South Korea's military admits its system for fusing spy satellite imagery falls short

South Korea's top military officer has acknowledged that the system meant to merge imagery from the country's new reconnaissance satellites with other surveillance data is not performing as required. The admission came on 26 October at the National Assembly defence committee's annual audit of the defence ministry and the Joint Chiefs of Staff (JCS), where a lawmaker accused the military of putting satellites into orbit while neglecting the ground system needed to use them.

Kim Sung-hoe, a Democratic Party lawmaker, said development of the military's multi-source intelligence fusion system had been slipping since 2022, while the complete version is not planned until 2033. He said the military was spending trillions of won to launch satellites but that the ground segment could not properly take in and combine what they collected, and he asked what would become of the satellites already in orbit by the time the full system arrived.

According to Kim, an evaluation of the basic version found that it slowed down as the number of incoming images grew and became unstable when several users logged in at once. He told the hearing that an analyst wanting the 18th of 20 images had to wait for the first 17 to download. He also noted that the satellites have a design life of about five years, so the current fleet could reach the end of its service before the finished fusion system is fielded.

The JCS chairman told the committee that he accepted that parts of the system's performance were inadequate and that some technical elements were lacking. He also warned that putting the programme through another audit could make the military more reluctant to take on demanding projects. A JCS official answering questions agreed that the basic version was much slower than the analysts' own tools and confirmed that analysts preferred their own systems. Defence Minister Kang Shin-chul said he would look into the matter.

Kim formally asked the committee to vote to request an audit by the Board of Audit and Inspection covering both the fusion system and the wider plans for intelligence, surveillance and reconnaissance (ISR), including the satellites. He argued that once wartime operational control passes to Seoul, a Korean-led combined defence will depend on linking many ISR assets to support commanders' decisions, not just on the quality of individual satellites. Kuki News noted that his claims about deliberate delay and wasted money still need further verification.

Five satellites, one bottleneck

The satellites at issue belong to the 425 Project, which planned five large military reconnaissance satellites: one electro-optical and infrared satellite and four synthetic aperture radar satellites. The first was launched on a SpaceX Falcon 9 from Vandenberg Space Force Base in California in December 2023, and the fifth was due to enter service in June 2026. With all five in orbit, the military expected to image key North Korean sites such as missile bases roughly every two hours, Asia Business Daily reported in April.

The same report described an earlier version of the bottleneck. Ground tests before launch had covered only about ten images at a time, but once the satellites began sending more than 100 images totalling hundreds of gigabits, the ground station could not pass them to the multi-source fusion system. The arms procurement agency had to build dedicated servers and new interface equipment, a job LIG Nex1 finished in December 2025. The report also said the military had only about 210 ISR imagery specialists, with plans to reach about 280.

Seoul is already planning more. A follow-on Reconnaissance Satellite II programme worth about 1.3 trillion won is meant to replace the current five from 2031, and around 40 small and micro reconnaissance satellites are planned to enter service in the late 2020s, cutting revisit times over the peninsula to about 30 minutes. Kim's complaint was that the 2033 timeline for the complete fusion system would come after those additional constellations begin launching.