Japan's 'Godzilla' fighter: A stealth jet designed to outsize the F-22

Countries & Cities · Published 16 October 2026 Swipe more like this →

In short: When the U.S. banned the export of its premier stealth fighter, Japan didn't just look for a replacement; they set out to build something bigger. The Mitsubishi F-X was envisioned as a sixth-generation powerhouse, prioritizing massive range and payload over traditional stealth constraints.

The F-X program was born from necessity following the 1997 Obey amendment, which restricted the export of the Lockheed Martin F-22 Raptor. Seeking a domestic solution to replace its aging fleet, the Japanese Ministry of Defense (MoD) initiated a study in 2009 to develop a jet a generation ahead of contemporary fifth-generation aircraft. This led to the 'i3 Fighter' concept, which prioritized 'Informed, Intelligent, and Instantaneous' capabilities, including fly-by-optics and advanced gallium nitride semiconductors for radar performance.

Technologically, the F-X was designed to be a 'Godzilla'—a nickname given by Aviation Week due to its larger size compared to the F-22. This scale was intended to provide long range and a large payload without requiring external stores, which would compromise stealth. To achieve this, engineers moved away from conventional hydraulics toward electric actuators. Because wiring is thinner and more flexible than hydraulic piping, this shift allowed for more freedom in designing internal weapon bays and air-ducts while reducing weight and complexity.

The aircraft also pioneered 'integrated/fastenerless' structures, using adhesive molding to bond composite materials. This technique, combined with carbon-fiber reinforced polymers (CFRP) and heat shield technology, was projected to reduce the airframe's theoretical structural mass by 11.6%. While Japan initially sought to develop the F-X as a domestic project, the path shifted toward international cooperation. In December 2022, the F-X program merged with the UK and Italy's projects to form the Global Combat Air Programme (GCAP), effectively ending the F-X as a standalone Japanese initiative.

Development was bolstered by the Mitsubishi X-2 Shinshin demonstrator, which flew in 2016. The F-X also utilized a 3-D digital mock-up system, allowing JASDF pilots to test design changes in a research flight/battle simulator. This synthetic testing environment allowed the MoD to rapidly gauge the effectiveness of avionics and stealth characteristics before physical production began.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• Japan's first supersonic strike fighter was born from a trainer aircraft
• The Mitsubishi F-2: How a Fighter Jet Became a Symbol of Diplomatic Friction
• How Japan transformed the American F-15 Eagle into its own unique air interceptor
• Japan’s indigenously developed T-4 trainer was built to outperform international rivals while staying subsonic.
• Beyond the postcard, Moʼorea is a living laboratory for understanding our changing planet.
• A remote volcanic archipelago in the Southern Ocean is literally growing before our eyes.
• Molokaʻi: The Hawaiian island that chose isolation over mass tourism and development
• How a French-based creole became the unifying voice of a diverse island nation
• The Mountain Time Zone is a shifting patchwork of local rules and solar geography
• Why this Japanese archipelago is considered one of the nation's three most beautiful views
• The village that preserved a dying language and a maritime legacy
• The Mascarene Islands are the remnants of a lost continent and ancient volcanic fire.

More in Islands · More in Countries & Cities · Latest · A–Z · All topics