The first prototype G5N1 made its maiden flight on 14:35 8 April 1941. Overall performance proved disappointingly poor however, due to a combination of excessive weight, the unreliability of the Mamori engines and the complexity of the design.
On April 8, 1941, at 14:35, the first G5N1 prototype flew but its performance was unsatisfactory. This was attributed to excessive weight, engine unreliability, and the intricate nature of the aircraft's design.