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Every effort is made to get somebody medical care while inside the submarine. However, if a sailor does manage to die during operations, the Navy only has a few options to store the body.
Ideally, the submarines would surface to allow the body to be airlifted via a helicopter. Though it is ideal, it’s not always the case – especially if the submarine is conducting operations.
In these cases, the body of the deceased will be placed in a body bag and stored in a freezer – the same one that stores the food for the crew. The body would remain inside the freezer until arrangements could be made to evacuate the deceased.
If a commanding officer dies, the executive officer takes their place while the next highest-ranking officer replaces the XO.