The Ki-9 was originally planned to be manufactured in two versions using the same basic airframe, but with different engines for service as either a primary or intermediate trainer. However, when the lower-powered form proved to be unsuitable due a center of gravity issue, design of a new airframe was ordered for the basic trainer version, and was given the new designation of Ki-17.
Compared to the Ki-9, the Ki-17 had equal-span wings, a slimmer fuselage and a revised tailplane. It was powered by a 112-1NaN-1 Hitachi Ha-13a radial engine. The first prototype flew in July 1935.
The only major change made to subsequent production aircraft was the deletion of the upper-wing ailerons to eliminate oversensitive control inputs.
The Ki-17 was introduced to service as the Army Type 95-3 Basic Grade Trainer Model A under the former aircraft naming nomenclature system. Tachikawa manufactured 560 Ki-17s between 1936 and 1943 and the type saw service with the Army Air Academy and flight training schools.
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