Convoy planning at the geostrategic level starts with the quantity of supplies that must arrive. Expected shipping losses then determine how much cargo and how many ships need to be sent. The calculation accepts that losses will occur while trying to keep deliveries sufficient for the war effort. Replacing hulls is only part of the problem, because ships must also be completed and crewed before they can carry supplies. A transport system with no margin beyond immediate requirements cannot absorb those interruptions.
Notable Point · 52:32-58:28
Convoy strategy is a problem of usable throughput
At the geostrategic level, convoy success depends on how much cargo arrives and how quickly replacement ships can be completed and crewed.