The K6K was a 2-seat twin-float biplane with a welded steel-tube fuselage, covered in fabric, light alloy and steel wing covered in fabric and monocoque floats built from light alloy. It was conceived in response to an Imperial Japanese Navy requirement for an intermediate-level training seaplane. The first flight of the K6K occurred on 30 April 1938, but flight tests revealed poor alighting characteristics, so the K6K was not ordered into production.[1]
1 X as second letter is for experimental aircraft or imported technology demonstrators not intended for service,
2 Hyphenated trailing letter (-J, -K, -L, -N or -S) denotes design modified for secondary role, 3 Possibly incorrect designation, but used in many sources