The Nakajima Ki-4 Kyūyon-shiki teisatsuki (九四式偵察機) was the last biplane reconnaissance aircraft of the Japanese Imperial Army.
The Ki-4 was initially produced by Nakajima in response to a 1931 specification for a high-performance reconnaissance aircraft that could also be used in the light ground support role.
[1] The Nakajima Ki-4 was a biplane design with staggered wings and fixed, divided landing gear.
A total of 516 units were produced, 333 by Nakajima between March 1934 and February 1939, fifty-seven under license by Tachikawa Aircraft Company Ltd, and another 126 by Manshū in Manchukuo (Manchuria).
They also functioned as light ground-attack aircraft in the support of advancing Japanese ground troops.