Korea's KF-21 fighter jet receives combat suitability approval, paving way for deployment this year

Korea’s homegrown KF-21 fighter jet has cleared its final development hurdle by winning combat suitability approval 11 years after the program began, paving the way for front line deployment later this year.

The KF-21 fighter jet at its launch ceremony on March 25 at the Korea Aerospace Industries headquarters in Sacheon, South Gyeongsang. [JOINT PRESS CORPS]

Korea’s homegrown KF-21 fighter jet has cleared its final development hurdle by winning combat suitability approval 11 years after the program began, paving the way for front-line deployment later this year, the Defense Acquisition Program Administration (DAPA) said Wednesday.

The decision marks a major step for Korea’s defense industry, with officials saying it opens a new era in which Korea can now defend its airspace with a fighter developed with indigenous technology.

The KF-21 is a 4.5-generation supersonic fighter developed by Korea Aerospace Industries (KAI), in collaboration with the Air Force and the Agency for Defense Development.

The project is meant to replace the Air Force’s aging F-4 and F-5 fighters and strengthen readiness for future air combat. DAPA signed the main system development contract with KAI in December 2015 and launched the project the following month.

The KF-21 underwent about five years of ground testing from May 2021 through February this year to verify durability and structural soundness, according to DAPA.

During this period, the KF-21 reportedly completed more than 1,600 test flights without a single accident and passed roughly 13,000 test conditions, including aerial refueling and weapons launch tests.

Officials said the aircraft meets the Air Force’s required operational capabilities and has secured the technical level needed to carry out actual combat missions.

The KF-21 Boramae fighter jet flies across the sky near Seoul Air Base in Seongnam, Gyeonggi, on Oct. 17, 2025. [YONHAP]

The KF-21 prototype made its first successful test flight with the Air Force’s 3rd Flying Training Wing in July 2022. It later passed tests for supersonic flight, night flight, active electronically scanned array (AESA) radar integration and air-to-air missile launches. A provisional combat suitability ruling in May 2023 allowed the program to move into mass production.

The Korean fighter jet is fitted with a Hanwha Systems-developed AESA radar, a technology Washington previously denied transferring to Seoul. The AESA radar allows the aircraft to detect and track multiple targets simultaneously.

DAPA plans to formally wrap up system development in June and begin delivering production aircraft to the Air Force in the second half of the year. The goal is to place the first aircraft into service in September. Korea plans to produce 40 Block-I fighters first — 20 by 2027 and another 20 by 2028 — with a focus mainly on air-to-air missions.

"Additional weapons tests will also be conducted to secure air-to-ground strike capability for the KF-21," a DAPA official said.

Indonesia, the program’s partner country, is considering purchasing 16 Block-II jets, which would add air-to-ground and air-to-ship capabilities.

President Lee Jae Myung delivers remarks at a ceremony marking the rollout of the first mass-produced KF-21 fighter jet at Korea Aerospace Industries in Sacheon, South Gyeongsang, on March 25. [JOINT PRESS CORPS]

“This combat suitability decision is a symbolic achievement showing that Korea has fully secured independent fighter development capability,” Noh Ji-man, head of DAPA’s Korean Fighter Program Division, said. “We will push ahead smoothly with mass production and deployment to further strengthen the Air Force’s operational capabilities.”

This article was originally written in Korean and translated by a bilingual reporter with the help of generative AI tools. It was then edited by a native English-speaking editor. All AI-assisted translations are reviewed and refined by our newsroom. BY SHIM SEOK-YONG [cho.yongjun1@joongang.co.kr]