By Ryan Browne

(CNN) -- The Chief of Naval Operations, US Navy Adm. John Richardson, took responsibility for what he called the "systemic issues" that contributed to recent fatal collisions involving two warships while announcing sweeping changes in order to improve standards.

"These accidents were preventable," Richardson told reporters Thursday during a briefing at the Pentagon following the release of a comprehensive review of the Japan-based 7th Fleet's operations aimed at preventing future mishaps.

Asked if he personally bore responsibility for the accidents, which cost the lives of 17 sailors, in his role, Richardson answered: "As the CNO, I own this."

"I feel responsible for this," Richardson later added while saying he thought he still retained the confidence of the sailors and the fleet.

Richardson said that some of the systemic issues uncovered were due in part to the Japan-based force's need to conduct multiple types of missions with limited resources.

"The comprehensive review found that over a sustained period of time, rising pressure to meet operational demands led those in command to rationalize declining standards," he said.

"Standards in fundamental seamanship and watch standing skills, teamwork, operational safety assessment and a professional culture," suffered as a result, according to Richardson.

One such example of a decline in standards was evidenced during the collision of the USS John S. McCain, where the crew manning the control console did not know how to properly operate it.

The comprehensive review, which was led by and included senior naval officers as well as civilians from outside the military, recommended a series of sweeping changes.

The recommendations included new processes for scheduling ships, "ready for sea" assessments for all Japan-based ships, disseminating lessons learned from "near misses," and ensuring that ships routinely, actively transmit on their automatic identification system to prevent coalitions.

Other changes have already been mandated, including ensuring that sailors aboard warships get adequate sleep.

"Fatigue did play a role," Richardson said, saying that new measures would be put in place to ensure that sailors were able to get six to eight hours of sleep every 24 hours.

While the review was confined to the 7th Fleet, Richardson said many of its findings would be pushed out to other naval commands.

Richardson was also asked if the Navy had a cultural problem where commanders were too willing to take on missions despite knowing that their ships were not fully ready.

"The can-do aspect of our Navy is something that we want to preserve. This bottom-up, effusive enthusiasm to get things done," Richardson said, but added, "when that turns around and becomes a sense of sort of a, 'must do, I've got to go out at any cost,' this is when it becomes toxic."

The-CNN-Wire

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