South Korea is marking a historic milestone in the development of its national fighter jet. The Defense Acquisition Program Administration (DAPA) has announced that the first serial production unit of the domestically developed KF-21 Boramae has entered its final assembly stage. Components integrated include the fuselage, wings, engine covers, tail structures, landing gear, flight control systems, engines, and avionics.
DAPA officials highlighted that this phase signifies “the transition from component production to full aircraft-level integration,” noting that the first production aircraft is now largely complete. Ground and flight testing will follow final assembly.
First delivery in 2026
Production, which began in July 2024, has reached this assembly phase in roughly 10 months. The first KF-21 Boramae is scheduled to be delivered to the Republic of Korea Air Force (ROKAF) in the second half of 2026.
Launched in 2015, the KF-21 program aims to develop a next-generation fighter to replace aging F-4E Phantom II and F-5E/F Tiger II aircraft. Over 600 domestic companies have participated in the 10.5-year development process, with a target of 65% local content. Critical technologies such as the AESA radar and mission computer have been developed by South Korean firms.
$1.41 billion initial production contract
On 25 June 2024, Korea Aerospace Industries (KAI) and DAPA signed a $1.41 billion contract for the low-rate production of 20 KF-21 Block I fighter jets. The contract also includes training and logistical support. A second production contract for another 20 units is planned for 2025.
Twin-engine, high maneuverability
The KF-21 Boramae is powered by two General Electric F414-GE-400K turbofan engines, each providing 97.9 kN of afterburner thrust. Classified as a 4.5-generation fighter, it is designed for air superiority and precision strike missions.
Technical specifications:
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Maximum takeoff weight: 25,600 kg
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Maximum speed: Mach 1.81 (approx. 2,220 km/h)
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Ferry range: 2,870 km
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Payload capacity: 7,700 kg
Its airframe design features twin tails similar to the F-22 Raptor and angular air intakes reminiscent of the F-35A. The internal cannon is located above the left air intake.
Targeting 2,000 flight sorties in tests
The KF-21 completed its maiden flight on 19 July 2022. The test program includes six prototypes, with over 1,000 test flights completed by the end of 2024. The goal is to reach 2,000 sorties by 2026. Tests include night operations, air-to-air missile firings, and aerial refueling. Meteor and IRIS-T missiles have been successfully integrated, while work continues on integrating the Taurus KEPD 350 cruise missile.
Indonesia partnership: Political and technical challenges
The KF-X/IF-X project was launched in 2014 as a joint initiative between South Korea and Indonesia, with Indonesia pledging to cover 20% of development costs. However, delays in payments have occurred since 2018. As of 2024, South Korea has agreed to restructure Indonesia’s contribution, and the partnership was officially reaffirmed in February 2025. Nevertheless, uncertainty remains around Indonesia’s planned order of 50 KF-21 units.
In 2025, a security investigation was launched after two Indonesian engineers at a KAI facility attempted to carry USB devices without authorization. DAPA stated that no data leakage was detected.
DAPA: “The program is at a tangible stage”
Jeong Gyu-heon, Director of Space Command at DAPA, stated, “This achievement was made possible through strong coordination among government agencies, industrial partners, and development institutions.” Officials noted that the first production batch is scheduled to be completed by 2028.
