Design
The Mitsubishi F1M was designed to be a catapult launched observation floatplane.1 It was to meet a late 1934 Imperial Japanese Navy specification for a replacement for the Nakajima E8N1.1,2 Aichi and Kawanishi also tried to meet the requirements.2 Kawanishi withdrew and Aichi's was inadequate.2
The Mitsubishi design team was lead by Joji Hattori.2
A couple problems the F1M had was it would often porpoise in water and directional stability in flight.1
Floats
There was a main, central, float, and two stabilizers attached to the lower wing.2
Upgrade
The F1M2 was a major redesign that appeared in 1939.1
