The Kawanishi E15K Shiun (紫雲, "Violet Cloud") was a single-engined, Japanese reconnaissance floatplane of World War II.

[1] In 1939, the Imperial Japanese Navy instructed the Kawanishi Aircraft Company to develop a two-seat, high-speed reconnaissance floatplane, which was required to have sufficient performance to escape interception by land-based fighters as well as an 800-nautical mile range.

[2] It was planned to equip a new class of cruisers, intended to act as a flagship for groups of submarines, operating six of the new floatplanes to find targets.

Compounding Japanese crews' undoubted frustration, when under attack, the Shiun's main float jettison mechanism, which had been wind-tunnel tested but never tried on an actual airplane prior to manufacture, failed to work in combat.

Coupled with high maintenance and other mechanical issues, further production was cancelled in February 1944, with only fifteen Shiuns completed - including the six prototypes.