South Korea’s KF-21 Boramae: A New Era in Global Defence
Only a handful of nations have ever built a supersonic fighter jet from the ground up. South Korea, with its ambitious KF-21 Boramae project, is now on the brink of joining this elite group. Over the past decade, the country has invested billions of dollars and extensive resources to develop a world-class fighter jet. As the project nears completion, the question remains: who will be the first to purchase one?
The first mass-produced KF-21 Boramae, developed jointly with Indonesia since 2015, was unveiled by Korea Aerospace Industries in Sacheon on March 25. This milestone marks a significant step forward for South Korea’s defence industry, which is already among the top 10 arms exporters globally. Analysts believe that the export of the KF-21 could further solidify its position in the global high-end weapons market.
At a recent summit in Seoul, President Lee Jae Myung and Indonesian President Prabowo Subianto agreed to expand cooperation in the defence industry and confirmed that the joint development of the KF-21 is on track to conclude in June. In a joint statement, the two leaders committed to continued collaboration on the jet’s production and pledged joint development of trainer aircraft, anti-tank guided missile systems, and ammunition.
Lee described the KF-21 as a “model example” of international defence cooperation, calling for extending the partnership into naval vessels and air defence systems. Prabowo, on the other hand, emphasized mutual advantage, stating that “Korea possesses outstanding industrial and technological capabilities, while Indonesia has abundant resources and a large market.”
Despite these positive developments, Seoul had hoped to finalize a formal export agreement with Indonesia during the summit. However, financial pressures tied to global instability and inflation reportedly delayed a deal.
The KF-21: A Supersonic Fighter with Advanced Capabilities
The KF-21 is a “4.5-generation” supersonic fighter equipped with advanced radar technology, capable of reaching Mach 1.8 with a maximum range of 2,900km (1,800 miles). Its development places South Korea in an elite tier of nations capable of producing advanced supersonic combat aircraft indigenously, alongside the likes of the United States, China, Russia, Japan, France, and Sweden.
South Korea plans to produce 40 of the Block-1 variants, optimized for air-to-air combat, by 2028, with 20 units completed by 2027 and a further 20 the following year. Indonesia is reportedly considering buying 16 Block-2 aircraft, which add air-to-ground and anti-ship strike capabilities.
South Korean defence exports hit a record US$15.4 billion in 2025, up 60 per cent year on year, according to the Defence Acquisition Programme Administration. Analysts predict exports will soar even higher as global conflicts fuel demand and President Lee pushes for the country to become one of the world’s top four defence exporters by 2030.
However, the KF-21’s development has not been without controversy. Indonesia previously requested a reduction in its financial contribution to the joint project, which has also been overshadowed by allegations of technology leaks involving Indonesian engineers. Last year, the two countries reached a revised cost-sharing agreement, lowering Jakarta’s contribution from 1.5 trillion won (US$994 million) to 600 billion won, of which 500 billion won has been paid.
Expanding Markets and Strategic Alliances
Analysts stress the importance of Indonesia’s participation in the project both as a vehicle for technology transfer and the long-term development of the Southeast Asian nation’s own defence industrial base. Kim Mi-jung, a senior researcher at the Korea Institute for Industrial Economics and Trade think tank, said the programme could strengthen cooperation between South Korea and countries across Southeast Asia, particularly in air and naval surveillance.
An Indonesian order for the jets might also catalyse interest from the Philippines, Thailand, and other Southeast Asian nations, Professor Jang said. Middle Eastern nations including the UAE and Saudi Arabia have also expressed interest in acquiring the aircraft, broadening the KF-21’s potential market.
South Korea and Indonesia’s defence ties date back decades, with Jakarta having previously imported Korean-made trainer aircraft, landing ships, and submarines—purchases analysts credit with establishing Seoul’s credibility as a serious defence supplier.
Beyond Defence: Strengthening Economic Ties
Wednesday’s summit made clear that both governments recognize the significance of their broader relationship. Lee highlighted Indonesia’s importance as a supplier of liquefied natural gas and coal, and called for deeper cooperation in shipbuilding, artificial intelligence, and electric vehicles. Both leaders also reaffirmed their commitment to building out Indonesia’s EV ecosystem, including battery production, recycling, and supply chain development.
South Korea exported US$7 billion worth of goods to Indonesia last year while importing US$11.3 billion, according to trade data. The two countries have operated under a free-trade agreement since 2020, with trade flows anchored by Indonesian raw materials and South Korean semiconductors and machinery.
“Amid a rapidly shifting global and regional order, economic cooperation between the two countries is becoming increasingly important,” said Lee Jae-hyon, a principal fellow at the Asan Institute for Policy Studies in Seoul who specializes in Southeast Asian politics and international relations. He pointed to Indonesia’s energy resources, in particular, given the ongoing instability along key Middle East shipping routes amid the US-Israel war on Iran.
As the KF-21 moved from development into deployment, both nations appeared poised “to turn a complex partnership into a long-term strategic asset,” Lee added.
