Japanese Battleship Pagodas

From Wikipedia.

Look at the pagoda mast of the Kongo at right.

The pagoda mast was a type of superstructure that was common on Japanese capital warships that were reconstructed in the 1930s in a bid to improve their fighting performance.  This came about because of restrictions put on Japan because of the Washington Naval Treaty which severely limited the construction of new battleships.

Pagoda masts were built on existing tripod masts by adding searchlight and other platforms, lookouts and shelters upon each other and led to something looking like a pagoda temple.  These new superstructures were built on the Kongo-class battlecruisers as they were turned into battleships, the Fuso, Ise and Nagato-classes of battleships.

These pagoda masts reached quite high.  For example, the top of the one on the battleship Fuso was 130 feet above the waterline.

The British Royal Navy was considered to be a likely enemy in a war and it was determined that the Japanese would have a better chance fighting them at night time.  The Japanese had developed powerful searchlights and placed them on the pagoda masts with the purpose of illuminating enemy ships.

However, during the early 1940s the development of radar enabled the targeting of enemy ships at night, which negated the value of the searchlights.

--GreGen