This single-engine, land-based tactical fighter was flown by the Imperial Japanese Army Air Force in World War II and featured the army designation of "Army Type 4 Fighter". Code-named "Frank" by the Allies, the Ki-84 was considered to be the best Japanese fighter to see large-scale operations during the war. With excellent performance and maneuverability, it could outmatch any Allied fighter and intercept the high-flying B-29 Superfortress. Exactly 3,514 were built, with armament that could include two 30mm and two 20mm cannons. After the war, a captured Ki-84 was tested by the U.S. using high-octane fuel. It achieved a speed of 687 km/h (426 mph).