"Tora! Tora! Tora!"
- Predetermined Japanese signal indicating they had achieved complete surprise leading up to the aerial assault at Pearl Harbor, December 7th, 1941

The Nakajima B5N (Allied reporting name: Kate) was the Imperial Japanese Navy's standard torpedo bomber for the first years of World War II. While the B5N was substantially faster and more capable than its Allied counterparts, the TBD Devastator and Fairey Swordfish, it was close to obsolescence by the time of the Pearl Harbor Attack. Nevertheless, the B5N operated throughout the whole war. Although primarily used as a carrier-based aircraft, it was also used as a land-based bomber on occasions. The B5N had a crew of 3: pilot, navigator/bombardier/observer, and radio operator/gunner.

The B5N was designed by a team led by Katsuji Nakamura in response to a 1935 specification by the Navy for a torpedo bomber to replace the Yokosuka B4Y. Internally designated Type K by Nakajima, it successfully competed with the Mitsubishi B5M for a production contract. The first prototype flew in January 1937 and was ordered into production soon afterwards with the full designation Type 97 Carrier Attack Bomber.

The B5N soon saw combat, first in the Sino-Japanese War, where combat experience revealed several weaknesses in the original B5N1 production model. These were mainly concerned with the lack of protection that the design offered its crew and fuel tanks. Keen to maintain the high performance of the type, the Navy was reluctant to add weight in the form of armour, and instead looked to obtaining a faster version of the aircraft in the hopes of out-running enemy fighters. The B5N2 was given a much more powerful engine, and various modifications were made to streamline it. Although its performance was only marginally better, and its weaknesses remained unremedied, this version replaced the B5N1 in production and service from 1939. It was this version that would be used by the Navy in the attack on Pearl Harbor. Apart from this raid, the greatest successes of the B5N2 were the key roles they played in sinking the US Navy aircraft carriers Yorktown, Lexington and Hornet.

The B5N served as the basis for a follow-on design, the Nakajima B6N, which eventually replaced it in front-line service. The B5N continued to fly in secondary roles, such as training, target towing, and anti-submarine warfare. Some of the aircraft used for this latter purpose were equipped with early radars and magnetic anomaly detectors. B5Ns were also used as bombers during the unsuccessful defense of the Philippines in October 1944.

Pictured here is a 1:72 scale replica of an Imperial Japanese Navy Nakajima B5N1 "Kate" torpedo bomber that was attached to the Usa Naval Air Group, from 1943-44. Sold Out!

Dimensions:
Wingspan: 8-1/2-inches
Length: 5-3/4-inches

Release Date: October 2015

Historical Account: "Operation Ketsugo" - The Japanese had developed extensive plans for the defense of their home islands by the end of WWII. Initially, they were concerned about an invasion during the summer of 1945. However, the Battle of Okinawa went on for so long that they concluded the Allies would not be able to launch another operation before the typhoon season, during which the weather would be too risky for amphibious operations. Japanese intelligence predicted fairly closely where the invasion would take place: southern Kyūshū at Miyazaki, Ariake Bay, and/or the Satsuma Peninsula.

While Japan no longer had a realistic prospect of winning the war, Japan's leaders believed they could make the cost of conquering Japan too high for the Allies to accept, which would lead to some sort of armistice rather than total defeat. The Japanese plan for defeating the invasion was called Operation Ketsugo ("Operation Codename Decisive"). The Japanese were secretly constructing an underground headquarters in Matsushiro, Nagano Prefecture, which could be used in the event of Allied invasion to shelter the Emperor and the Imperial General Staff. It is worth noting that in planning for Operation Ketsugo, IGHQ vastly overestimated the strength of the Allied forces they would be facing: while the actual Allied invasion plan called for as many as 54 divisions (14 for Olympic and 38-40 for Coronet), the Japanese expected up to 90.