The basic concept is to produce a "slim and high-power" engine, thereby creating more capacity for accommodating fuel and weaponry inside the fuselage of stealth fighter to reduce radar cross section.

[3] While its predecessor, the XF5, was a small engine, the XF9-1 prototype is close to the General Electric F110 in size, and is comparable to the Pratt & Whitney F119 in terms of thrust class.

The concept, slim and high-power, resulted in an approximately 30% higher thrust per unit cross-sectional area compared to the GE F110 the Mitsubishi F-2 is equipped with.

To achieve this thrust level, a higher combustion temperature (1,800°C class) and an optimized aerodynamic design were needed, which in turn required advanced material, manufacturing, cooling and fluid analysis technologies.

[7] The combustor is equipped with patented new-type burners, Wide-angle Swirler, to facilitate stable combustion and more uniform heat distribution at the outlet.