South Korea Moves to Integrate Locally Developed Long-Range Air-to-Air Missile on KF-21 Fighter Jet.

Korea Aerospace Industries and Hyundai Rotem agreed to jointly develop and integrate a South Korean long-range air-to-air missile for the KF-21 Boramae, expanding the fighter’s future domestic weapons package. The move could reduce Seoul’s reliance on foreign missile suppliers while giving prospective KF-21 customers access to a more autonomous aircraft and weapons combination.

The agreement, signed on August 12, 2026, at KAI headquarters in Sacheon, covers airborne weapon development, systems integration and export packages combining Korean combat aircraft with locally produced armament. Hyundai Rotem is already involved in propulsion work for the missile, including a ducted ramjet concept designed to sustain energy later in flight, while KAI will support integration with the KF-21’s AESA radar, mission computer and stores management architecture. South Korea’s long-range air-to-air missile program is scheduled to run from 2026 to 2033 under the Agency for Defense Development, with an estimated budget of 753.5 billion won, as Seoul prepares the KF-21 for broader domestic service and potential export campaigns.

Related News: South Korea's first serial KF-21 Boramae fighter jet completes maiden flight 22 days after rollout

The KF-21 Boramae is expected to integrate a South Korean-developed long-range air-to-air missile under a national program led by the Agency for Defense Development. (Picture source: KAI)

The agreement comes as South Korea enters the development phase of its national long-range guided air-to-air missile program. The Defense Acquisition Program Administration approved the development plan in September 2025, assigning the Agency for Defense Development responsibility for a program scheduled to run from 2026 to 2033 with an estimated budget of 753.5 billion won. The objective is to equip the KF-21 with a domestic weapon while creating the conditions for joint exports of the aircraft and missile. This approach reduces exposure to foreign weapon release approvals and integration restrictions, an issue that carries greater weight as Seoul seeks to expand its presence in the international combat aircraft market.

According to information released by Hyundai Rotem following the signing, the company is already involved in prototype work on a ducted ramjet propulsion system intended for the future missile. This architecture uses atmospheric air in the combustion process rather than carrying the full oxidizer supply onboard. Compared with a conventional solid rocket motor, it can maintain thrust over a larger portion of the flight profile and preserve more energy during the later stages of an interception. The technical challenge lies partly in managing airflow and combustion across a wide range of altitudes and speeds, an area in which Hyundai Rotem is also developing expertise linked to ramjet and hypersonic propulsion systems.

Integration with the KF-21 will depend as much on sensors and mission systems as on missile propulsion. The fighter is equipped with an active electronically scanned array radar developed in South Korea as part of the KF-21 program. DAPA has stated that testing has covered air-to-air detection and tracking functions as well as synthetic aperture radar imaging, with 50 flights planned to assess around 62 parameters. These functions form an essential part of the detection and targeting chain required for beyond-visual-range engagements and the employment of long-range weapons.

The domestic missile will enter an aircraft ecosystem already prepared for modern BVR armament. KF-21 prototypes have conducted weapon separation trials, while the program has used the MBDA Meteor as an operational reference. KAI therefore already has experience integrating an advanced air-to-air missile into the fighter’s stores management and mission systems architecture. A South Korean missile will nevertheless require its own certification process, including aerodynamic validation, software interfaces, weapon employment logic and interaction with the radar and mission computer. Cooperation with Hyundai Rotem therefore concerns not only physical carriage but also integration across the broader combat system.

Operationally, a nationally controlled long-range missile would give the Republic of Korea Air Force greater flexibility in defining the KF-21’s engagement envelope. A ramjet-type propulsion system is relevant in this context because it can retain more energy during the terminal phase, when a target attempts to defeat the intercept through hard turns, altitude changes or acceleration. Combined with an AESA radar and networked targeting data, such a weapon could allow KF-21 formations to engage fighters or support aircraft before entering shorter-range threat envelopes. Actual detection and launch distances will, however, depend on target radar cross-section, altitude, engagement geometry, the electronic warfare environment and missile seeker performance.

This capability would enter a South Korean fleet that already combines the F-35A and F-15K, two platforms oriented respectively toward low-observable penetration and heavier long-range missions. The KF-21 adds additional force capacity, a nationally controlled architecture that can be upgraded over time, and more room to integrate Korean weapons without relying systematically on an external supplier. DAPA is also pursuing an upgrade of the F-15K with new mission equipment, radar and electronic warfare systems, indicating that Seoul is not replacing one capability with another but building a more complementary combat aviation structure.

The same logic applies to exports. Several countries have already shown interest in the KF-21. Indonesia remains associated with the program and discussions have addressed the acquisition of production aircraft, while the United Arab Emirates, the Philippines and Malaysia are among the countries frequently cited as potential customers. Poland and Saudi Arabia have also examined the platform through senior-level visits and industrial discussions. For Seoul, eventually offering the KF-21 together with a domestic long-range air-to-air missile would reduce a customer’s dependence on multiple foreign supply chains and turn the aircraft into a more complete combat package. It would also place South Korea in a stronger position in a market where buyers increasingly negotiate performance, industrial participation, operational autonomy and integration freedom at the same time.

Written By Erwan Halna du Fretay - Defense Analyst, Army Recognition Group
Erwan Halna du Fretay holds a Master’s degree in International Relations and has experience studying conflicts and global arms transfers. His research interests lie in Security and strategic studies, particularly the dynamics of the defense industry, the evolution of military technologies, and the strategic transformation of armed forces.