South Korea has reached a tentative agreement to transfer a KF-21 Boramae fighter jet prototype to Indonesia following financial challenges in their joint development program. The deal, valued at approximately 600 billion won ($406 million), includes a single-seat prototype along with associated development costs.
The aircraft is one of six prototypes developed by South Korea for testing purposes, including aerial refueling trials. The final delivery timeline will be confirmed once Indonesia clears its remaining financial commitments, expected by June.
The KF-21 program, South Korea’s first indigenous supersonic fighter initiative, began in 2015 in partnership with Indonesia and is scheduled for completion by June 2026. Under the original agreement, Indonesia committed to funding about 1.6 trillion won (around 20 percent) of the total 8.1 trillion won program cost in exchange for a prototype aircraft and technology transfers.
However, financial difficulties arose after Indonesia paused payments following an initial contribution of 227 billion won, leading to the withdrawal of its engineers from the project. Jakarta later proposed reducing its contribution to roughly 600 billion won in exchange for scaled-back technology transfer, aligning with the revised arrangement to receive one prototype aircraft.
The updated cost-sharing agreement was formalized in June 2025, with Indonesia having paid around 500 billion won so far. The KF-21 is intended to replace South Korea’s aging F-4 and F-5 fleets by 2030. The first prototype was unveiled in 2021 and flew in 2022, with mass production beginning in 2024 and the first production model revealed in March 2026. Deployment is planned for September.
Despite earlier setbacks, South Korean President Lee Jae Myung and Indonesian President Prabowo Subianto recently reaffirmed their commitment to joint defense cooperation during a summit in Seoul, including collaboration on trainer aircraft and anti-tank missile systems. Indonesia is also reportedly considering the purchase of 16 KF-21 jets, which would make it the first export customer if finalized.
