The versatile Mitsubishi F1M 'Pete' was developed as a catapult-launched observation floatplane but ended up serving in a bewildering amount of different roles along the Pacific. The F1M was an all-metal biplane with a large central main float and two outriggers (made with low drag mounts), like most Japanese aircraft it was also extremely maneuverable to the point that it was occassionally used as an interceptor, point defense fighter, and dive bomber. Despite these capabilities, it was in a number of naval duties that it stood out: F1Ms performed coastal and ocean patrol, convoy escort, search and rescue, transport, anti-submarine warfare, and general bombing missions from both ships and sheltered water bases. 'Petes' equipped everything from converted seaplane tenders to the battleships and cruisers of the IJN and were present in nearly every major battle or campaign including Midway, the Solomons, the Marianas, and Leyte Gulf among others.

The F1M began life as a replacement for the E8N1 and competed with a rival Aichi design for a late 1934 IJN requirement. The first prototype Ka-17 took to the air in June 1936 and entered service with the military designation F1M1. It was later improved into the F1M2 which became the only major production version built by Mitsubishi and the Dai Nijuichi Naval Air Arsenal with the last delivery made as late as 1944. Besides these, an advanced trainer conversion was known as the F1M2-K.