Research Vessel


Research Vessel TANSEI MARU retired on January 31, 2013.


TANSEI MARU was transferred from the University of Tokyo's Ocean Research Institute in 2004, coinciding with the inauguration of JAMSTEC as an independently administered institution. The vessel is employed in a wide range of fundamental ocean research operations, mainly in the seas surrounding Japan, including Sagami Bay, Suruga Bay, Kumano-nada, and off Sanriku.


Excellent operability

In order to provide the high-precision level of operability and course-keeping characteristics required during observations, TANSEI MARU is equipped with an automatic bow steadying device on its bow thrusters. The vessel's engines have also been constructed to allow a constant speed to be maintained, whether fast or slow, during observations.

High-precision ship positioning

TANSEI MARU is the first vessel in its class to be fitted with a hybrid navigation system. This navigation system provides an exemplary level of ship positioning precision, essential in search cruises, and this allows TANSEI-MARU to provide the high level of performance required of ocean research vessels.

Multipurpose research rooms

Research space aboard TANSEI MARU is conveniently located near the center of the vessel, and direct access to the aft observation and operations deck means that tasks can be carried out with a high level of efficiency. The research space, which covers approximately 53 m2, is composed of a dry research room located at the bow of the ship (approximately 21 m2), a semi-dry research room located in the center of the vessel (approximately 20 m2, including a clean room), and a wet research room located towards the rear of the ship (approximately 12 m2). These rooms are not partitioned, however, and can be used in a multipurpose style by shifting the desks and other equipment around, thereby adapting the space to research activities in a variety of fields.

Principal specifications

Length51.0 m
Beam9.2 m
Depth4.2 m
Draft5.0 m
Gross tonnage610 tons
Cruising speed11.5 knots
Range6,200 nautical miles
Accommodation38 (23crew, 15 research personnel)
Main propulsion system4-cycle diesel engines: 750 ps × 2 (2 units, single shaft)