The KF-21 is no longer a project and is one step away from operational service
South Korea has been trying for a quarter of a century to turn a political ambition into a fighter jet manufactured under its own direction. What we are seeing now is the moment in which this journey begins to materialize: the first production KF-21 has already left the factoryhas flown and It is scheduled for delivery to the Air Force in September. That does not mean that the entire fleet will be fully operational from that day, but it does mean that the Boramae has left the prototypes behind to begin its incorporation into military service. The succession of milestones in recent months explains this change in stage. KAI introduced the first production unit on March 25 and flew it on April 15, before the program passed final combat fitness evaluation on May 7. A little over a month later, June 15the initial type certification arrived, which certifies compliance with government airworthiness and flight safety requirements. The next step will be the formal acceptance of the device and its delivery to the South Korean operator. The project that would end up becoming the KF-21 began to take shape in March 2001when then-President Kim Dae-jung expressed ambitions to develop an advanced fighter of his own. The initiative, however, took years to overcome feasibility studies and debates about its cost. The industrial leap arrived in December 2015when the procurement agency DAPA signed the system development contract with KAI. Indonesia joined as a partner and initially assumed about 20% of the cost, in exchange for technology, industrial participation and local production capacity. That distribution began to break down when Indonesia accumulated delays in its financial contributions. After several renegotiations, both governments agreed in June 2025 to reduce its contribution to about 600 billion won, about a third of the original commitment, and also limit the technology it would receive. The withdrawal of local co-production was made public in April 2026 and confirmed by Indonesian authorities in June. Jakarta is still studying the purchase of a smaller number of aircraft completed in South Korea, although there is no final order yet. Converting the KF-21 into a fleet has required two large pools of investment. The first, of about 8.8 trillion won, equivalent to approximately 5.24 billion euros at the exchange rate on July 24, 2026, corresponds to the development of the plane. The second, estimated at 7.92 trillion won, nearly 4.72 billion euros, includes the initial plan to acquire 40 unitsits weapons and other associated costs until 2028. This item does not offer a clean price per device, because it also includes engines, training, spare parts, documentation and logistical assistance. What the South Korean Air Force will receive is a 4.5-generation twin-engine fighter, not a fifth-generation stealth aircraft comparable to the F-35. The KF-21 can reach approximately Mach 1.8 and transport up to 7.7 tons of weaponsin addition to integrate an AESA radaran IRST infrared sensor and electronic warfare systems. The first units will belong to Block I, a configuration focused mainly on air-to-air missions. Broader air-to-ground and air-to-surface capabilities will come with the further evolution of the program. The industrial leap is best understood when we look at who is actually building the aircraft. The South Korean KAI leads the design, integration and assembly, while its compatriots Hanwha Systems and LIG Nex1 provide, respectively, the AESA radar, part of the avionics, electronic warfare and weapons management. Hanwha Aerospace, also South Korean, Assembles in Korea and produces components under license for the F414-400K engines from the American GE Aerospace. Since the first flight of the prototype on July 19, 2022, the six test aircraft have completed around 1,600 flights and around 13,000 test conditions without accidents. The arrival of the KF-21 does not mean that South Korea will do without foreign fighters either. Seoul has ordered another 20 US F-35Aswhich will begin to arrive from 2027, and a fleet made up of platforms of different origins and functions will continue to operate. The change is elsewhere: the country can now lead the design, production, maintenance and much of the future improvements of its own combat aircraft. When the first installment is completed, the Boramae will not have eliminated external dependence, but it will have tangibly reduced its limits. Images | Government of Korea/Ministry of Defense In Xataka | Airbus has made a revolutionary bet for its business model: manufacturing the hydrogen engines of the future