South Korea is assembling its first serially produced KF-21 Boramae fighter jet. According to South Korean media reports, photos released this week show that work on the first production model of the 4.5-generation multirole fighter is progressing without issue.
Twelve aircraft are already being assembled, and a second production contract covering an additional twenty jets is expected to be signed in June.
The KF-21 is designed to replace the aging F-4 and F-5 fighter fleets while supplementing South Korea’s F-35 inventory. It incorporates low-observable design elements, modern radar and sensor suites, and the ability to integrate a wide range of Western and domestic weapon systems.
As noted by Korea Aerospace Industries (KAI), “the production schedule remains on track,” with the company reaffirming its focus on quality assurance to meet the operational standards required by the Republic of Korea Air Force (ROKAF).
The ROKAF is expected to begin operational testing of the KF-21 in 2026 after completing flight trials and ground evaluations. A total of 120 aircraft are planned for production by 2032.
South Korea will develop three distinct variants of the 4.5-generation KF-21 “Boramae” fighter jet, each tailored for specific missions and operations with the KF-21B variant will be dedicated to Electronic Warfare, the KF-21EX will serve as a Fifth-Generation Fighter, and the KF-21SA is designed for the Export Market.
One of these variants, the KF-21B, will be dedicated to electronic warfare missions. The Electronic Warfare Office (EWO) will be situated behind the pilot in this two-seat aircraft.
The KF-21B electronic warfare aircraft will be equipped with two Electronic Support Measures (ESM) and three Electronic Attack (EA) systems, enabling it to effectively carry out its missions.
It will accompany allied aircraft on missions, primarily focusing on disrupting enemy ground defense systems using jamming technology, similar to the EA-18G Growler operated by the U.S. Navy.
Additionally, the KF-21B may also feature anti-radiation missiles like the AARGM-ER for SEAD (Suppression of Enemy Air Defences) operations.
Another variant, the KF-21EX, is being developed specifically to qualify as a fifth-generation fighter, featuring an Internal Weapon Bay (IWB) to reduce its Radar Cross Section (RCS), making it stealthier and harder for enemy radars to detect.
This variant will be capable of carrying long-range air-to-air “Meteor” missiles or small-sized air-to-ground missiles internally, enhancing its stealth capabilities.
Furthermore, the KF-21 “Boramae” is also being positioned to play a crucial role in the Next Air Combat System (NACS), integrating unmanned aircraft capabilities and satellite data links.
This development aims to elevate the KF-21 into a 5.5-generation fighter, closely approaching the envisioned sixth-generation aircraft sought by various nations, including those in Europe and the United States.
The Republic of Korea Air Force (ROKAF) is reportedly looking to increase the size of the KF-21 fighter, similar to the evolution from the F/A-18 Hornet to the Super Hornet and the F-15 Eagle to the F-15 Strike Eagle.
This modification aims to enlarge the fighter by “several tens of percent.”
The third variant, KF-21SA, is specifically being developed for export customers who will be able to customize their jets with chosen weaponry and electronic systems.
South Korea is expected to begin mass production of the KF-21 this year, with an initial batch of 40 aircraft for the ROKAF.
Launched in 2015, the KF-21 development program is estimated to cost around $6.59 billion.
Korea Aerospace Industries (KAI) plans to deliver 40 KF-21 Block 1 aircraft, designed for air-to-air missions, by 2026, followed by 80 KF-21 Block 2 aircraft for air-to-ground missions in the subsequent phase.
KAI is set to invest approximately $178 million (RM800 million) to commence the construction of the 40 KF-21 “Boramae” aircraft.
The South Korean aerospace giant also aims to start exporting the KF-21 “Boramae” fighter jets to interested customers after fulfilling the requirements of the Republic of Korea Air Force (ROKAF).
“The mass production of the first KF-21 Boramae aircraft is expected to fill the void left by the phasing out of aging fighter jets in the South Korean Air Force,” stated the country’s defense minister in a December announcement.
According to KAI, the engineering and construction phase of the KF-21 fighter aircraft is scheduled to be completed by 2026.
The Korea Times reports that the first KF-21 “Boramae” fighter is expected to be operational with ROKAF by mid-2026.
ROKAF plans to operate up to 120 KF-21 “Boramae” fighters by 2032, replacing its aging F-4 “Phantom” and F-5 fighters still in service. — DSA
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