The skipper of the USS Fitzgerald and two top sailors from the ship's leadership team will be relieved for losing "situational awareness" in the hours leading up to a fatal June collision that left seven sailors dead, the service's deputy chief said Thursday.

Adm. Bill Moran, the deputy chief of naval operations, said that Vice Adm. Joseph Aucoin, head of the Navy's 7th Fleet, plans to relieve Cmdr. Bryce Benson for cause. On Thursday, the Navy released a preliminary report on the June 17 collision between the Fitzgerald and the freighter ACX Crystal off the coast of Japan.

About a dozen sailors in all face some punishment, including all of the destroyer's watch. Further sanctions are possible, Moran said.

"Clearly at some point, the bridge team lost situational awareness," Moran said.

Aucoin acted swiftly because the investigation indicated serious mistakes were made by the crew, Moran said. The Navy has lost confidence in the sailors being relieved.

Collisions should never happen, Moran said. "We got it wrong."

The report released Thursday details the frantic efforts to account for all the sailors in the darkened, flooding ship, keep her afloat, and rescue the ship’s commander who dangled outside his crumpled cabin. The harrowing moments and hours after the collision — and the heroism that saved the lives of all but seven of the 35 sailors in Berthing 2 — are recounted in the report.

Seconds after the ACX Crystal plowed into the starboard side of the Navy’s guided missile destroyer at 1:30 a.m., on June 17, seawater gushed through a 13-foot-by-17-foot gash, knocking some from their beds and threatening to drown all 35 sailors in the compartment.

“Water on deck!” sailors shouted. “Get out!”

“The crew of the Fitzgerald fought hard in the dark of night to save their ship,” wrote Rear Adm. C.F. Williams, commander of Carrier Strike Group Five. Williams’ preliminary report looks at the injuries and deaths that resulted from the crash.

The Fitzgerald, with a crew of about 300 sailors, was about 56 nautical miles southwest of Yokosuka, Japan, at the time of the collision. The sea was calm, and the moon shone through broken clouds. The Fitzgerald was dark but for navigation lights, and red bulbs inside the ship.

The Crystal is a far larger ship at 728 feet and 29,000 tons, compared with the Fitzgerald’s 505 feet and 9,000 tons. The port side of the Crystal’s bow slammed into the Fitzgerald above the waterline, and the bulb-like bow below the surface crunched into the Fitzgerald near Berthing 2.

Flooding in Berthing 2

Berthing 2 held 42 beds in stacks of three bunks, a bathroom, and a lounge area with sofas, chairs and a television. After the collision, “nothing separated Berthing 2 from the onrushing sea, allowing a great volume of water to enter Berthing 2 very quickly.”

The Fitzgerald rocked violently, settling into a 7-degree list to her starboard side.

“One sailor saw another knocked out of his rack by water,” according to the report. “Others began waking up shipmates who had slept through the initial impact. At least one sailor had to be pulled from his rack and into the water before he woke up.”

Within a minute, the compartment had flooded and the water rose. Mattresses, furniture and an exercise bike floated in the aisles. The tilting ship complicated the escape, and the water was neck high by the time many had reached the ladder to climb to safety.

"You can just imagine the confusion and how difficult it was to escape Berthing Compartment 2," Moran said.

As the water forced them to the top of the stairs, two sailors reached into the dark water and fished two more shipmates out. The last rescued sailor had been in the bathroom at the time of the crash. The sailors “pulled him from the water, red-faced and with bloodshot eyes. He reported he was taking is final breath before being saved, he was already submerged and breathed in water.”

The seven sailors who drowned were nearest the gash, “directly in the path of the onrushing water.”

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Sailors rushed to seal off flooding to keep the Fitzgerald afloat as water gushed through the gaping hole. Large pipes that carry seawater to fight fires also ruptured, inundating other areas.

The Crystal slammed into Benson's cabin, crumpling his quarters. Communications outside the ship were severed. Power was lost in the front of the Fitzgerald.

After the crash, the Fitzgerald crew changed the ship's lighting at the mast to one red light over another. That configuration, "red over red," is "the international lighting scheme that indicates a ship that is not under command," the report notes.

Benson was in his cabin when the collision occurred, and the crash trapped him. It took five sailors swinging a sledgehammer and kettle bell and hurling their bodies against his door to break through. A junior officer and two chief petty officers yanked debris out of the cabin and crawled in.

"The skin of the ship and outer bulkhead were gone and the night sky could be seen through the hanging wires and ripped steel," the report says. "The rescue team tied themselves together with a belt in order to create a makeshift harness as they retrieved (Benson), who was hanging from the side of the ship."

A helicopter whisked him ashore to a hospital. He was treated and released the next day.

The Fitzgerald, still listing, crept back to Yokosuka. Navy divers recovered the bodies of the seven drowned sailors on June 18.