TYPE: Interceptor, fighter

ACCOMMODATION: Pilot only

POWER PLANT: Two Ishikawajima Ne-20 turbojet engines, rated at 475 kp each

PERFORMANCE: 433 mph at 32,800 ft (estimated)

COMMENT: Design work on the Nakajima J8N “Kitsuka” (“Kikka”) – the only Japanese turbojet powered aircraft capable of taking-off on its own power, albeit only twice during World War II – began in September 1944. The enthusiastic reports on the progress of the Messerschmitt Me 262 twin-jet fighter received from the Japanese Air Attaché in Germany had prompted the Naval Staff to instruct Nakajima to design a single-seat twin-jet attack fighter based on the German Me 262.
The aircraft externally resembled the Me 262 but was smaller. Two turbojets were mounted in separate nacelles under the wing to allow the installation of engines of various types. Provisions were made for folding wings, to enable the aircraft to be hidden in caves and tunnels and also for ease of production by semi-skilled labor. Initial plans to power the aircraft by two N-12 turbojet engines each delivering 340 kp thrust were refused due to insufficient thrust. Fortunately, photographs of the German BMW 003 axial-flow turbojet had been obtained and from these the Japanese were able to design a similar turbojet, designate Ne-20, offering a thrust of 475 kp.
Completed in August 1945, the first “Kikka” made its maiden flight. Four days later the pilot aborted a take-off during the second flight, the accident being caused by mounting the two rocket-assisted-take-off (RATO) rockets at an incorrect angle. A second prototype (shown here) was almost ready for flight trials and eighteen additional prototypes and pre-production aircraft were ready in various stages of assembly when with the end of WW II the development of the aircraft was terminated (Ref.:  1).

TYPE: Interceptor fighter

ACCOMMODATION: Pilot only

POWER PLANT: One Mitsubishi MK4R-A Kasei 23a radial engine, rated at 1,800 hp

PERFORMANCE: 365 mph at 17,390 ft

COMMENT: The Mitsubishi J2M “Raiden” was a single-engine land-based fighter aircraft used by the Imperial Japanese Navy Air Force in World War II. The Allied reporting name was “Jack”. The J2M was designed to be a strictly local-defense interceptor, intended to counter the threat of high-altitude bomber raids, and thus relied on speed, climb performance, and armament at the expense of maneuverability. The J2M was a sleek, but stubby craft with its over-sized Mitsubishi Kasei engine buried behind a long cowling, cooled by an intake fan and connected to the propeller with an extension shaft.
Teething development problems stemming from the Kasei engine cooling system, and the main undercarriage members led to a slowdown in production.  The first few produced J2M2s were delivered to the development units in December 1942 but severe problems were encountered with the engines. Trials and improvements took almost a year and the first batch of the serial built J2M2 was delivered in December 1943. Parallel with the J2M2, production of the J2M3 “Raiden” started. The first J2M3s appeared in October 1943 but deliveries to combat units started at the beginning of February 1944.The “Raiden” made its combat debut in June 1944 during the Battle of Philippine Sea. Several J2Ms operated from Guam and Saipan and a small number of aircraft were deployed to the Philippines.
Primarily designed to defend against the Boeing B-29 “Superfortress”, the lack of a turbocharger handicapped the aircraft at high altitude. However, its four-cannon armament supplied effective firepower and the use of dive and zoom tactics allowed it to score occasionally. Insufficient numbers and the American switch to night bombing in March 1945 limited its effectiveness (Ref.: 24).

TYPE: Float seaplane fighter

ACCOMMODATION: Pilot only

POWER PLANT: One Mitsubishi MK4D “Kasei 14” radial engine, rated at 1,460 hp, driving contra-rotating two-blade propellers

PERFORMANCE: 300 mph at 17,650 ft

COMMENT: Appearing too late to serve in its intended role, the Kawanishi N1K1 “Kyofu (“Mighty Wind”) floatplane fighter participated only briefly in combat operations but it sound design led to its adaptation into one of the most successful land-based fighter aircraft of WW II, the Kawanishi N1K1-J “Shiden”.
Development of a series of floatplane fighters intended to provide air support to Japanese amphibious landing forces in areas where no airfield existed was initiated in 1940, while Nakajima Hikoki K.K. undertook the development of an interim aircraft – the A6M2-N – Kawanishi Kokuki K.K  were instructed to initiate the design of an aircraft specially conceived for that purpose. Issued by the Japanese Navy in September 1940 planning began immediately in the Kawanishi engineering office. Basing their efforts on the advanced technology developed for the Kawasnishi E15K1 “Shiun”, a team of engineers designed a compact floatplane with mid-mounted wings of laminar-flow section. Like the “Shiun”, the projected floatplane fighter, then known by the designation of K-20, was to be powered by a 1,460 hp Mitsubishi MK4D “Kasei 14” driving two contra-rotating two-blade propellers to offset the anticipated propeller torque on take-off. The central float was to be attached to the fuselage by a V-strut forward and an I-strut at the rear, but the proposed use of retractable stabilizing floats with metal planning bottom and inflatable rubberized-fabric tops could be traced to the “Shiun’s” design philosophy. Difficulties encountered with this type of float during the early part of E15K1 flight trial programme led to their replacement by fixed cantilever floats prior to the aircraft’s first flight.
Following the completion the first N1K1 made its successful maiden flight on 6 May, 1942. However, teething troubles with the contra-rotating propeller gear box – similar to those experienced in the E15K1 programme – led to the decision to replace the “Kasei 14” engine by a MK4C “Kasei 13” driving conventional three-blade propeller via an extension shaft. Once in the air the N1K1 was an extremely pleasant aircrafts to handle and the use of combat flaps gave it remarkable maneuverability. Finally, based on these good results the Japanese Navy ordered the aircraft into quantity production as the Navy Fighter Seaplane “Kyofu Model 11”, (Kawanishi N1K1 “Kyofu”) and deliveries of production aircraft began in spring 1943 (Ref.: 1).

TYPE: Float seaplane fighter

ACCOMMODATION: Pilot only

POWER PLANT: One Mitsubishi MK4E “Kasi 14” radial engine, rated  at 1,400 hp

PERFORMANCE: 304 mph at 18,700 ft

COMMENT: Satisfied with the results of the flight trial progamme of the prototypes of the Kawanashi N1K1 the Imperial Japanese Navy ordered the aircraft into quantity production as the Navy Fighter Seaplane “Kyofu Model 11”, and deliveries of production aircraft began in spring of 1943 following the completion of eight prototypes and service trials aircraft. But production was slow in gaining tempo and by December 1943, when the delivery rate had reached fifteen aircraft per month, the decision was taken to cease manufacture of the “Kyofu” and the last N1K1 was delivered in March 1944. This decision did not indicate any misgiving on the aircraft’s capability but merely reflected the fact that the war had taken an unfavourable turn for Japan which no longer needed a fighter to support offensive operations.
The war situation was also reflected in the operational use of the aircraft in a defensive role and N1K1s (Allied code name “Rex”) were assigned as interceptors in the Borneo Area of Action. Late in the war the “Kyofu” was assigned to similar duties with the Otsu Kokutai operating from Lake Biwa as an air defence unit (Ref.: 1).