Contents

JSChihaya

JSChihaya on 9 September 2019
History
Japan
Name	Chihaya (ちはや)
Namesake	Chihaya
Ordered	1996
Builder	Mitsui, Tamano
Laid down	13 October 1997
Launched	8 October 1998
Commissioned	17 March 2000
Homeport	Kure
Identification	MMSI number: 431999637 Callsign: JSLT Pennant number: ASR-403
Status	Active
Class overview
Preceded by	Chiyoda class (1983)
Succeeded by	Chiyoda class (2016)
General characteristics
Type	Submarine rescue ship
Displacement	5,540–6,900 long tons (5,629–7,011 t) full load
Length	128.0 m (419 ft 11 in)
Beam	20.0 m (65 ft 7 in)
Draught	9.0 m (29 ft 6 in)
Depth	5.1 m (16 ft 9 in)
Propulsion	2 × diesel engines (16,000 hp, 12,000 kW)
Speed	21 knots (39 km/h; 24 mph)
Range	6,000 nmi (11,000 km; 6,900 mi) at 13 kn (24 km/h; 15 mph)
Boats & landing craft carried	1x deep-submergence rescue vehicle (DSRV) 2 x 11 m (36 ft) boats 1 x unmanned underwater vehicle (ROV) 1 x deep sea submersible (DDS)
Complement	125
Sensors and processing systems	2 x sonar AN/SQQ-25 (J) AN/SQS-36D (J) Atmospheric pressure diving device Automatic ship position holding device (DPS)
Aviation facilities	Helipad

JSChihaya (ASR-403) is a submarine rescue shipofJapan Maritime Self-Defense Force.

Development and design[edit]

She was built as a replacement for the dilapidated JDS Fushimi. In terms of design, it is said to be an expanded and improved version of the submarine rescue mother ship JS Chiyoda, and while abolishing the submarine mother ship function, it is strengthening medical equipment.^[1]

For DSRV operation, the basic configuration of having a moon pool in the center of the hull is the same as the 56AS, but the poop deck has been extended to the vicinity of the bridge structure, and the standard displacement has been increased by 1,800 tons. As a result, the equipment that was previously stored in the exposed part can now be accommodated inside the ship. In addition, attention was paid to high-speed cruising ability so that the vessel can quickly advance to the distress site, a bulbous bow was adopted to reduce wave-making resistance, and a ship bottom closing device was installed at the bottom of the center well. This is a method of opening and closing the closing plate divided into two by hydraulic pressure, and structures such as a sliding type and an inward opening type were examined, but due to the certainty required for the mission of rescue, the double door method by opening outward was adopted.

The main engine is equipped with two Mitsui Engineering & Shipbuilding 12V42M-A diesel engines. This is the same series as the in-line 8-cylinder engine that was the main engine in Chiyoda, but the output was increased by using a V-type 12-cylinder engine. As a propulsion device, in addition to two variable pitch propeller axes, two side thrusters are provided on the bow and stern. Like Chiyoda, they are equipped with a dynamic positioning system (DPS), which allows them to stand still at a point on the ocean.

Construction and career[edit]

Chihaya was laid down on 13 October 1997 at Mitsui Engineering and Shipbuilding, Tamano and launched on 8 October 1998. The vessel was commissioned on 17 March 2000.

The government, which received a request from Ehime Prefecture to search for survivors of the Ehime Maru incident that occurred on February 10, 2001, requested the Defense Agency respond. Chihaya began searching in August 2001.^[2][3]

The ship participated in the International Submarine Rescue Training Pacific Reach 2002 held in April 2002. In addition to successful operations despite stormy weather, the DSRV succeeded not only in its originally planned soft mate (arrival at the sunken submarine), but also in its hard mate (opening the hatch, more practical rescue training). At this point, the transport helicopter MH-53E Sea Dragon had succeeded in landing training.

In May 2008, a member of the explosives disposal corps on board set a record of 450 metres (1,480 ft) in depth due to saturated diving, setting the second highest (at that time) record in the world after 534 m (1,752 ft) in France.

In response to the Great East Japan Earthquake caused by the Tohoku-Pacific Ocean Earthquake that occurred on March 11, 2011, the ship was dispatched off Sanriku as part of the disaster relief. Chihaya was engaged in this duty from June 26 to July 3.

From July 13, 2018, she provided support in response to the flooding in July 2018.

References[edit]

Wikimedia Commons has media related to JS Chihaya (ASR-403).