Five of the seven Navy sailors who died aboard the guided-missile destroyer USS “Fitzgerald” when it collided with the “ACX Crystal” off the East coast of Japan may have been almost instantly incapacitated and died quickly, according to a preliminary Navy analysis. That assessment was based on an examination of the point of impact and the berths in which the sailors were likely sleeping.

The Navy was trying to corroborate accounts which suggested that the two sailors who weren’t almost instantly incapacitated attempted to help the other five escape the incoming water. But at some point the ship somehow lost communication, with the two sailors and they also perished, according to the official.

All seven were found dead in the flooded area. G The collision occurred very close to the cabin of Cmdr. Bryce Benson, and he was briefly unable to get out. The crew helped him to the bridge, but he was so badly injured that he had to be medevaced off the ship and the second in command took over.

The US Navy, the US Coast Guard, and Japanese naval and maritime authorities were all conducting investigations. An early assessment suggested the container ship might have been on some type of autopilot system at the time of the collision which does not explain how and why the crew of the USS “Fitzgerald” did not see the other ship coming, or why they were unable to maneuver away from it. Initial reports suggest that the collision occurred at 1:30 a.m., but the container ship crew did not automatically realize it had happened.

The container ship turned back, and it appeared the collision was then formally reported around 2:20 a.m. To help determine what happened, investigators will download radar data from the ship’s Aegis weapons system, which records routine details on position, course, speed and any nearby ships or aircraft. Navigation and radar data will also be gathered from the cargo ship. Another factor being examined was the impact of the destruction of the “Fitzgerald”‘s communications gear on the ability of the crew to call back to shore to inform commanders they needed help. Preliminary analysis indicated the collision occurred where the ship’s communication nodes were housed and the crew had to use satellite based cell phones to communicate both on board and back to shore.