Radar cannot fully replace Ibuki's seaplanes

Could the Ibuki-class cruisers rely entirely on radar and eliminate their seaplane facilities?

Not for the reconnaissance role Japan expected, although moving aviation scouting to small carriers would free cruiser space for better structure and protection.

Radar would not replace the aviation reconnaissance role assigned to Japanese cruisers. Ibuki was intended to carry three aircraft and two catapults alongside ten 8-inch guns in five twin turrets. Moving reconnaissance to small carriers would remove the need to accommodate those aviation facilities within the cruiser. The freed space could allow a better structural arrangement and protection scheme, and construction could be quicker. Ibuki's later conversion toward a carrier with twenty-seven aircraft shows how extensively that unfinished hull's intended role changed.