POWER: 1 x Mitsubishi Ha-211 Ru 18-cylinder air-cooled radial piston engine developing 1,300 horsepower (2,200 horsepower maximum).
The Mansyu Ki-98 was a mid-war entry attack-minded aircraft development by the Japanese and originally designed to an Imperial Japanese Navy (IJN) 1942 requirement during World War 2 (1939-1945). The Ki-98 was entered by the Manchuria Airplane Manufacturing Company (known as "Mansyu" or "Mansu") against the Kawasaki Ki-102 ("Randy") series but neither project saw much fruit until 1944 when he Ki-102 was formally introduced. The war situation for Japan had turned for the worse and the Ki-102, in limited production, was used mainly for homeland defense. The Ki-98, meanwhile, was redrawn as a high-altitude fighter (complete with turbosuperchargers) but even this initiative fell to naught - the Japanese Navy was a shell of its former self and the Imperial Japanese Army Air Force (IJAAF) was now the last line of defense for the Japanese homeland.
The Manchuria Airplane Manufacturing Company was established in 1938 as a Japanese puppet state named "Manchukuo" making up Inner Mongolia. Manchukuo itself was established in 1932 following the Japanese takeover and existed until the end of the war in 1945. The company was arranged to take on production of many Japanese military aircraft, from the Kawasaki Ki-10 "Perry" biplane fighter of 1935 to more advanced types as the war progressed. The location also provided the Japanese Empire with a production hub far away from the Japanese homeland and its major industrial locations falling evermore under the crosshairs of American bombers. Mansyu completed nearly 2,200 aircraft during its wartime participation until the facility finally fell under Soviet control in 1945 and its equipment relocated to Soviet factories as war payment.
As finalized, the Ki-98 featured a crew of one and its dimensions included a length of 37.4 feet, a wingspan of 37 feet and a height of 14 feet. Empty weight was 7,715lb with a gross weight of 9,920lb. Power was from a single Mitsubishi Ha-211 "Ru" 18-cylinder air-cooled radial piston engine arranged in a "pusher" configuration, the engine installed at the rear fuselage, and outputting 2,200 horsepower during take-off (cruising power was to be closer to 1,750 horsepower). The engine, fitted just behind the cockpit, drove a four-bladed constant speed propeller unit by way of a seven foot extension shaft. Performance specifications (estimates) were a maximum speed of 455 miles per hour, a range out to 775 miles and a service ceiling of 32,800 feet.
Proposed armament for the design was a single 37mm Ho-204 cannon coupled with 2 x 20mm Ho-5 series cannons. It is conceivable that the aircraft (as a dedicated attack platform) would have also sported launch rails for rockets and hardpoints for conventional drop bombs.
The design ended as a twin-boom configuration with the fuselage being a tubular nacelle tapered at both ends. Armament was fitted to the nose, the cockpit just aft of the guns and the engine taking up the rear section of the fuselage nacelle. Wings were fitted aft of midships and were of a straight design with clipped tips. The tail booms emanated from the wing mainplane trailing edges and ended with rounded vertical tail fins, these fins joined by way of a shared horizontal tailplane. The undercarriage, wholly retractable and wheeled, was of a tricycle arrangement. A clean and modern design, the Ki-98 was a promising late-war addition to the Japanese arsenal.
The sole prototype, under construction by the time of the Japanese surrender, was destroyed by its owners lest it fell into enemy hands - the Soviets were making considerable progress into Manchuria.