According to experts, South Korea must prioritize software-based performance upgrades over hardware improvements to enhance the competitiveness of its fighter jets, including the KF-21 Boramae.
On Tuesday, the Korea Institute for Defense Analyses (KIDA) reported that Chief Research Fellows Lee Joo Hyung and Park Soo Hyun, along with Research Fellow Park Sang Hyun and Senior Researcher Lee Dong Yeon, made this assertion in a recent Defense Forum article titled Implications for Next-Generation Fighter Development from F-35 Performance Upgrades.
The F-35, a fifth-generation fighter jet, has been developed for over twenty years since the prototype was introduced. Although it is a best-selling aircraft, with over 1,000 units sold across 18 countries, including the United States, it is still considered a work in progress. The F-35 was designed with a phased upgrade system, which gradually implements improvements.
Performance improvements in the F-35 are achieved through modular software updates designed to counter emerging threats. U.S. military officials describe the F-35 as a flying computer in stealth aircraft form, constantly downloading new programs to enhance its capabilities.
The Republic of Korea Air Force acquired 40 F-35As between 2019 and 2022 and recently inked a deal for an additional 20 jets in December 2023. These aircraft are slated for ongoing upgrades, including the advanced Block 4 configuration.
This approach closely mirrors the business model of Tesla, a leading global electric vehicle company. While traditional automakers have focused on delivering performance through hardware that supports the core value of transporting people and goods, Tesla has taken a different path, offering features such as ‘Autopilot’ through software updates. In doing so, the company has shifted the paradigm of the automotive industry from a hardware-centric to a software-driven model.
The researchers explained that unlike fourth-generation fighter jets, which undergo major performance upgrades after long deployment periods, the F-35 undergoes small-scale enhancements every six months. This ensures greater adaptability to rapidly evolving threats.
They further explain that the F-35’s extensive sensor suite enables data fusion capabilities, equipping it to operate effectively in multi-domain environments encompassing cyber, electronic, and space warfare. This versatility is a key factor driving widespread F-35 adoption.
South Korea’s indigenous KF-21, currently being developed as a 4.5-generation fighter, is expected to produce variants, including an electronic warfare (EA) version, a stealthy configuration with internal weapons bays (EX), and an export model (SA).
However, the researchers caution that this hardware-centric approach may be outdated. They argue that a policy shift prioritizing software development for domestic fighters is crucial to align with future combat aircraft trends.
The emphasis on software-driven fighter development also ties into the concept of sixth-generation aircraft, which will likely feature AI-enabled manned-unmanned teaming capabilities. The researchers suggest that if F-35s can achieve similar capabilities through software upgrades, it may reduce the urgency for entirely new sixth-gen platforms.
The team concludes that if South Korea aims to evolve the KF-21 into a fifth or sixth-generation fighter, adopting an F-35-style upgrade path would be most effective. By maintaining the basic airframe while continuously enhancing capabilities through software, South Korea can maximize cost-effectiveness and streamline long-term logistics support.