South Korea Delivers First Production KF-21 Boramae to ROKAF

South Korea’s indigenous fighter program transitioned from development to operational service on September 22, 2026, with the delivery of the first mass-produced KF-21 Boramae Block I to the Republic of Korea Air Forces (ROKAF).

The milestone, announced in a joint press release by ROKAF and the Defense Acquisition Program Administration (DAPA), culminates a 25-year effort to field a domestically developed advanced fighter. Aircraft No. 001 was flown from the Korea Aerospace Industries (KAI) manufacturing plant in Sacheon to Yecheon Air Base in North Gyeongsang Province.

Delivery and escort flight

The inaugural operational sortie was piloted by Maj. Han Jae-seok of the 156th Fighter Squadron. During the transit flight, the KF-21 was escorted by an FA-50 light attack aircraft, a TA-50 fighter trainer, and a T-50 Golden Eagle jet trainer. According to Yonhap News Agency, this formation was designed to symbolize the generational progression of South Korea’s indigenous military-aircraft aviation industry.

ROKAF Chief of Staff Gen. Son Sug-rag emphasized the significance of the handover, describing the delivery as a historic milestone in achieving self-reliant national defense.

Overcoming numerous trials and hardships, the KF-21 was handed over to the Air Force today and commenced flight operations. Up until yesterday was the time for the Boramae project’s policymakers and developers. From today onward, it is the Air Force’s time.

Fleet integration and production timeline

The aircraft will be operated by the 156th Fighter Squadron, which ROKAF reactivated on June 1, 2026. The squadron previously operated F-4E Phantom II fighters before being disbanded in 2012, according to reporting by Janes.

DAPA awarded KAI a $1.4 billion contract in June 2024 to begin production of the first 20 Block I jets. Breaking Defense reports that ROKAF expects delivery of 40 Block I aircraft by 2028, followed by 80 Block II aircraft by 2032, bringing the total planned KF-21 fleet to 120 airframes. The platform is expected to be declared fully combat operational in the second half of 2027.

Development and testing milestones

South Korea first announced plans to develop an indigenous advanced fighter in March 2001. Full-scale system development formally began in December 2015, and KAI rolled out the first prototype in April 2021.

Before achieving combat suitability certification on May 7, 2026, the KF-21 program completed 1,600 flight tests covering 13,000 test conditions, according to AeroMorning. The transition to mass production was authorized in June 2024 following the successful completion of these initial testing phases.

AirPro News analysis

We view the delivery of the first production KF-21 as a critical step in South Korea’s broader strategy to reduce reliance on foreign defense contractors and modernize its tactical air fleet. The Boramae will replace the ROKAF’s aging fleets of F-4E Phantom II and F-5 fighters, providing a bridge between fourth-generation platforms and the fifth-generation F-35.

While minor discrepancies exist in open-source reporting regarding the specific tail number painted on the first jet, with sources citing both 26-001 and 25-001, all official documentation confirms this airframe as production aircraft No. 001. The successful transition from prototype to production within five years of rollout demonstrates significant maturation in KAI’s manufacturing capabilities and sets a firm foundation for the planned Block II upgrades.

Sources: Republic of Korea Air Force