The Ehime Maru was a Japanese fishery high school training ship with 35 people on board, including students and crew members, engaged in a program designed to educate future fishermen. On the morning of February 9, 2001, the USS Greeneville, a Los Angeles-class attack submarine, was conducting a demonstration for several civilian guests aboard when it collided with the Ehime Maru near Diamond Head in Pearl Harbor, Hawaii. This unfortunate event occurred during the Greeneville's surfacing maneuver, which involved rapid ascent and an inadvertent failure to adequately observe surrounding maritime traffic. The impact occurred at approximately 1:46 PM local time, leading to significant damage to the Ehime Maru.In the aftermath of the collision, emergency measures were immediately deployed. The submarine was capable of surfacing quickly and was able to assist with rescue efforts, but the tragedy had already unfolded with the loss of nine lives, including high school students on board the training vessel. The incident drew international attention, prompting investigations by both the U.S. Navy and the Japanese government to understand the precise circumstances and to evaluate the training protocols in place on both vessels. The Greeneville sustained considerable damage, leading to approximately $2 million in repairs, and the accident raised questions regarding naval training exercises and operational safety protocols in the U.S. Navy.The collision led to heightened scrutiny over the conduct of Navy personnel during training exercises and prompted discussions around the adequacy of training in the management of complex maritime situations. The U.S. Navy faced criticism over the events leading up to the collision, and the incident propelled discussions about deeper collaboration and communication between the U.S. Navy and its allies to ensure maritime safety.