The Amphibious Truck "Su-Ki" was a

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 World War II by country, vast majority of the world's countries—including all of the great power ...

Japanese military vehicle manufactured by the

Toyota is a Japanese multinational automotive manufacturer headquartered in Toyota City, Aichi, Japan. It was founded by Kiichiro Toyoda and incorporated on . Toyota is one of the largest automobile manufacturers in the world, producing about 10 ...

Motor Co., Ltd, similar in concept to the GMC DUKW. It entered service in 1943 and was used by Japanese forces in the Pacific during World War II.

Background

The Guadalcanal campaign demonstrated to 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 ...

(IJA) the need for vehicles that could transport supplies directly from cargo ships to the shore and beyond. While the Japanese Imperial Navy had several vehicles (including the Type 4 Ka-Tsu amphibious landing craft) the Army had no such vehicles. The Su-Ki was a stop-gap measure until larger and better designed vehicles could be developed.

Design

The vehicle was an amphibious truck based on the Toyota KCY (To-Ki) 4×4 truck. The engine was a

inline-six The straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine bala ...

3.4l Type B engine with power being transmitted to the rear axle via

Hotchkiss drive The Hotchkiss drive is a shaft drive form of power transmission. It was the dominant means for front-engine, rear-wheel drive layout cars in the 20th century. The name comes from the French automobile manufacturer Hotchkiss, although other maker ...

and water propulsion was via PTO drive prop. It could operate in either 2-wheel or 4-wheel drive. The body was made up of steel and had a "boat shaped" hull, with the hull and other body panels having a 5mm thickness, primarily for protection against rough seas and small arms. The Su-Ki had an unladen weight of 6.4

tonnes The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United States ...

and a carrying capacity of 2 tonnes. The cargo was carried on the rear deck with tall sides and an open top, loaded at the rear via a loading ramp. Between November 1943 and August 1944, 198 Su-Ki trucks were produced by Toyota.

Usage

Su-Ki amphibious trucks were used by the Japanese military forces on Pacific islands during

. The vehicle saw use in the Solomon and Gilbert Island campaigns, as well as operations on

Ellice Island Tuvalu ( or ; formerly known as the Ellice Islands) is an island country and microstate in the Polynesian subregion of Oceania in the Pacific Ocean. Its islands are situated about midway between Hawaii and Australia. They lie east-northeas ...

. The experience of using the vehicle in operations, especially on Ellice, highlighted the need for better design and Toyota developed the experimental "LVT" from the Su-Ki.

Survivors

The only known survivor is a rusted hulk that remains on the

Micronesia Micronesia (, ) is a subregion of Oceania, consisting of about 2,000 small islands in the western Pacific Ocean. It has a close shared cultural history with three other island regions: the Philippines to the west, Polynesia to the east, and ...

island of

Ponape Ponape may refer to: *Pohnpei Pohnpei "upon (''pohn'') a stone altar (''pei'')" (formerly known as Ponape or Ascension, Proto-Chuukic-Pohnpeic: ''*Fawo ni pei)'' is an island of the Senyavin Islands which are part of the larger Caroline Isla ...

. The island was not invaded by the Allies in combat, and during post-war occupation the Su-Ki (and other equipment) was not worth the effort to remove from the island.

References

Notes

Bibliography

* * {{Toyota Motor Corporation Military trucks Soft-skinned vehicles Toyota vehicles Amphibious military vehicles World War II vehicles of Japan Military vehicles introduced from 1940 to 1944