South Korea has tentatively agreed to transfer one KF-21 Boramae fighter jet prototype to Indonesia, following financial disputes in their joint development partnership.
The deal, valued at roughly 600 billion won ($406 million), covers a single-seat KF-21 prototype and other development costs, Korea Times reported, citing South Korean lawmaker Kang Dae-sik.
The aircraft is one of six prototypes Seoul has built and used for testing, including aerial refueling.
The delivery date will be finalized once Indonesia settles its remaining project balance, expected by June.
Financial Issues
The KF-21 is South Korea’s first homegrown supersonic fighter jet, created in cooperation with Indonesia.
Joint development began in 2015 and is on track to conclude in June 2026.
Jakarta initially agreed to cover approximately 1.6 trillion won ($1.08 billion) — around 20 percent — of the program’s total cost of 8.1 trillion won ($5.48 billion), in exchange for one prototype jet and technology transfers.
Funding issues emerged after Indonesia halted payments following a 227 billion won ($195 million) investment, leading to Indonesian engineers leaving the program.
The Southeast Asian country later proposed cutting its contribution to around 600 billion won in exchange for reducing the level of technology transfers, matching the latest deal of handing over one test aircraft.
The two countries formalized the updated cost-sharing arrangement in June 2025, with around 500 billion won ($338 million) paid by Indonesia to date.
KF-21 Program
The KF-21 is designed to replace South Korea’s US-developed F-4 and F-5 fleets by 2030.
The first prototype was rolled out in 2021 and conducted its maiden flight a year later.
Mass production began in 2024, with the first model unveiled in March 2026. Deployment is planned for September.
Despite program setbacks, South Korean President Lee Jae Myung and Indonesian President Prabowo Subianto reaffirmed cooperation on joint defense projects, including trainer aircraft and anti-tank missile systems, during a recent Seoul summit.
Jakarta is also reportedly in talks to buy 16 KF-21s. If finalized, Indonesia would become the first export customer and mark Seoul’s first overseas sale of the fighter.
