Second Prototype of South Korea’s KF-21 Stealth Fighter Makes First Flight: A Promising Future Ahead

On November 10 the second prototype of the South Korean KF-21 Boramae fifth generation fighter made its first flight from a Korea Aerospace Industries’ facility near Sacheon Airport. The fighter spent 35 minutes in the air, and was flown by a pilot from the Air Force’s 3rd Flight Training Wing. The flight took place less than four months after the first prototype first took to the air on July 19, with the two aircraft being distinguishable from one another by the newer model’s darker paint scheme. The South Korean defence procurement agency, the Defense Acquisition Program Administration, announced regarding the latest flight: “Following the success of Unit 2’s first flight, the Korean-made fighter is expected to conduct flight tests with two aircraft… After completing preparations for ground tests and flight tests, Prototype Units 3 to 6 are scheduled to begin flight tests sequentially from the end of December ’22 to the first half of ’23.” 

The KF-21 is expected to produce a fifth generation fighter for operational service by 2027, although some sources have dubbed it a ‘fifth minus (5 minus)’ fighter due to its much more limited capabilities compared to rivals such as the American F-35 and Chinese J-20 and FC-31. This includes use of fourth generation F414 engines, a lack of supercruise capabilities, relatively conservative stealth features, and a lack of external weapons carriage for earlier variants. The aircraft’s maintenance needs and operational costs are nevertheless expected to be far lower than those of the F-35, making it more viable to field a much larger fleet, while its weapons and avionics will be on par with fifth generation fighters. The aircraft will come at a comparable and likely significantly lower price to ‘4+ generation’ fighters such as the F-18E/F, French Rafale and pan-European Eurofighter, while being significantly more capable.

Currently only two fifth generation fighters are both in production and fielded at squadron level strength anywhere in the world – the Chinese J-20 and the American F-35. They are expected to be joined by China’s FC-31 and Russia’s Su-57 around 2024, when both are expected to form their first full squadrons. As a NATO compatible asset, the KF-21 is likely to see major sales to U.S.-aligned states and deeply undercut the market shares of European producers, mirroring the success of Korea’s competitive tanks, artillery and trainer jets in European markets over Europe and America’s own products despite political pressure from Western suppliers on potential clients.