Running slower than optimal speed uses too much fuel.
10-11 knots is ideal. Assuming you tank up at Midway outbound, you should egt to Japan with 3/4 of a tank left.
Regardless, I think there should be a sort of "abandon ship" or "Assistance requested" button. Might be as simple as this, you send a status report, and if your fuel state is zero, or if your engines are destroyed, or if you have no rudder, it rolls a die and tells you about being picked up by a friendly sub, or there is nothing they can do (based on your position).
tater
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