Ocean research vessel Kaimei will join the search for a F-35 stealth fighter in northern Japan. The jet went down in waters off Aomori Prefecture on April 9.
Search operations for the pilot and most parts of the aircraft are running into difficulties as the ocean in the area is up to 1,500 meters deep.
Defense Minister Takeshi Iwaya told reporters on Tuesday that the Japan Agency for Marine-Earth Science and Technology's vessel is very capable of surveying the sea bottom. He said with its help he hopes to find the plane as soon as possible.
The United States is also planning to send a ship by the end of the month that has exceptional search capability.
The stealth technology used in the F-35 aircraft is highly classified. The two countries are working together to determine the cause of the crash.