The Special number 3 light tank Ku-Ro (特三号戦車 クロ) (also known as the "So-Ra"
) was an experimental
Japanese
Japanese may refer to:
* Something from or related to Japan, an island country in East Asia
* Japanese language, spoken mainly in Japan
* Japanese people, the ethnic group that identifies with Japan through ancestry or culture
** Japanese diaspor ...
winged light tank
A light tank is a tank variant initially designed for rapid movements in and out of combat, to outmaneuver heavier tanks. It is smaller in size with thinner armor and a less powerful main gun, tailored for better tactical mobility and ease of ...
project, developed during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
.
History and development
In the Fall of 1943, the
Imperial Japanese Army
The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...
's
Teishin Shudan
was a Japanese special forces/airborne unit during World War II. The unit was a division-level force, and was part of the Imperial Japanese Army Air Force (IJAAF). The ''Teishin'' units were therefore distinct from the marine parachute units of ...
formed the 1st Glider Tank Troop. Before the 1st Glider Troop was established, the only heavy support available to Japan's
airborne
Airborne or Airborn may refer to:
Arts, entertainment, and media
Films
* ''Airborne'' (1962 film), a 1962 American film directed by James Landis
* ''Airborne'' (1993 film), a comedy–drama film
* ''Airborne'' (1998 film), an action film sta ...
infantry was provided by the
Kokusai Ku-8
The (Kokusai Army Type 4 Special Transport Glider) was a Japanese military glider used during the Second World War.
Design and development
Design of the Ku-8-II began in December 1941, the glider was essentially a Kokusai Ki-59, with the engin ...
. This
military glider
Military gliders (an offshoot of common gliders) have been used by the militaries of various countries for carrying troops (glider infantry) and heavy equipment to a combat zone, mainly during the Second World War. These engineless aircraft were ...
was able to transport the
Type 94 and
Type 94 75 mm
mountain gun
Mountain guns are artillery pieces designed for use in mountain warfare and areas where usual wheeled transport is not possible. They are generally capable of being taken apart to make smaller loads for transport by horses, humans, mules, tractor ...
s, but these infantry support guns lacked the mobility and anti-tank capabilities required by Japan's paratroopers. The solution to this problem was to develop a glider-portable light tank, but the existing Ku-8 glider was not capable of supporting the weight of a vehicle as large as a tank. So in 1943 and into 1944 the Armoured Army Headquarters (army aviation headquarters) and the Fourth Army Institute of Technology collaborated on a new concept to fill this role, a flying tank. A small tank that could be towed on a
glider
Glider may refer to:
Aircraft and transport Aircraft
* Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight
** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of glidin ...
by a powered aircraft and then released and glide down to the battlefield along with paratroopers. The tank would detach its wings after landing
and then be able to provide armour support to the infantry. Rather than using an existing tank or glider design, it was decided that a new tank and new glider should be developed. Work on developing the glider was given to
Maeda Iron Works Company, while designing and building of the prototype was given to
Mitsubishi
The is a group of autonomous Japanese multinational companies in a variety of industries.
Founded by Yatarō Iwasaki in 1870, the Mitsubishi Group historically descended from the Mitsubishi zaibatsu, a unified company which existed from 1870 ...
.
Design
Mitsubishi based the tank on their
Type 98 Ke-Ni light tank
The or Type 98A Ke-Ni Ko (also known as Type 98 Chi-Ni light tank) was designed to replace the Imperial Japanese Army's Type 95 Ha-Go light tank, Japan's most numerous armored fighting vehicle during World War II. Although designed before World ...
. The weight was reduced to 2.9 tons from 7.2 tons and the crew was brought down from 3 to 2. A single prototype was built and named the "Special number 3 light tank Ku-Ro". The commander sat in the turret and acted as both gunner and loader. The driver's position was located in the chassis. The turret was rear-mounted and housed the tank's only weapon, a
Type 100 37 mm tank gun
The or Type 98A Ke-Ni Ko (also known as Type 98 Chi-Ni light tank) was designed to replace the Imperial Japanese Army's Type 95 Ha-Go light tank, Japan's most numerous armored fighting vehicle during World War II. Although designed before Wor ...
, the same used by the Ke-Ni. There was no coaxial or hull mounted machine gun. There were plans to mount either a flamethrower or 7.7 mm
Type 97 machine gun in place of the tank's 37 mm gun. The glider developed for the Ku-Ro was the
Maeda Ku-6 a 700 kg
twin boom
A twin-boom aircraft is characterised by two longitudinal booms (extended nacelle-like bodies). The booms may contain ancillary items such as fuel tanks and/or provide a supporting structure for other items. Typically, twin tailbooms support ...
craft that was specially designed to fit the tank. When mounted in the Ku-6 glider, the Ku-Ro had a wingspan of 22 m, a length of 12.8 m and a total weight of 4.2 tons. The glider was designed to be towed behind a
Mitsubishi Ki-21
The (Allied reporting name: "Sally" /"Gwen") was a Japanese heavy bomber during World War II. It began operations during the Second Sino-Japanese War participating in the Nomonhan Incident, and in the first stages of the Pacific War, including ...
medium bomber
A medium bomber is a military bomber Fixed-wing aircraft, aircraft designed to operate with medium-sized Aerial bomb, bombloads over medium Range (aeronautics), range distances; the name serves to distinguish this type from larger heavy bombe ...
. The
tracks of the tank were unable to match Ki-21's take-off and landing speeds and since taking-off and landing would cause a great amount of damage from friction to the tracks, a pair of detachable
ski
A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than wide and characteristically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partial ...
s were made part of the glider. The glider, after being launched and landing could quickly be disassembled and removed from the Ku-Ro tank.
By 1945 the project was cancelled.
This was caused by a combination of technical problems, related to the poor manoeuvrability of the glider and stress on the tank, and the changing nature of the war for Japan. The
Pacific War
The Pacific War, sometimes called the Asia–Pacific War, was the theater of World War II that was fought in Asia, the Pacific Ocean, the Indian Ocean, and Oceania. It was geographically the largest theater of the war, including the vast ...
was going poorly for Japan by 1944. The Japanese had lost
air supremacy
Aerial supremacy (also air superiority) is the degree to which a side in a conflict holds control of air power over opposing forces. There are levels of control of the air in aerial warfare. Control of the air is the aerial equivalent of com ...
to the
United States Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal ...
and the chances of any large Japanese aircraft towing a glider being intercepted and shot down were very high and would mean not only the loss of the aircraft but the tank, as well. As with many innovative weapons projects launched by Japan in the final years of the war, production could not advance beyond the prototype stage due to material shortages, and the loss of Japan's industrial infrastructure to the
Allied bombing of Japan.
See also
*
Winged tank
Tanks with glider wings were the subject of several unsuccessful experiments in the 20th century. It was intended that these could be towed behind, or carried under, an airplane, to glide into a battlefield, in support of infantry forces.
In war, ...
*
Antonov A-40
The Antonov A-40 ''Krylya Tanka'' (russian: крылья танка, meaning "tank wings") was a Soviet attempt to allow a tank to glide onto a battlefield after being towed aloft by an airplane, to support airborne forces or partisans.Winc ...
*
Light Tank Mk VII Tetrarch
The Light Tank Mk VII (A17), also known as the Tetrarch, was a British light tank produced by Vickers-Armstrongs in the late 1930s and used during the Second World War. The Tetrarch was the latest in the line of light tanks built by the company ...
*
Japanese tanks of World War II
The Imperial Japanese Army (IJA) initially purchased foreign tanks for evaluation during World War I, and began developing its own indigenous designs during the late 1920s.
Due to the war with China, Japan produced a large number of tanks. Alt ...
*
List of engines and weapons used on Japanese tanks during World War II
*
List of Japanese armoured fighting vehicles of World War II
Notes
References
* 木俣滋郎『幻の秘密兵器 恐るべき先駆的技術の集大成』廣済堂出版 1977年
(後に光人社NF文庫から再版 1998年 )
*
*
External links
Historic Wings
{{WWIIJapaneseAFVs
Light tanks of Japan
Number 3 Ku-Ro
Experimental and prototype tanks
History of the tank