In April, South Korea unveiled the first prototype of its new indigenously produced fighter, more than five years after the KF-X was first announced. Dubbed the KF-21 Boramae, the country has hailed the aircraft as a major victory for South Korea’s domestic aviation industry and as a sign of the country’s growing self-sufficiency in the defense industry, with South Korean President Moon Jae-in describing the KF-21 as representing a “new era of independent defense” and a “historic milestone in the development of the [South Korean] aviation industry”.
South Korea is planning to produce six prototypes of the KF-21, with the first three slated to be completed by the end of this year and the remaining three expected in the first half of next year. Following ground and flight testing, production of the KF-21 will begin with South Korea looking to deploy 40 aircraft by 2028 and an additional 80 by 2032.
The most likely short-term role for the KF-21 is as a replacement for some of South Korea’s aging and outdated fighter aircraft. The Republic of Korea Air Force (ROKAF) is comprised of a blend of high- and low-end aircraft. South Korea made an initial purchase of 40 F-35As, and has since decided to purchase an additional 20 of the fifth-generation stealth aircraft. These will operate alongside the ROKAF’s fleet of fourth-generation fighters that includes 61 F-15K “Slam Eagles” and 169 F-16C/D fighters, as well as its almost 160 older F-5 and F-4 aircraft. The KF-21 is likely to replace many of these older aircraft which, given the higher operating cost of the newer fighter, may result in a quantitative decrease for the ROKAF that will be offset by a significant qualitative boost.
The KF-21 is also likely to be an attractive system for export. South Korea has extensive experience exporting combat aircraft, with its fourth-generation T-50 aircraft having seen combat following its sale to a number of countries such as Iraq and the Philippines. The KF-21 may well be marketed to these countries, as well as others such as Thailand that operate the T-50 along with either F-16s and F-5s, aircraft slated to be replaced in South Korea by the KF-21. India could be an option as well, given the growing defense ties between the two countries.
The KF-21 was developed as a joint project between South Korea and Indonesia, with the former owning 80 percent of the shares of the program. Indonesia has reportedly fallen behind on payments related to the program, though the Indonesian defense minister was present at the unveiling ceremony.
Despite its description as an indigenously produced aircraft, some important systems are still foreign in origin, including the American GE F414 engines and a mix of U.S. and European weapons systems. Still, about 65 percent of the aircraft’s components are South Korean origin, including the KF-21’s active electronically scanned array radar, electronic warfare suite, infrared search-and-track pod, and electrooptical targeting pod.
The KF-21 is likely to be a very capable combat aircraft. The Boramae boasts a maximum takeoff weight of 25,600 kilograms, and is being designed with ten pods for air-to-air missiles and other weapons. The KF-21 will reportedly have a maximum speed of Mach 1.8 and a cruising distance of almost 3,000 kilometers. The aircrafts indigenously produced AESA radar comes with a module of some 1,088 modules with a beam-steering angle of 60-70 degrees, while the number of transmitters is likely to grow to 1,300 at some point in the future.
The KF-21 has been described as a generation 4.5 aircraft, demonstrating capabilities likely in excess of many fourth-generation aircraft but lacking the full stealth capabilities that characterize advanced fifth-generation aircraft such as the F-35 and F-22. The KF-21 does possess some stealth capability, with a radar cross section comparable to that of the Eurofighter Typhoon, with the potential for upgrades in the future that could increase the Boramae’s stealth capabilities. Most notably, the KF-21 has been designed with external weapon hardpoints. While most advanced stealth aircraft house their weapons internally, the external weapon mounting on the KF-21 has helped to reduce the cost and complexity of the aircraft. The KF-21 may, however, have been designed in such a way as to support internal weapons housing in the future.
In all, the KF-21 provides South Korea with a relatively cost-effective means for qualitative improvement of its Air Force, while also highlighting the growing independence of the country’s defense industry. The KF-21 could also emerge as an attractive option for those country’s searching for a more accessible option than the F-35 and as an alternative to Chinese origin aircraft.