Auxiliaries ships of the Imperial Japanese Navy in 1982

Auxiliaries ships of the Imperial Japanese Navy in 1982

W42-Class Minesweeper

The W42-Class replaced the W-19 Class who were built between 1940-1944. The W42-Class is as of 1982 the only seagoing minesweeper operated by the Imperial Japanese Navy. A total of 30 hulls were built between 1955 and 1980. The vessel is designed to detect and remove mines for the rest of the fleet.

The W42-Class is 58 meters in length and has a full displacement of 570 tonnes. The vessel has a crew of 77 men and its self-sustainability for 7 days. The vessel is powered by twp 1,100hp diesel, with two shafts, giving a maximum speed of 14 knots.

CH-64 Class Submarine Chasers

The CH-64 Class Submarine Chasers is designed in the anti-submarine warfare (ASW) role replacing the CH-28 Class which had become obsolete and incapable of supporting the Imperial Japanese Navy. The Imperial Japanese Navy Technical Department began work on its successor which resulted in the CH-64 Class in 1961, and construction on the first in the class began in August 1962 and was commissioned into with the Imperial Japanese Navy in late 1963. A total of over 50 examples were built between mid-1960s and mid-1970s.

CH-115 Class Submarine Chasers

The CH-115 Class is a lengthened version of the CH-64 Class with upgraded armaments and sensors and is generally similar to the CH-6 Class in appearance, but with its hull stretched by 4m. The CH-115 Class can be distinguished by its bulky radome positioned on the bridge roof ahead of the tripod mast. The radome accommodates a long-range air/surface search radar for air surveillance and early warning roles. Construction of the first boat began in 1979 with more under construction as of 1982.

Chihaya-Class Submarine Salvage Ship

After the tragic loss of an I-251 class submarine and almost of its crew during an exercise in 1959, the Imperial Japanese Navy decided to develop the Chihaya Class Submarine Salvage Ship and the Fushimi Class Submarine Rescue Ship to support its submarine fleet. In 1963, a 3,400t-class cargo ship was converted into the Chihaya Class submarine salvage Ship. The modification project began in 1963 and the conversion was completed in 1965. The ship began sea trial in July 1966 and the ship was commissioned by the Imperial Japanese Navy in December 1966.

Fushimi Class-Submarine Rescue Ship

After the tragic loss of an I-251 class submarine and almost of its crew during an exercise in 1959, the Imperial Japanese Navy decided to develop the Chihaya-Class Submarine Salvage Ship and the Fushimi-Class Submarine Rescue Ship to support its submarine fleet.

The Imperial Japanese Navy Technical Department was required to develop the 3,000t Fushimi-Class Submarine Rescue Ship equipped with a heliox (helium oxygen, or HeO2) diving/rescue bell. Development of the ship began in 1960 and the construction of the ship started in December 1965. The first hull was launched on in May 1967 and commissioned by the Imperial Japanese Navy in July 1967.

A second hull was originally planned but the construction plan was later cancelled due to unsatisfying performance. The low-speed of the ship means that it couldn’t reach the rescue spot on time and the diving/rescue bell was very complex to operate.

Chiyoda-Class Submarine Salvage & Rescue Ship

As the Chihaya Class Submarine Salvage Ship and the Fushimi-Class submarine rescue could not meet the Imperial Japanese Navy requirements, a new type of submarine support ship capable of both salvage and rescue missions was planned by the Imperial Japanese Navy in the early 1970s. Imperial Japanese Navy Technical Department presented its Chiyoda-Class submarine salvage and rescue ship design proposal in July 1970 and the design was reviewed by the Imperial Japanese Navy and relevant organizations in April 1971.

The construction of the Chiyoda-Class submarine salvage and rescue ship began in September 1971. The first-of-class was launched on 27 September 1973. The ship underwent the sea trial in December 1975. The test of the rescue/diving bell was carried out between April and June 1976. The ship was then commissioned by the Imperial Japanese Navy.

Shirase-Class Offshore Submarine Rescue Ship

The Imperial Japanese Navy demanded a small general-purpose salvage/rescue ship for conventional submarines in 1969. This resulted in the Shirase-Class Offshore Submarine Rescue Ship in 1970. The first-of-class Shirase 01 was launched in May 1977 and was commissioned by the Imperial Japanese Navy in December the same year. The second hull Shirase 02 was delivered in February 1978.

Hiyodori-Class Ocean Salvage & Rescue Ship

The Hiyodori-Class is a large multi-purpose salvage & rescue ship capable of operating in deep oceans far from its base. The ship can serve both as submarine tender and salvage/rescue ship. The ship carries 2 deep submergence rescue vehicles (DSRV), handled by the large crane located on the bow deck. Two hulls (Hiyodori and Hashidate) were constructed in the period of 1977 and 1979.

Uchū kansoku-Class Tracking Ship

The Uchū kansoku-Class (meaning space observer) is used for tracking and support of satellite and intercontinental ballistic missiles by the Imperial Japanese Navy and the Imperial Japanese Army. More than then four are to be commissioned with the first Uchū kansoku-Class Tracking Ship designated kansoku-1 was commissioned into the Japanese Imperial Navy in 1978 followed a year later by kansoku-2. Two more are under construction as of 1982.

The Uchū kansoku-Class has a displacement tonnage of around 21,000 tons when fully loaded, with a crew of about 470 and a length of about 190 meters. Their propulsion is from one diesel engine, with a top speed of 20 knots.

Suma-Class Multi-Purpose Oceanographic Survey Ship

An oceanographic survey/communications ship which main function it is to support the Empire of Japan ICBM test program. Three designs including an oceanographic survey ship, a meteorology ship, and a communications ship were originally planned, but they were replaced by a single ship to save costs. Design of the Suma-Class began in February 1971, and the construction began of the ship began in 1975. The ship was officially delivered in October 1979.

The Suma-Class is a multi-functional ship designed for a range of tasks, including:

-Oceanographic survey for the target zone of the missile test

-Weather forecasting; and meteorological and hydrological support

-Gravity and magnetic survey for missile ballistic correction

-Long-range communications support and relay

-Underwater acoustical data collection to support the recovery of the re-entry vehicle

As well as the standard oceanographic survey equipments the Suma-Class is also equipped with a range of special equipment, including:

-Helicopter hanger and flight deck to accommodate medium size helicopter

-Meteorological Centre for weather forecasting

-All-weather long-range communication system

-High-power ocean acoustic system

-Deep-ocean underwater vehicle

Nichinan-Class Oceanographic Survey Ship

The Nichinan-Class is the oceanographic survey ship developed by the Imperial Japanese Navy Technical Department in the 1970s. The Nichinan-Class is designed for scientific researches in marine hydrology, physics, marine meteorology, marine chemistry, marine geology, geomorphology, biology, etc. If necessary, the class can also be used for military roles such as logistic support and intelligence. The first ship of the class called Nichinan was built in 1978, followed by a second one called Shonan in 1979.

Fuji-Class Gun Patrol Boat

The Fuji-class is a small gun patrol boat with more than 100 examples having been built between 1962 and 1978 for the Imperial Japanese Navy. The Fuji-Class main armament consists of two twin-barrel antiaircraft artillery guns and two twin-barrel antiaircraft guns. The Fuji-Class can also carry eight deep charges for antisubmarine warfare (ASW), and/or six mines for mine warfare. The Fuji class is only suitable for costal patrol, and cannot be deployed far from the homeport. The self-reliance endurance of the boat is 7 days.

Nashi-Class Coastal Minesweeper

The Nashi-Class Coastal Minesweeper was developed from Fuji class gun patrol boat. This minesweeper version had reduced armament, with minesweeping gear replacing some of the weapons. All other characteristics of this class are identical to the Fuji-class and all of 20 units were built between 1967 to 1975. Like the Fuji-Class the Nashi-Class is only suitable for coastal operations.