Gorae-class ballistic missile submarine

History

The Gorae class, also known as the Sinpo class, is a North Korean diesel-electric ballistic missile submarine developed as a platform for submarine-launched ballistic missile testing. North Korea possesses a single known vessel of the class, named 8.24 Yongung, or August 24th Hero.

The submarine represents an early stage in North Korea's effort to establish a sea-based ballistic missile capability. Its limited size, single missile tube, conventional propulsion and restricted endurance distinguish it from larger strategic ballistic missile submarines.

The vessel has primarily been associated with development and testing of North Korean submarine-launched ballistic missiles. Its precise operational role remains uncertain, and several independent analyses have described it principally as an experimental or limited-capability platform.

Development and launch

According to the Nuclear Threat Initiative, the single Gorae-class submarine was launched in March 2014. The submarine was subsequently observed at the Sinpo South Naval Shipyard in satellite imagery from July 2014. Specialist analysis published by Covert Shores noted that the previously undeclared submarine appeared outside the shipyard between late April and July 2014.

The emergence of the submarine coincided with construction and activity associated with submerged missile testing at Sinpo. A submersible test barge was used for early ejection and launch work so that missile development could proceed without risking the submarine itself.

Missile testing

Open-source accounts differ over whether the Gorae participated directly in missile launches during late 2015. Reports attribute several tests during that period to either the submarine or a submerged test platform. By 2016, however, the Gorae had become closely associated with testing of the Pukguksong-1, also known as KN-11.

On 24 August 2016, North Korea conducted a successful Pukguksong-1 submarine-launched ballistic missile test. Covert Shores reported that the missile travelled about 500 km on a lofted trajectory and assessed the event as a major demonstration of the developing system.

On 20 October 2021, North Korea announced another submarine-launched ballistic missile test from a Gorae-class submarine off Sinpo. NTI reports that the missile travelled about 600 km and reached an altitude of approximately 60 km. The launch reportedly caused damage to the submarine, which was subsequently towed back to the pier, although later assessments indicated that it returned to normal activity.

Later activity

By 2025, satellite imagery continued to show 8.24 Yongung at the Sinpo South Shipyard. A July 2025 analysis by Beyond Parallel identified the submarine alongside the secure boat basin and noted objects on the deck aft of the conning tower associated with ongoing work of uncertain purpose.

In 2026, commercial satellite imagery showed the Gorae-class submarine inside a drydock at Sinpo South Shipyard. Military Watch Magazine reported that the vessel had spent at least some time in the drydock before returning to the secure boat basin. The nature and extent of the work were not confirmed, although refurbishment or upgrades were considered possible.

Design

The Gorae class is a conventionally powered ballistic missile submarine with diesel-electric propulsion. It does not have a confirmed air-independent propulsion system. This requires the submarine to surface or snorkel periodically to recharge its batteries and limits the duration of submerged operations compared with submarines equipped with air-independent or nuclear propulsion.

The submarine carries a single vertical ballistic missile launch tube integrated into the sail. This arrangement allowed North Korea to field a relatively compact test submarine while accommodating a submarine-launched ballistic missile and its associated launch equipment.

Specialist analysis describes the submarine as a single-hull design. The forward section is assessed to contain sonar, ballast and control spaces, while machinery and propulsion equipment occupy much of the after section. Possible torpedo tubes have been discussed in open-source analysis, but their number and configuration have not been conclusively established.

Available estimates of crew size differ substantially. NTI lists a crew of 35, while Covert Shores has estimated approximately 70 to 80 personnel from imagery. Because of this disagreement, the exact complement is uncertain.

Propulsion and endurance

NTI describes the submarine as diesel-electric and states that it lacks air-independent propulsion. Its submerged endurance is therefore limited to a few days before battery charging is required. NTI estimates an effective range of approximately 1,500 nautical miles. Covert Shores has separately estimated total endurance at about one month or less.

Missile armament

The Gorae class has one confirmed ballistic missile tube and has served as a test platform for submarine-launched ballistic missiles. It is particularly associated with the Pukguksong-1, or KN-11, solid-fuel missile. The submarine's single-tube arrangement and limited endurance have led analysts to characterize it as primarily an experimental platform rather than a mature strategic patrol submarine.

Program status

Only one Gorae-class submarine is known. The vessel remains associated with the Korean People's Navy and the Sinpo South Shipyard, but its current operational status is uncertain. Evidence of continued maintenance and drydock work indicates that the submarine has not simply been abandoned despite the emergence of newer North Korean ballistic missile submarine designs.

The Gorae provided an important development platform for submarine-launched ballistic missile testing and preceded larger North Korean submarine projects. The degree to which it can perform an operational deterrent mission, rather than testing and training, has not been publicly established.

Operators

• North Korea: The Korean People's Navy possesses one known Gorae-class submarine, 8.24 Yongung. It has been used for submarine-launched ballistic missile development and testing, while its broader operational status remains uncertain.

Specifications (Gorae-class 8.24 Yongung)

General characteristics

• Type: Diesel-electric ballistic missile submarine
• Length: 66.75 m according to NTI; Covert Shores gives a provisional estimate of about 68 m
• Beam: 6.7 m according to NTI; Covert Shores estimates about 6.5 m
• Propulsion: Diesel-electric
• Air-independent propulsion: Not fitted according to available assessments
• Known vessels: One

Performance

• Maximum speed: About 10 knots according to NTI
• Estimated effective range: Approximately 1,500 nautical miles according to NTI
• Estimated endurance: Approximately one month or less according to Covert Shores, with submerged endurance limited by the need to recharge batteries

Armament

• Ballistic missile capacity: One submarine-launched ballistic missile
• Associated missile: Pukguksong-1, also known as KN-11

Related equipment

The Gorae program preceded later North Korean ballistic missile submarine developments. These include the larger Sinpo-C or modified Romeo-class design and the No. 841 Hero Kim Kun Ok submarine launched in September 2023. The newer submarines are separate designs and should not be treated as Gorae-class variants.