South Korea's homegrown loitering munition crashes twice in maritime trials

A high-end loitering munition developed by the Agency for Defense Development crashed twice in succession during maritime combat trials, dealing a setback to one of South Korea's most ambitious drone programs.

On Tuesday afternoon in the waters off the southern coast, the Navy's amphibious assault ship Marado — a 14,000-ton landing platform helicopter — formed up one nautical mile behind the landing ship Jeonbuk, which led the formation. About one mile off the starboard side, a high-speed unmanned target vessel sat waiting.

The planned scenario called for a loitering munition to launch from Marado's flight deck, fly a 10-mile round trip and strike and sink the moving maritime target.

The drone used in the test had a wingspan of roughly 3 meters and an endurance of more than 10 hours, and was designed to conduct reconnaissance, search and strike missions simultaneously. It features anti-jamming technology and enhanced communications security, along with electro-optical and infrared cameras and an automatic target recognition system that allows it to identify and engage targets day or night and in adverse weather.

At a pre-test briefing, an ADD official said the drone represented "a high-end asset packed with advanced technology — a different class entirely from the low-cost loitering munitions like the Shahed and Lancet that gained prominence in the Russia-Ukraine war," adding that its performance was "superior to, or at least on par with, Israel Aerospace Industries' Harop," a comparable system.

But when the moment came, the drone fell limply into the sea almost immediately after liftoff.

The failure of a key defense technology project so close to completion has raised concerns that the setback could slow the development of South Korea's manned-unmanned teaming combat systems.

ADD said, however, that the crashes do not amount to a wholesale failure of the underlying technology. Key sequences in the launch system — including rocket booster separation and engine engagement — functioned normally, and officials said there were meaningful technical achievements confirmed during the tests.

The drone is an asset ADD has been developing since April 2024 under a core technology research and development project, with the program set to conclude in September.

Speaking with reporters immediately after the test, an ADD official said the cause remained "unknown at this point" and could not specify what led to the crashes. If the investigation drags on, it could affect both the September project completion deadline and the subsequent operational readiness program schedule, observers noted.

ADD said it does not believe the crashes point to a defect in the drone's core airframe technology. Before Tuesday's incidents, the drone had completed more than 30 sorties since its maiden flight in December last year, achieving a 100 percent hit rate against both fixed and moving targets across a range of environments.

"There was not a single similar crash incident during ground-based tests," an ADD official said.

The launch sequence itself — including rocket-assisted ejection separation and normal engine RPM — was confirmed to have operated correctly in both attempts. ADD therefore suspects the cause may not lie in the drone's core flight or strike technology but rather in a minor misalignment that could have occurred during disassembly and reassembly aboard the ship.

When asked by reporters whether the assembly and reassembly process itself was at fault, the official said, "We don't believe there was a methodological problem." The official added that before the first launch, part of the final inspection could not be visually confirmed, which raised suspicion — but that a similar symptom recurred during the second attempt even after a direct hands-on inspection.

On the possibility that the maritime environment contributed to the crashes, the official said, "There were no issues in the real-time data, and we will conduct a comprehensive review during maintenance checks after returning to base."

ADD plans to conduct a precise analysis of ground control system data collected during the tests to determine the cause, and will carry out further trials to verify the drone's operational viability at sea.