The Mogami Class cruisers were designed to maximize firepower in the guns and torpedo fit. Originally designed for 15 six-inch guns with a heavy battery of 24-inch "Long Lance" torpedoes, the class was subsequently refitted with 10 eight-inch guns, while keeping the strong torpedo fit. Given the fact that the class was designed to maximize fire-power, the subsequent history of the Mogami is ironic.
Mogamiwas present at the Battle of Midway when Japan lost four of her six front line carriers and with them and the lost crack aircrews, the mastery of the air that had been enjoyed by Japanese naval forces up to that time. Airpower was crucial in the halting of Japanese offensive plans and proved to be the turning point of the Pacific War. From then on, Japan was on the defensive as the USN had seized the initiative. Mogami was mauled by USN carrier aircraft during the battle and collided with sistership, Mikuma. Although the Mikuma was lost, the badly damaged Mogami was sent back to Japan for extensive repairs. With the loss of four front line carriers, Japan scrambled to find substitutes from a variety of forces.
The battleships Ise and Hyuga are the two most well known conversions of heavy gun warships into a gun power/aviation hybrids. Lesser known is the cruiser Mogami. In April 1943 Mogami rejoined the fleet as cruiser/seaplane carrier. The cruiser retained the three turrets on the forward part of the ship but the entire aft portion had been reworked. The two aft turrets had been landed, the aft freeboard had been raised and a flight deck for seaplanes covered the aft half of the ship. In this guise she carried Aichi E13A1 "Jake" and Mitsubishi F1M2 "Pete" reconnaissance seaplanes. The gun power of the original design had been sacrificed to add a sliver of additional naval aviation.
The loss of the Mogami is the final irony. In October 1944 Mogami was dispatched, with the battleships Fuso and Yamashiro, as the heavy units of the southern pincer of the Japanese forces at the Battle of Leyte Gulf. For a cruiser in which gun power had been sacrificed for naval aviation, Mogami found herself engaged in a night gunnery duel with the PT boats, destroyers, cruisers and battleships of the USN at the Battle of Surigao Strait. As Fuso and Yamashiro succumbed to naval gunfire, Mogami managed to turn around and head south out of the trap. With fires raging along the amidships, Mogami collided with the cruiser Nachi of the follow-on force. However, the damage to Mogami was too great and she too followed the two battleships to the bottom of the strait.
Navy Plan of France has produced an exceptional set of plans for Mogami, in her cruiser/carrier version in 1:100 scale. This set of plans comes with two large sheets of plans and a bound spiral notebook, which covers various and fittings details.
The first sheet of plans covers the overhead plan and starboard profile of the cruiser. They are meticulously drawn by Jean-Manuel Soumarť of Navy Plan to show all of the detail if this "hard luck" cruiser. Included among the mass of detail are intricate shipís boats plans and plans and profiles of the aircraft. Another nice touch in the plans is to show the inboard and outboard positions of the outboard shipís boats. The radii of the main guns and various davits are shown. Rigging is also shown on both the plan and profile views.
The second sheet shows the multitude of shipís lines in 1:100 scale, which will allow the modeler to capture the unique lines of this Japanese cruiser. The bow on view has 15 sections and the stern on view has 13 sections. Both the starboard profile and overhead plan included on this sheet show the 28 numbered sections placement along the length of the hull. By forming templates for each section and then placing the sections at the appropriate points along a template of the keel, the modeler can produce an accurate and extremely large hull for the cruiser.
Accompanying the two sheets is a spiral bound book that includes eighteen pages of details of various fittings for the ship. These detailed drawings include: 1. Port profile of C turret and barbette in 1:75 scale; 2. Plan of main gun turret in 1:75 scale; 3. Front and rear face of C turret and barbette in 1:75 scale; 4. Isometric view of A or B turret; 5. Details of turret mounted range finders; 6. Vertical ladder and turret edge detail; 7. Front and rear face views of 127mm twin DP mount in 1:50 scale; 8. Plan and starboard views of 127mm twin DP mount in 1:50 scale; 9. Port and isometric views of 127mm twin DP mount in 1:50 scale; 10. Plan and starboard views of triple 25mm AA mount in 1:20 scale; 11. Port and isometric views of triple 25mm AA mount ; 12. Front view of triple 25mm AA mount in 1:20 scale; 13. Port & starboard views of 610mm "Long Lance" torpedo mounts, along with torpedo outside of the tube in 1:50 scale; 14. Plan of 610mm "Long Lance" torpedo mount in 1:50 scale; 15. Port view of mainmast and crane in 1:100 scale with two detail insets; 16. Aft view of mainmast and four mast platform insets in 1:100 scale; 17. Overhead view of main mast and crane in 1:100 scale with three inset drawings showing supports detail; and 18. Front views of the Aichi E13A1 "Jake" and Mitsubishi F1M2 "Pete" seaplanes in 1:100 scale.