The Nakajima G8N Renzan (連山, "Mountain Range") was a four-engined long-range bomber designed for use by the Imperial Japanese Navy. The Navy designation was "Type 18 land-based attack aircraft" (十八試陸上攻撃機); the Allied code name was "Rita".
Design and development
In 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).[1]
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 driving four-bladed propellers. The engines were cooled by counter-rotating fans positioned just inside the engine cowlings.[1] Defensive armament included power-operated nose, dorsal, ventral and tail turrets along with two free-swiveling machine guns at the beam positions.[2]
Operational history
A captured G8N painted in United States Army Air Forces markings with a C-45 and T-6
The initial prototype was completed in October 1944 and delivered to the Navy for testing in January 1945, a year after the Navy ordered development to start. Three further examples were completed by June 1945, with the third prototype being destroyed on the ground by US carrier aircraft.[2]
Other than minor problems with the turbosuperchargers, the Renzan performed satisfactorily and the Navy hoped to have a total of 16 prototypes and 48 production-version G8N1s assembled by September 1945. But the worsening war situation and a critical shortage of light aluminium alloys led to the project's cancellation in June.[2]
One proposed variant was the G8N2 Renzan-Kai Model 22, powered by four 2,200 hp Mitsubishi MK9A radial engines and modified to accept attachment of the air-launched Ohka Type 33 Special Attack Bomber.[2]
Just before Japan's surrender in August 1945 consideration was also briefly given to producing an all-steel version of the aircraft, to be designated G8N3 Renzan-Kai Model 23, but the cessation of hostilities precluded any further development.[2]
After the war, one prototype was taken to the United States[3][4] and scrapped after testing. None are in existence today.
Variants
A Nakajima G8N1 (left) and a G5N1 (right) photographed by an American reconnaissance flight.
G8N1 : Four-engine heavy bomber. Production version.
G8N2 : Modified to carry Ohka Type 33 Special Attack Bomber. Four Mitsubishi MK9A radial engines.
Collier, Basil. Japanese Aircraft of World War II. New York: Mayflower Books, 1979. ISBN0-8317-5137-1.
Francillon, René J. (1979). Japanese Aircraft of the Pacific War (2nd ed.). London: Putnam & Company Ltd. ISBN0-370-30251-6.
Thorpe, Donald W. (1977). Japanese Naval Air Force Camouflage and Markings World War II. Fallbrook, California: Aero Publishers, Inc. ISBN0-8168-6583-3.
Unknown authors. Famous Airplanes of the World: Nakajima Shinzan / Renzan (Volume 11, no.146). Japan: Bunrin-Do, Nov. 1984.
1 X as second letter is for experimental aircraft or imported technology demonstrators not intended for service,
2 Hyphenated trailing letter (-J, -K, -L, -N or -S) denotes design modified for secondary role, 3 Possibly incorrect designation, but used in many sources
With some exceptions for rockets, jets and repurposed aircraft, names chosen were for: 1. Winds, 2. Lightning, 3. Nighttime lights, 4. Mountains, 5. Stars/constellations, 6. Seas, 7. Clouds, 8. Plants, 9. Skies, 10. Landscapes, and 11. Flowers. Published translations disagree, and many are simplified, especially for plants, where the Japanese referred to a specific variety and the common translations only to the broader type.
