The Yokosuka E6Y / Yokosuka Navy Type 91-1 Reconnaissance Seaplane, was a Japanese submarine-based reconnaissance seaplane developed at the Yokosuka Naval Air Technical Arsenal for the Imperial Japanese Navy during the 1920s.
The prototype first flew as the Yokosho 2-Go / Yokosuka Arsenal No. 2 Reconnaissance Seaplane in 1929.
The aircraft was a single-seat biplane that could be quickly assembled and disassembled so that it could be stored on board a submarine.
Two prototypes were built that differed in power plant and design details.
Eight production machines followed with the designation E6Y built by Kawanishi in the 1930s and served with the Japanese submarine aircraft carriers I-5, I-6, I-7 and I-8.
They saw limited action during the January 28 incident and the Second Sino-Japanese War, the last example being retired in 1943.
Variants
Yokosho 2-Go
First prototype equipped with a 130 horsepower (97 kW) Mitsubishi-licensed Armstrong Siddeley Mongoose.
Yokosho 2-Go Kai
Second prototype equipped by a 160 horsepower (120 kW) Gasuden Jimpu
E6Y1
Production version of the 2-Go Kai manufactured by Kawanishi.