WASHINGTON — Two collisions between Navy destroyers and commercial vessels in the Western Pacific earlier this year were the result of a string of crew and basic navigational errors, the Navy’s top officer said in reports made public on Wednesday.

Seven sailors were killed in June when the destroyer Fitzgerald collided with a container ship near Japan. The collision in August of the John S. McCain — another destroyer, named after Senator John McCain’s father and grandfather — and an oil tanker while approaching Singapore left 10 sailors dead.

In the case of the Fitzgerald, the Navy determined in its latest reports that the crew and leadership on board failed to plan for safety, to adhere to sound navigation practices, to carry out basic watch practices, to properly use available navigation tools, and to respond effectively in a crisis.


“Many of the decisions made that led to this incident were the result of poor judgment and decision-making of the commanding officer,” the report concluded. “That said, no single person bears full responsibility for this incident. The crew was unprepared for the situation in which they found themselves through a lack of preparation, ineffective command and control, and deficiencies in training and preparations for navigation.”

In the case of the John S. McCain, the investigation concluded that the collision resulted from “a loss of situational awareness” while responding to mistakes in the operation of the ship’s steering and propulsion system while in highly trafficked waters.

“The collisions were avoidable,” Admiral John Richardson, the chief of naval operations, said in a summary of the two reports.

The release of the twin reports came a day after the Navy held closed-door briefings for lawmakers on Capitol Hill on its findings and recommendations and sent officers crisscrossing the country to brief family members of the sailors killed. A broader review of the Seventh Fleet’s pace of operations, training, equipment, and maintenance is set to be released on Thursday.