Nakajima J5N Tenrai
The Nakajima J5N Tenrai was an abandoned Japanese prototype fighter aircraft of the World War II era.
J5N was developed as twin-engine interceptor for countering attacks by Boeing B-29 Superfortress.
Design and development
During the spring of 1943, the JNAF issued an 18-Shi specification for a single-seat twin-engine interceptor capable of reaching a top speed of 666 km/h at 6,000 m. Nakajima submitted a proposal based on the earlier J1N1 Gekko three-seat night fighter, although this new aircraft – designated J5N1 – was slightly smaller. The layout of the J5N was similar to the J1N: a low set wing on which were mounted the two powerplants, 1,484 kW Nakajima Homare 21 18-cylinder air-cooled radial engines, with a long fuselage ending in a conventional tail arrangement. For maximum utilization of the power from the twin engines, large four-blade propellers were fitted which also featured large spinners. The main wheels retracted rearwards into the engine nacelles, and the tailwheel was fixed. The cockpit was set above the wing, and featured a starboard-opening canopy. The nose was streamlined to offer the pilot an excellent forward view during landing, takeoff and taxiing.Armament of the J5N consisted of two 30 mm and two 20 mm cannon, and provision was made for a centreline 250 kg bomb. The J5N was designed to combat the large, heavily armed and fast B-29 Superfortress, and so required such heavy armament in order to do severe damage in the brief windows of time allowed for firing passes. To concentrate the firepower, the four cannons were mounted in the nose of the J5N; if a single-engine fighter were unfortunate enough to find itself in front of a J5N, a single hit from a 30mm shell would have been more than adequate to destroy it.