Can South Korea’s most advanced fighter jet KF-21 compete with China, US and Europe?

A model of the KF-21 Boramae fighter on display at ADEX 2025, Oct. 21, 2025 / Captured from Seoul ADEX's Facebook

South Korea’s first home-grown combat aircraft, the KF-21, still has a “long way to go” competing globally against products from the US, Europe and China, analysts say, as the fighter jet is finally rolled out.

In March, Korea Aerospace Industries (KAI) officially unveiled the first production unit of the KF-21 Boramae, making South Korea the eighth country to join an elite group capable of indigenously developing advanced supersonic combat aircraft.

The roll-out marked the start of mass production for the 4.5-generation fighter, with an initial 40 Block I units to be completed for the South Korean Air Force by 2028.

According to Bence Nemeth, a senior lecturer in defence studies at King’s College London and executive director of the King’s Centre for Defence Economics and Management, the KF-21 could be competitive in overseas exports but entered the market “late and in a crowded field.”

Nemeth said South Korea’s advantages were likely to be its cost, quality, delivery speed and willingness to offer industrial cooperation. But he added that procuring fighters was also about political alignment and wartime supply chain reliability.

“The KF-21 will therefore need aggressive marketing and credible long-term sustainment guarantees,” Nemeth argued.

“A stealthier version of the KF-21 could compete more directly with fifth-generation aircraft, but that remains dependent on future upgrades, marketing and political ties between Seoul and potential markets.”

South Korea has been trying to boost exports of the KF-21 to reduce per-unit cost and possibly compete with 4.5-generation counterparts in China, the US and Europe.

Apart from the United States and China, the other countries in the now eight-strong elite group are Russia, France, Sweden, India and Japan.

Indonesia, which co-produces the KF-21, is reportedly considering buying 16 Block II aircraft, with Seoul in April agreeing to send its demonstrator to the country.

However, the project has sparked controversy after Jakarta requested a reduction of its financial contribution.

Last year, the two countries reached a revised cost-sharing agreement, significantly lowering Jakarta’s contribution from 1.5 trillion won ($1.01 million) to 600 billion won, primarily shifting the financial burden to Seoul and potentially increasing the unit cost of the aircraft.

President Lee Jae Myung speaks during an event to celebrate the first delivery of the KF-21 figher jet produced by Korea Aerospace Industries at the firm's headquarters in Sacheon, South Gyeongsang Province, March 25. Joint Press Corps

Yang Uk, research fellow and director at The Asan Institute for Policy Studies’ Centre for Foreign Policy and National Security in Seoul, said a number of countries would be interested in operating the KF-21 because of its cost-effectiveness but that the lack of a combat record remained a limitation.

“Discussions can only begin once Block II is completed. Basically, its performance hasn’t reached 100 percent yet,” Yang explained.

“The initial [Block I] only secures air-to-air capabilities,” he continued. “It needs to reach Block II first, starting with ground attack capabilities for these functions to be integrated to a certain extent before it can be evaluated as an aircraft capable of performing full-scale operations.”

Kim Ki-won, a professor at Daekyung University’s department of military studies, said Seoul must first aim to strengthen its own air force’s capabilities to respond to multiple aerial threats by developing autonomous technology for its manned-unmanned teaming (MUM-T) system.

A MUM-T system is a collaborative operational framework in which human-operated platforms like fighter jets and autonomous ones like drones work together as a single synchronised unit.

Kim said aerial threats in particular — such as North Korean missiles and drones, and Chinese fighter jets and drones — were “becoming increasingly severe with both quantitative and qualitative enhancements evolving at a leapfrog pace.”

“If such empirical results for manned-unmanned hybrid systems are obtained, a niche market will open up, targeting countries facing threats on air defence from air power powerhouses,” he added.

Choi Gi-il, professor of military studies at Sangji University, described the KF-21’s development as not yet complete and that it had a “long way to go” to be compared with its 4.5-generation counterparts like the Chinese-made J-10C and the French-made Rafale.

“Although research on the MUM-T has already commenced and significant progress has been made, it appears that the transition to a sixth-generation fighter will take a considerable amount of time,” Choi said.

First announced in 2001 and formally launched as a development project in 2015, the first series-production unit of the KF-21 marks the quarter-century culmination of Seoul’s effort to field an indigenous fighter jet, which is scheduled to replace the Republic of Korea Air Force’s ageing F-4 and F-5 fleets.

Block I aircraft focus on air superiority missions, equipped with beyond-visual-range Meteor and short-range IRIS-T air-to-air missiles.

Meanwhile, Block II upgrades are likely to feature full air-to-ground and air-to-ship mission capability, with completion scheduled for early next year.

Block III is likely to enter the fifth-generation model with full stealth capabilities by adding internal weapons bays and could add sixth-generation features such as MUM-T, with drone wingmen flying alongside. It is scheduled for completion in the 2030s.

Kim said the KF-21 could achieve overwhelming air superiority and secure a sufficient amount of “kill chain” forces to provide a credible deterrent against North Korean threats, while narrowing the gap with China’s superior numbers in the West Sea.

He noted that the KF-21 could ensure a steady supply of weaponry and reduce reliance on foreign military support, granting Seoul “more flexible” operational execution.

“Unlike surface-to-surface and ship-to-surface missiles, air-to-air missiles can provide sufficient quantities for striking the origin point, allowing for effective attacks when multiple targets are generated,” Kim added.

He also said South Korea had sufficient technological capabilities to autonomously upgrade the KF-21 to a fifth-generation fighter jet.

Read the article at SCMP.