Is the Landscape of Sixth-Generation Fighter Development Changing? [Yang Nakgyu's Defence Club]

Seismic shifts by country over independent vs. joint development
France puts the brakes on Europe's joint development program

The landscape of sixth-generation fighter jet development is changing. Differences of opinion are clashing among joint development countries, and even the states that have embarked on development are shifting their focus from airframe performance to artificial intelligence (AI) and manned-unmanned teaming, signaling a change in development trends.

Henrik Ron, head of Saab Korea, is holding and explaining a model of the Gripen, a lightweight single-engine supersonic multi-role fighter developed by Saab AB. Photo by Yoon Dongju

FCAS facing bankruptcy crisis over France's demand for a larger stake

The leading countries that fired the starting gun for the joint development of a sixth-generation fighter are France, Germany, and Spain. These countries are pursuing the Future Combat Air System (FCAS). FCAS is a manned-unmanned integrated weapon system that includes a sixth-generation fighter, combat drones, and a combat cloud. It is the largest weapons project in European history, with total program costs estimated at more than 100 billion euros (about 173 trillion won). In 2017, French President Emmanuel Macron and then German Chancellor Angela Merkel agreed to aim for operational deployment in 2040, and Spain later joined the project.

It is France that has slammed on the brakes, insisting on increasing its stake. The argument is that France should receive a larger share because Dassault, the French participant, is effectively responsible for design and key components. Back in the 1980s, during discussions on the development of the Eurofighter Typhoon, France temporarily took part in talks with the United Kingdom, Germany, Italy, and Spain, but eventually went on to independently produce the Rafale fighter. As a result, Germany has decided to seriously explore cooperation with other countries. Options under consideration include partnering with Saab, the Swedish defense company that produces the Gripen fighter, or joining the United Kingdom, Italy, and Japan in the Global Combat Air Programme (GCAP).

Italian Prime Minister Giorgia Meloni and German opposition leader Friedrich Merz are reported to have discussed the possibility of Germany joining GCAP during talks last month. Saab Chief Executive Officer (CEO) Micael Johansson said in an interview with a German media outlet in December 2025, "If the two governments express a clear political will, we are ready to jointly develop a fighter with Germany."

Saudi Arabia left out in the cold

Saudi Arabia has so far failed to find partners for the joint development of a sixth-generation fighter. The United Kingdom, Italy, and Japan signed a treaty last month on the Global Combat Air Programme (GCAP) to jointly develop a sixth-generation fighter. GCAP plans to deploy fighters with greatly enhanced supersonic performance and radar detection capabilities into actual combat by 2035. Saudi Arabia has repeatedly expressed its desire to participate in GCAP. Crown Prince and Prime Minister Mohammed bin Salman Al Saud even conveyed this wish in person when he met with Japanese Prime Minister Fumio Kishida. However, Japan is reported to have opposed the idea, citing that much of the work has already been completed and that the schedule to complete the project by 2035 is already very tight.

U.S. and China dominate next-generation fighter development

The United States is pursuing the Next Generation Air Dominance (NGAD) program to develop a sixth-generation fighter. The U.S. Air Force has selected Boeing's F-47 to replace the F-22 stealth fighter. A prototype is currently being built with the goal of operational deployment in the 2030s, and the first test flight is planned for 2028. Going forward, the United States also plans to focus on the development of Collaborative Combat Aircraft (CCA), which will include unmanned combat aircraft.

The U.S. Navy is running a separate program from the Air Force. This is the F/A-XX next-generation carrier-based aircraft program, which will be responsible for the future of carrier strike groups. Boeing and Northrop Grumman have joined the competition for the contract. The F/A-XX program aims to develop a sixth-generation fighter that will serve as the mainstay of the U.S. Navy in the 2040s. This aircraft, which must replace the current mainstay F/A-18E/F Super Hornet, is different in nature from the U.S. Air Force (USAF) next-generation fighter. The sixth-generation carrier-based aircraft, which will also replace electronic warfare aircraft, is expected to be operated from aircraft carriers alongside the F-35C.

China's next-generation fighter to counter the United States

China plans to develop a sixth-generation fighter while simultaneously building up its fleet of fifth-generation fighters. The Royal United Services Institute (RUSI), a British think tank, has analyzed that by 2030 there is a possibility that around 1,000 fifth-generation J-20s (including the J-20A and J-20S) and about 900 4.5-generation J-16s will be in operational deployment. It estimated that the number of J-20s operated by the Chinese military increased from around 50 in 2020 to about 300 last year, while the number of J-16s rose from 90-100 to approximately 450 over a similar period.

On the 3rd, the U.S. nuclear-powered aircraft carrier USS Carl Vinson (CVN-70) arrived at the Busan operational base, and aircraft including F/A-18 fighters were lined up on its deck. Photo by the Joint Press Corps

The sixth-generation fighters that China is developing are two types, the J-36 and J-50. They are characterized by having three engines and a tailless triangular shape. They are designed to integrate advanced wideband stealth capabilities and to be optimized for high-speed air-to-air missions at high altitude. Missile performance has also been improved. China is operating air-to-air missiles such as the PL-15 and PL-17, which have a much longer range than weapons of the same class in the United States, Europe, or Russia. There is also a strong possibility that China will soon deploy the PL-16 into actual service, or that deployment has already begun.

South Korea at a crossroads: independent development or joint program

South Korea's planned sixth-generation fighter will be based on the KF-21. The KF-21 is a 4.5-generation fighter with partial stealth capabilities. Korea Aerospace Industries (KAI) plans to leverage the smooth progress of the KF-21 program to move directly from the development of a fifth-generation stealth fighter at Block-3 stage into the development of a sixth-generation manned-unmanned teaming (MUM-T) system.

The unmanned aircraft that will fly alongside the KF-21 is expected to be developed by Korean Air. Korean Air developed the Kaori-X1 unmanned aircraft in 2014. The Kaori-X1 is a scaled-down airframe representing 46% of a large unmanned combat aircraft, with a length of 10.4 meters, a wingspan of 14.8 meters, and a weight of 10 tons. By flying 50 kilometers over 1 hour and 30 minutes, the Kaori-X1 opened up the possibility of developing an unmanned combat aircraft. Korean Air further plans to use the Kaori-X1 to develop a "loyal wingman" type unmanned wingman aircraft and a "stealth unmanned reconnaissance aircraft." The unmanned wingman will be capable of manned-unmanned teaming, known as MUM-T. Before sending a manned fighter with a pilot on board into enemy territory, stealth unmanned wingmen will advance first. They can engage the enemy in combat or carry out reconnaissance missions at the front. Naturally, this helps protect the lives of fighter pilots. Since unmanned aircraft are deployed on missions simultaneously with manned aircraft, they can also respond to sudden and unexpected situations.