The IJA Type 99 Ki-51 «Sonia» was a very successful Japanese ground attack aircraft that remained in service throughout the Second World War. It was developed from the IJA Type 97 Ki-30, a light bomber that made its maiden flight in February 1937 and entered service in 1938. Work on the Ki-51 began in December 1937 at the suggestion of Captain Yuzo Fujita. The new aircraft had to be manoeuvrable, and because it was expected to operate at low levels, to be unusually heavily armoured for a Japanese aircraft of this period. The Ki-51 resembled a smaller version of the Ki-30. It used a similar fuselage and the same wing form, although the wings were mobbed from their mid-position on the Ki-30 to the base of the fuselage to reduce the length of the fixed undercarriage. The cockpit was shortened, bringing the two crew members closer together. The bombs were carried externally.
The first two prototypes were completed in June and August 1939. Eleven service test aircraft followed by the end of the year – at this stage 6mm steel armour was added under the engine and cockpit. It had originally been planned to produce two versions of the Ki-51 – the Army Type 99 Assault Plane and the Ki-51a Army Type 99 Tactical Reconnaissance Plane, carrying cameras in the rear cockpit. Instead of this the Army decided to give every Ki-51 the ability to carry cameras, and the aircraft could easily be swapped between roles in the field. A total of 1,459 production aircraft were built by Mitsubishi and 913 by the Tachikawa Dai-Ichi Rikugen Kokusho (the Army’s own arsenal). During the production run the 7.7mm wing guns were replaced by two 12.7mm machine guns, but otherwise the design remained unchanged. Production ended in July 1945. The Ki-51 was used in a close support role in China and in every theatre where the Japanese Army fought during the Second World War. Although the Ki-51 lacked speed it was manoeuvrable, and unusually for a Japanese aircraft of the Second War, well protected. It was also easy to maintain and could operate from small airfields close to the front line. As a result it remained in use until the end of the war, and in production until July 1945.

Today we are pleased to tell you that we have completed the design of our new model of this very interesting aircraft and are ready to show you the 3D rendering of the pre-production CAD model. We know that we spent a little more time than originally planned for this project and this is primarily due to the fact that there is very little reliable information on Ki-51. About the release dates and versions in which our new model will be released, we will inform you as we move forward on it. Thank you for your patience and understanding. Stay with us.

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