VECTORDEFENCE DRONE
INTELLIGENCE
INDEPENDENT PERSPECTIVE
THE EVOLVING FIELD GUIDE
Editor

Sea surface · Uncrewed surface vessel

Haegeom / Sea Sword family

A South Korean experimental USV family supporting surveillance and subsequent naval development programmes.

Role & capabilities

  • Maritime surveillance
  • Modular mission equipment
Development / trialsDevelopment / trials
Primary domain
Sea surface
System type
Uncrewed surface vessel
Developer / manufacturer
LIG Nex1
Origin / production countries
South Korea
Other names
Sea Sword; 해검
Variants / configurations
Haegeom-II; Haegeom-III; Haegeom-V; M-Hunter — related research branch; 2024 DAPA reconnaissance USV development
Operators / programme customers
South Korean defence development programme; fleet acceptance not established

Evidence & current status

Public programme evidence establishes the stated maturity only; unreported numerical data remain unknown.

Haegeom, translated as Sea Sword, is LIG Nex1's family of uncrewed surface-vessel demonstrators. The company traces the programme to civil-military development work begun in 2015. Its published portfolio separates several configurations: Haegeom-II supports underwater inspection equipment, Haegeom-III adds a different mission fit, and Haegeom-V is intended for deployment from a supporting ship. M-Hunter is a related mine-countermeasure research branch.

A company-issued December 2023 release described a new systems-integration test facility and reported Haegeom-III sea trials in sea state 4. In December 2024 the company separately announced a DAPA development contract for two approximately 12-metre reconnaissance USVs by 2027. That contract is evidence of funded development, not proof that the earlier demonstrators or the future production design have entered service.

The catalogue keeps the numerical trial claim tied to Haegeom-III and the size description tied to the contracted reconnaissance programme. Different mission modules and support arrangements make a single family-wide performance table misleading. Later customer acceptance records and configuration-specific technical sheets are still needed to establish fleet status and comparable endurance, payload and range figures.

Sourced specifications

Figures apply to the named configuration. Maximum values are not guaranteed operating performance.

SpecificationReported valueContext & source
ConfigurationHaegeom experimental USV familyPublished configuration baseline; not independently demonstrated at every loading and sea condition. Source ↗
Hull / propulsionNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
DimensionsContracted reconnaissance development: 12-metre classDescribes the two-vessel development requirement, not all Haegeom demonstrators. Source ↗
Displacement / massNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
PayloadHaegeom-II: remotely operated underwater inspection modulePublished configuration baseline; not independently demonstrated at every loading and sea condition. Source ↗
EnduranceNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
RangeNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
SpeedNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
Sea state / environmentHaegeom-III: sea state 4 trials reportedSpecific demonstrator trial claim; not a rating for every variant. Source ↗
SensorsNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
Communications / controlNot established in the reviewed public sources.Public evidence gap. No estimate or neighbouring variant value has been substituted. Source ↗
Launch / deploymentHaegeom-V: supporting-ship deployment conceptPublished configuration baseline; not independently demonstrated at every loading and sea condition. Source ↗

Documented milestones

  1. Reconnaissance development contract announced

    LIG Nex1 announced a DAPA contract to develop two 12-metre-class USVs by 2027.

    Read the announcement ↗

Publication history

  • — Added in the September 2026 global coverage review, with sources, configuration limits and explicit data gaps.

Suggest a correction to this entry →

Follow the evidence

Source types identify who makes the claim. Programme milestones and supplier statements should be read in context.

  1. LIG Nex1-issued integration facility and Haegeom variant announcement (opens in a new tab)Manufacturer press release
  2. LIG Nex1-issued reconnaissance USV development contract, 19 December 2024 (opens in a new tab)Manufacturer press release
  3. LIG maritime autonomy portfolio (opens in a new tab)Manufacturer

Explore the connections

Manufacturer indexSouth Korea

LIG Nex1

Systems and source material associated with LIG Nex1.

Reviewed 21 Sept 2026Read
Field guideGlobal

Uncrewed surface vessels & naval drones

Understand surface vessels used for naval observation, survey, mine-countermeasure support and other maritime roles, from small craft to larger experimental ships.

Reviewed 20 Sept 2026Read