Kawanishi N1K1 Kyofu (Rex)
Kyofu (Mighty Wind). Allied code name "Rex". Designed as a more advanced, specifically designed seaplane fighter. The first N1K1 prototype took off on its first flight on May 6, 1942. Service trials aircraft were delivered to the Japanese Navy starting in August of 1942. Early production aircraft were powered by 1460 hp MK4C Kasei 13 engines, but later production aircraft were powered by 1530 hp MK4E Kasei 15 engines which differed only in minor details. The Kyofu entered service with the Japanese Navy in July of 1943. Production was slow in gearing up and by December of 1943, it had reached only 15 aircraft per month.
By the time that the Kyofu entered service, Japan had been thrown back onto the defensive, and the Kyofu was never to serve in the offensive fighter role for which it had been designed. Instead, the the N1K1 was assigned as an interceptor based at Balikpapan in Borneo, a role for which it had never been intended. Even though the Kyofu was a rugged and efficient floatplane, it was no match for the single-seat Allied fighters. Production was terminated in March of 1944 after the delivery of only 89 production aircraft.
Later in the war, one Kyofu unit was assigned as an interceptor with the Otsu Kōkūtai operating from the inland Lake Biwa on the Japanese home island of Honshu.