Nakajima Ki-84 Hayate

The Nakajima Ki-84 Hayate, known as "Frank" in the Allied jargon, was one of the best IJAAF (Imperial Japanese Army Air Force) fighters during the final year of the Pacific war. Featuring an enclosed cockpit and retractable landing gear, this all-metal cantilever low-wing monoplane of an elegant body was the successor of the previous Nakajima fighters – the Ki-43 Hayabusa and Ki-44 Shoki. 

The Ki-84 proved its value fighting in China and the Philippines, although the highest number of these machines were lost there, too. When in the hands of an experienced pilot, it was a good match for the best of Allied fighter aircraft. After the war a small number of Ki-84s served with the Chinese air forces, taking part in the civil war of 1945-1949.

Nakajima Hikoki Kabushiki Kaisha

The history of the Nakajima company, one of the oldest and best known Japanese aircraft manufacturers, dates back to December 6, 1917, when a former Chui of the Imperial Navy, Chikuhei Nakajima, established a company named Hikoki Kenkyusho (Aircraft Research Institute) near the Daikoin Temple in Ota. When still a navy officer, Nakajima had been sent to the United States in 1912 to study aircraft construction and complete pilot training at the Glenn Curtiss factory and school of aviation. In April 1918 Chikuhei Nakajima renamed his company Nakajima Hikoki Seisakusho (Nakajima Aeroplane Manufacturing Works). A little later, when the industrialist Seibei Kawanishi (who would later establish his own aircraft company, Kawanishi Kokuki KK) joined the venture, the name was changed to Goushikaisha Nihon Hikoki Seisakusho (Japan Aeroplane Works Co. Ltd.). The beginnings were modest, but in April 1919 the new company received first big orders for a self-designed two-seat training biplane, the Nakajima-Shiki Go-Gata (Type Nakajima Model 5). By May 1921 the company had built 118 of these aircraft for both the Imperial Army and non-military customers.
Owing to differences of opinion, Seibei Kawanishi had in the meantime left the company, with which regard in December 1919 Chikuhei Nakajima restored the former company name, Nakajima Hikoki Seisakusho. In 1920 the company received the first order from the Imperial Navy. In 1924 Nakajima decided to undertake engine manufacturing, for which purpose he established a factory at Ogikubo in the suburbs of Tokyo. The further development of the company was made possible owing to a big (for those times) contract to build Ko-Shiki Yon-Gata Sentoki aircraft (Typ Ko Model 4 Fighter), with more than 600 of these built over the years 1923-1932. They were actually licensed French Nieuport 29C1s, but they provided Nakajima with the resources and experience to design in the late 1920s its first own fighter, the 91-Shiki Sentoki (Type 91 Fighter). This construction was born with the help of engineer Yasushi Koyama, the father of almost all the future Nakajima fighters built for the Army Air Force.
Nakajima once more renamed the company in December 1931, this time Nakajima Hikoki Kabushiki Kaisha (Nakajima Aeroplane Co. Ltd.). At the same time he retired and became involved in politics, while still retaining the honorary title of the company's president. Control of the business was taken over by his younger brother, Kiyoichi Nakajima. In the following years the company designers began to experiment with new ideas and technologies developing in fighter construction. This gave birth to the metal monoplane Ki-8, Ki-11 and Ki-12 fighters (the latter featuring retractable landing gear and armed with a 20-mm cannon).

Hayate Ki84-fot-121


The constantly developed aircraft and engine factories of Nakajima, including the subsidiary Nakajima Koku Kinzoku KK (Nakajima Aero-Metal Co. Ltd.), grew into a practically self-sufficing industrial unit which manufactured almost all of the more important parts and sub-assemblies used in aircraft production (with the exception of propellers). This made Nakajima the Second World War's greatest Japanese aircraft manufacturer and placed it as the second best right behind Mitsubishi in aircraft engine production. Throughout 1941-1945 the company built 28 percent of all the aircraft produced in Japan (or no less than 37.1 percent if we only consider military aircraft) and 31.3 percent of engines.

The origin and development

The design

As the war broke out in the Pacific, the fighter component of the IJAAF was still based on the Ki-27, a light low-wing monoplane with fixed landing gear designed in 1937 (see Monograph no. 11). It was being replaced by the more modern Ki-43 Hayabusa with retractable landing gear, while another fighter, the Ki-44 Shoki – heavier and less agile but faster, with a more powerful engine and stronger armament – was undergoing operational trials. All the three types were genuine Nakajima designs.