The KF-21 Boromae, Explained: Korean Aerospace Industries (KAI) have made a name for themselves by developing, testing, building, and exporting a supersonic combat aircraft within a relatively short time for any nation attempting to take on this challenge. That aircraft, the two-seat FA-50, has been an unqualified success and has even been acquired by NATO-member Poland.
This program was developed in cooperation with Lockheed Martin, so the aircraft resembles a slightly scaled-down F-16. KAI has ambitious plans for this aircraft, including developing a single-seat version that frees up the space and weight taken by the second seat, for more fuel and weapons.
“This [single-seat] aircraft would cost considerably less than an F-16 but would have 80 percent of the American aircraft’s capability and performance,” said KAI representatives that 19FortyFive spoke with in Malaysia in 2023.
However, the plans for this aircraft were sidelined temporarily in favor of a higher-priority program, the KF-21 Boromae. This aircraft externally appears to be similar to the United States F-35, but powered by two GE F414 jet engines, the same power plant installed in the Boeing F/A-18 E/F Super Hornet.
KAI Ambitions with: KF-21 Boromae
The KF-21 is an advanced design, but it is not a 5th-generation aircraft in the class of the F-35 or F-22A. The aircraft’s original design does not include an internal weapons bay, which is one of the reasons that, in its current configuration, it is regarded as a 4.5-generation design.
Most other attributes associated with 5th-generation fighters are part of the KF-21 design. These include an Active Electronically-Scanning Array (AESA) radar set developed in South Korea. It also has design characteristics, such as a blended-body shape, that are frequently associated with stealth aircraft.
KAI officials now say they are reviving the F-50 single-seat aircraft and will be marketing it as part of a corporate-wide strategic initiative called “Global KAI 2050 – Beyond Aerospace.” The company representatives state that the company’s overall goal is to make the company the seventh-largest aerospace firm in the world.
This long-range plan was launched in parallel with KAI’s efforts to reduce its dependence on Korean government sales and increase exports of its products. Previous company statements have called for a two-stage process in which FA-50s are first custom-configured to different nations’ individual requirements.
A Two-Staged Sales Strategy
KAI states that they will be initially approaching nations still operating legacy platforms like older Mikoyan and Sukhoi models, the US F-5, A-37, A-4, France’s Alpha Jet, and the Czech L-39 to sell them on the FA-50 as a combination training and combat/attack platform. If a customer then acquires the KAI jet, this will lay the groundwork for the company to make a pitch for a follow-on procurement of the KF-21.
KF-21 is, of course, the second step in these KAI ambitions of becoming another of the world’s fighter export powerhouses. The aircraft’s production program is highly ambitious, with the ROKAF to receive 40 of the aircraft by 2028, followed by another 80 airframes by 2032. The potential export orders mean the Korean firm’s production lines will be in high gear.
KAI’s is for series production of the KF-21 to begin in 2026 and to have EMD completed in the same year. South Korean’s Defense Acquisition Program Administration (DAPA) has designated February 2026 as a target date for series production of Block 1 aircraft.
In the meantime, there are options for integrating what are being called “5th-generation capabilities” into later Block series of the aircraft. These include modifications that will further reduce the radar cross-section and enclose the weapons carriages on the underside of the aircraft to create an internal weapons bay. South Korean defense firm Hanwha is also working on the development of a next-generation engine to replace the American F414.
Future Growth
Having already signed for 36 of the FA-50s, Poland becomes one of the first potential buyers of the KF-21. As far back as 2023, executives from the state-run Polish Armaments Group (PGZ) have shown interest in procuring the aircraft. The Poles are expected to decide whether or not to commit to the KF-21 no later than 2026.
PGZ sources previously told the Polish news outlet Defence24, “It is possible that in the future that … an industrial cooperation in the area of development and production of the KF-21 Boramae, where the natural partner for KAI Ltd. would be, among others, Wojskowe Zakłady Lotnicze (Military Aviation Plant) Nr 2 in Bydgoszcz. This is the lead [enterprise] of aviation trade in Poland, that already has experience in maintenance and restoration of F-16s and the C-130 Hercules.”
KF-21 screenshot from first flight. Image Credit: YouTube Screenshot.
KAI had already been engaged in test flights of their fifth single-seat KF-21 prototype as far back as May 2023. This aircraft has since become the primary test platform for avionics performance verification, including the AESA radar. This same prototype was later pressed into service to conduct air-to-air refueling tests.
Weapons testing began in 2023 with the active-homing MBDA Meteor test firings and the Diehl IRIS-T IR-guided AAM. MBDA officials have stated that KAI were evaluating these two missiles plus the IR-guided ASRAAM in the first weapon tests for KF-21, describing KAI’s approach to testing and validation as “very aggressive”.
“KAI conducted a Meteor launch as one of the firings for the very first test flight of one of the program prototypes, which is almost unheard of,” said a company representative.
The ROKAF is expected to procure at least 160 aircraft, with a per-unit cost projected at US $80-100 million. The biggest selling point for the KF-21, say KAI, is that their aircraft can become an affordable replacement for F-16s and other fourth-generation models that offer 5th-generation data connectivity and performance—but at a price well below other options.
KF-21 Fighter. Image Credit: Screenshot.
“We see the KF-21 as the most cost-effective and best-suited replacement for the F-16 and one which will fill the slot that many had in the past expected to be taken by the F-35,” said a KAI spokesman.
About the Author: Reuben F. Johnson
Reuben F. Johnson is a survivor of the February 2022 Russian invasion of Ukraine and is now an Expert on Foreign Military Affairs with the Fundacja im. Kazimierza Pułaskiego in Warsaw. He has been a consultant to the Pentagon, several NATO governments and the Australian government in the fields of defense technology and weapon systems design. Over the past 30 years he has resided in and reported from Russia, Ukraine, Poland, Brazil, the People’s Republic of China and Australia.
