Battle damage increases the ships needed to maintain a forward force

Forward bases and resupply points could support Pacific operations, but major work might still require a destroyer to return to Pearl Harbor or farther. An illustrative three-ship cycle assigns one ship to operations, one to transit, and one to maintenance or training. Battle damage can remove a ship from that cycle before another is ready to replace it. An illustrative allowance of four, five, or six hulls accounts for battle damage as well as the normal availability cycle. These numbers illustrate reserve requirements without fixing a ratio for every deployment. The planning problem becomes larger when the fleet needs ten, twenty, or thirty destroyers available together.