Yokosuka K5Y

The Yokosuka K5Y was a two-seat unequal-span biplane trainer (Allied reporting name: "Willow") that served in the Imperial Japanese Navy during World War II. Due to its bright orange paint scheme (applied to all Japanese military trainers for visibility), it earned the nickname "aka-tombo", or "red dragonfly", after a type of insect common throughout Japan.

Design and development
The aircraft was based on the Yokosuka Navy Type 91 Intermediate Trainer, but stability problems led to a redesign by Kawanishi in 1933. It entered service in 1934 as Navy Type 93 Intermediate Trainer K5Y1 with fixed tail-skid landing gear, and remained in use throughout the war. Floatplane types K5Y2 and K5Y3 were also produced. After the initial 60 examples by Kawanishi, production was continued by Watanabe (556 aircraft built), Mitsubishi (60), Hitachi (1,393), First Naval Air Technical Arsenal (75), Nakajima (24), Nippon (2,733), and Fuji (896), for a total of 5,770. These aircraft were the mainstay of Imperial Japanese Navy Air Service's flight training, and as intermediate trainers, they were capable of performing demanding aerobatic maneuvers. Two further land-based versions, the K5Y4 with a 358 kW (480 hp) Amakaze 21A engine and the K5Y5 with a 384 kW (515 hp) Amakaze 15, were projected but never built.

Variants

 * K5Y1:
 * Two-seat intermediate trainer for the Imperial Japanese Navy.
 * K5Y2:
 * Floatplane version, with Amakaze 11 engine.
 * K5Y3:
 * Floatplane, with 384 kW (515 hp) Amakaze 21.
 * K5Y4:
 * Projected land-based version with 358 kW (480 hp) Amakaze 21A. Never built.
 * K5Y5:
 * Projected land-based version with 384 kW (515 hp) Amakaze 15. Never built.

Operators

 * Imperial Japanese Navy
 * Imperial Japanese Navy

Postwar

 * Indonesian People's Security Force operated derelict aircraft against Dutch colonial rule. On 29 July 1947, Indonesia beside using Guntei and Planned,Hayabusa.Indonesia also use 2 units Yokosuka K5Y(Called "Cureng/Churen" by Indonesian fighters) from Maguwo Air Force Base, Yogyakarta for bombing Dutch strategic positions in Ambarawa, Salatiga and Semarang. It is currently on display at Jakarta.