The jet crashed on April 9 during an Air Self-Defense Force night exercise after having taken off from Misawa Air Base in Aomori, sources report. The pilot of the stealth jet is also missing.
Now, Japan and the US are worried about the consequences of the aircraft being discovered by other countries. They specifically believe that such a development could be a major military intelligence breach.
In addition, science minister Masahiko Shibayama told that the research vessel Kaimei, which the Japan Agency for Marine-Earth Science and Technology owns, will also join in the operation, after a request from the Defense Ministry.
The ship has a remotely operated vehicle, able to observe up to a depth of about 3,000 meters.