The Nakajima G8N Renzan ( "Mountain Range") was a four-engine long-range bomber designed for use by the Imperial Japanese Navy. The Navy designation was "Type 18 land-based attack aircraft
n February 1943 the Imperial Navy staff asked Nakajima Aircraft Company
to design a four-engined bomber, capable of meeting an earlier specification set for a long-range land-based attack plane. The final specification, issued on 14 September 1943, called for a plane with a maximum speed of 320 knots (590 km/h; 370 mph) able to carry a 4,000 kg (8,800 lb) bomb-load 2,000 nmi (3,700 km; 2,300 mi) or a reduced bomb-load 4,000 nmi (7,400 km; 4,600 mi).
Nakajima's design featured a mid-mounted wing of small area and high aspect ratio, a tricycle landing gear and a large single-fin rudder. Power came from four 2,000 hp Nakajima NK9K-L "Homare" 24
radial engines with Hitachi 92 turbosuperchargers
and driving four-bladed propellers. The engines were cooled by counter-rotating fans positioned just inside the engine cowlings.
Defensive armament included power-operated nose, dorsal, ventral and tail turrets along with two free-swiveling machine guns at the beam positions