South Korea marked a pivotal step in its journey to military aviation independence on May 20, 2025, as Korea Aerospace Industries (KAI) and the Defense Acquisition Program Administration (DAPA) jointly announced the beginning of the final assembly phase of the first production KF-21 Boramae multirole fighter. The milestone event was celebrated at KAI’s headquarters in Sacheon, where the nation’s first domestically developed fighter jet is now taking shape in earnest.
The announcement marks a significant leap for South Korea’s decade-long effort to build a next-generation fighter jet capable of modern aerial combat and multirole operations. The KF-21 program, initiated in 2015, is one of the most ambitious defense projects in the country’s history, aimed at replacing the Republic of Korea Air Force’s (ROKAF) aging fleet of F-4 Phantom and F-5 Tiger II fighters.
Jeong Gyu-heon, head of DAPA’s Future Power business division, praised the engineers and project teams that have brought the Boramae to the final assembly stage. “It is thanks to the dedicated efforts of our researchers and developers that we have reached this historic moment,” he said. “The KF-21 represents the future of the Republic of Korea Air Force.”
Although DAPA did not provide a specific completion date for the aircraft, it confirmed that the first KF-21 is scheduled for delivery to the ROKAF in 2026. Before this, the aircraft will undergo rigorous acceptance test flights.
The fighter in assembly is part of a 20-aircraft batch secured under a contract signed between KAI and DAPA in June 2024. This initial deal, valued at 1.96 trillion won (approximately US$1.41 billion), initiated mass production in July 2024. As of the May announcement, 12 additional aircraft are reportedly in various stages of assembly.
The KF-21 Boramae (“Hawk” in Korean) is categorized as a 4.5-generation fighter aircraft, integrating stealth features, digital avionics, and multirole capability. Although not fully stealth like the American F-35, it is seen as a cost-effective and highly capable alternative.
Powered by two General Electric F414-GE-400K engines, the KF-21 can reach a top speed of Mach 1.81 and has a maximum thrust of 44,000 pounds. It carries a maximum payload of 17,000 pounds and boasts a ferry range of 1,550 nautical miles. Designed for both air superiority and precision ground attack missions, the KF-21 is intended to enhance South Korea’s combat readiness well into the 2030s.
Structurally, the aircraft has been noted for its resemblance to the U.S.-made F-22 Raptor, sharing similar twin-tail, fuselage contouring, and air intake designs. The prototype even features a conformal gun pod mounted above the left air intake, reminiscent of the F-35A.
More than 65% of the KF-21’s components are manufactured domestically, including an indigenous Active Electronically Scanned Array (AESA) radar. Developed by Hanwha Systems, the radar was validated aboard a modified Boeing 737-500.
In terms of armament, the KF-21 will be compatible with a mix of Western weaponry, including the European-made Meteor Beyond Visual Range Air-to-Air Missile (BVRAAM), the IRIS-T short-range air-to-air missile, and potentially the Taurus KEPD 350 air-launched cruise missile in later variants.
South Korea unveiled the first prototype of the KF-21 on April 9, 2021. The jet made its maiden flight from Sacheon Airport on July 19, 2022, following months of taxi testing. A total of six prototypes—four single-seat and two twin-seat variants—are part of an extended flight testing campaign expected to continue through 2026.
This structured test campaign is a critical stage in validating the aircraft’s performance, avionics, radar, and weapon integration before final delivery to the ROKAF. So far, the aircraft has logged hundreds of test flights, gradually expanding its flight envelope and validating performance benchmarks.
Indonesia signed on as a development partner in 2014, committing to 20% of the total program cost, which was originally estimated at 7.5 trillion won (US$6.3 billion). However, Jakarta’s contributions have been inconsistent, leading to renegotiations starting in 2018.
After several delays and diplomatic back-and-forth, Indonesia resumed partial payments in 2022. In 2024, South Korea approved a revised agreement to lower Indonesia’s share to 600 billion won (approximately $409 million). Despite earlier plans to acquire 50 KF-21s, Jakarta’s current procurement intentions remain ambiguous.
Tensions were further strained in 2024 when two Indonesian engineers were caught attempting to smuggle unauthorized flash drives from KAI’s facilities. While a joint investigation by DAPA, South Korea’s National Intelligence Service, and military counterintelligence found no classified information was compromised, the incident underlined the complexities of international defense collaborations.
Despite setbacks, both nations reaffirmed their commitment to the KF-21 program in early 2025. The partnership remains a cornerstone of South Korea’s vision to become a global player in advanced defense technologies.
KAI and DAPA are actively marketing the KF-21 to potential international customers. The Philippines and Peru have been mentioned as target buyers, while the United Arab Emirates has signed a cooperation agreement that grants it observer status during the aircraft’s operational rollout in the ROKAF.
For South Korea, securing foreign sales is vital not only to recoup development costs but also to position the KF-21 as a legitimate player in the competitive fighter aircraft market. With a price tag significantly lower than the F-35 and a design focused on operational versatility, the KF-21 could appeal to countries looking to modernize their air forces without breaking their defense budgets.
The KF-21 program is more than a fighter jet development; it is a statement of South Korea’s intent to rise as a defense manufacturing powerhouse. It demonstrates the country’s growing capacity to independently design, test, and field high-end military technologies.
With its eyes set on delivering 120 aircraft to the ROKAF by 2032, the successful completion of the first production jet and its subsequent acceptance tests in 2026 will set the tone for the program’s long-term viability. It will also serve as a litmus test for whether South Korea can transition from licensed defense production to full-spectrum indigenous capability.
The KF-21’s entry into service will significantly enhance the ROKAF’s ability to respond to regional threats, especially amid rising tensions with North Korea and strategic competition in the Indo-Pacific. It represents not only a leap in capability but also an assertion of South Korea’s sovereign defense posture in an increasingly uncertain global security environment.
As the first production KF-21 fighter moves through final assembly, South Korea stands on the cusp of achieving a generational transformation in air power. The successful delivery of this aircraft in 2026 will not only mark a technological achievement but will also open doors to expanded international cooperation, defense exports, and enhanced national security.
