How larger fleets absorb unexpected missions

Multiplying operational demand by three gives an initial fleet estimate, but larger fleets can use their ships more efficiently. Commercial fleet-management models often assume that a haulage company can hire vehicles or subcontract work when something goes wrong. Warship planners cannot count on that reserve of rentable ships. The examples give two available hulls from five ships, four from nine, and six from twelve. Availability can include a ship waiting dockside rather than already operating at sea. Larger numbers allow an urgent mission to draw from the returning or working-up group without disrupting the whole training and refit programme.