using actual careers of u-boat aces as an example (from uboat.net)... i averaged the total number of days for career length, then i averaged the number of those total dayswhich were spent at sea. by doing this i was able to determine an estimated average number of days spent in port.
i came up with what i personally consider to be an accurate time of anywhere between 20 and 30 days in port.
this is based on VII aces
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