the No. 51 Choe Hyon, was built at the west coast Nampho Shipyard in April 2025. It appeared inside a floating dry dock at the shipyard between Sept. 9 and 25 as it continues to undergo significant work ahead of its planned deployment to the east coast “early” next year.

The second Choe Hyon-class destroyer, called the No. 52 Kang Gon, was built at the east coast Chongjin Shipyard and launched at the Rajin Shipyard in June 2025. It returned to the Chongjin Shipyard in August, where Planet Labs imagery shows it still undergoing work on Oct. 2 before it is deployed “in the middle of next year.”

Work officially started on the third destroyer at Nampho Shipyard in July, while imagery suggests construction scheduled for the fourth ship at Chongjin has not yet begun, though preparations are underway.

Edited by Bryan Betts