South Korea is zooming ahead with the mass production of its KF-21 fighter jet, and China won’t be happy

DAPA plans to contract the first 20 units of KF-21 this year, while the remaining 20 units will be contracted by February next year after completing performance verification tests by June, which will include the jets’ connectivity with air-to-air missiles and active electronically scanned array (AESA) radar capabilities.

The South Korean arms procurement agency stressed that securing fighter aircraft that met “the future battlefield operation concept” was essential following the retirement of older operational fighter jets.

“Through this project, it is expected to contribute to strengthening the air force’s base power by preventing a power vacuum caused by ageing, long-term operational fighters and securing Korean aircraft capable of performing cooperative operations with cutting-edge fighters,” DAPA said in a statement last week.

01:20

South Korea’s first home-grown fighter jet completes maiden test flight

Developed by Korea Aerospace Industries (KAI) and co-produced with Indonesia, the KF-21 is South Korea’s first fully home-grown fighter jet. The supersonic fighter jet project began in 2015 to replace the air force’s ageing fleet of F-4 and F-5 jets.

The South Korean Air Force is expected to receive its first KF-21, dubbed Block-1, in the second half of 2026. Seoul is also aiming to develop KF-21 Block-2 with upgraded air-to-ground attack capabilities by 2028, producing and deploying 120 units in total by 2032.

While the KF-21 currently has limited stealth capabilities, KAI reportedly plans to develop Block-3 by the early 2030s, upgrading the aircraft into fifth-generation or even 5.5-generation fighters with further stealth capabilities and internal weapons bays.

“The KF-21 is a fighter capable of responding to a wide spectrum of aerial threats, including fifth-generation fighters, based on its unique network operation capabilities,” Yang Uk, a research fellow at the Asan Institute for Policy Studies in Seoul, said.

“Although it is known as a 4.5-generation fighter, it is actually a fifth-generation design model and will play an active role as a force multiplier as it will emphasise not only stealth but also network capabilities that can carry out AI-MUMT [artificial intelligence manned-unmanned teaming] operations with various autonomous weapon systems,” he said.

China, of course, is not going to be happy

Bruce Bennett

Bruce Bennett, a defence researcher at the US-based think tank Rand Corporation, said it was likely that China would not be pleased by the addition of the KF-21 to Seoul’s F-35 fleet.

“China, of course, is not going to be happy,” Bennett said.

He pointed out that Seoul’s upgraded air force would “provide capabilities to deal with Chinese fighter aircraft threats and to clearly dominate over [North Korea]”.

Harry Boneham, a senior analyst at global military intelligence company Janes, said it was Beijing’s own military modernisation that drove its rival to retain the qualitative edge. He also noted the KF-21 could be “part of an effective strategy in countering Chinese air power”.

“Its adoption into the South Korean Air Force will certainly enhance its combat air potential,” Boneham said. “The presence of a more capable air force in a nearby rival is likely to be a factor which [Beijing] will consider.”

Yoon Suk-joon, a visiting research fellow at the Korea Institute for Military Affairs and specialist in Chinese weapons systems, echoed the view, saying the KF-21 will “show air superiority compared to J-10, J-11 and J-16”.

The South Korean jet is thought to have similar characteristics to China’s FC-31, Shenyang Aircraft Corporation’s carrier-based fifth-generation fighter jet currently under development, signalling a possible competition between the two aircraft in the global arms market.

China’s FC-31 is thought to share similarities with South Korea’s KF-21. Photo: Handout

Since the developmental phase, both models have been aimed at overseas export, with a similar maximum speed of up to Mach 1.8.

“The two aircraft will be superior to fourth-generation aircraft such as the F-16, with superior avionics, some stealth and power,” Timothy Heath, a senior international defence researcher at Rand Corporation, said.

“In many other respects the two planes share similar characteristics. They will be multi-role aircraft that have AESA radars, twin engines, stealth coatings and similar payloads.”

South Korea has signed a deal to provide 50 units of KF-21 to its joint development partner Indonesia, while other countries, such as the Philippines and Poland, have also shown an interest in the jet.

China displays FC-31 fighter model at Saudi defence show amid Mideast conflicts

If the two countries do pit their fighter jets against each other on the export market, the Middle East is likely to be the main competition arena.

Riyadh has also shown interest in Seoul’s sixth-generation fighter jet development project, dubbed KF-XX, with KF-21 as its basis, according to South Korean defence minister Shin Won-sik after his visit to Saudi Arabia in February.

“Naturally, exports of the KF-21 will be more dominant,” Yang said. “It is attractive in that it is a non-American weapon system that follows Nato standards.”

Heath said South Korea has the potential to export the KF-21 to countries attracted by the prospect of an advanced fighter that costs much less than the F-35 and is easier to acquire.

“China is likely to view the upgrade primarily as a threat to its own export ambitions of fighter aircraft,” Heath said.

01:49

Chinese floating barrier blocks entrance to Philippine ships at South China Sea flashpoint

“Export of the aircraft to countries like … [the] Philippines could raise tensions between China and South Korea,” he added, referring to ongoing disputes between Beijing and Manila in the South China Sea.

Manila, which is already using South Korea’s FA-50 fighter jet, is reportedly thinking of buying the KF-21.

Boneham said the F-35 is only conditionally granted to US allies, and Beijing imposed an export ban on its J-20, leaving a relative scarcity of advanced 4.5-generation and fifth-generation fighters on the market.

It is a situation that will only add to the demand for new arrivals like the KF-21 and FC-31.

“China has enjoyed relative success in markets such as Africa and the Middle East. There are likely customers in these regions looking for a more affordable [and] accessible alternative to the F-35, and the FC-31 may be the answer for them,” Boneham said.

South China Morning Post