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Harbor pilots board incoming ships far offshore, climbing a rope ladder in all weather to guide vessels too large to —navigatenavigationnavigatingnavigated safely through narrow, current-swept channels. Their intimate knowledge of local tides and sandbanks cannot be replaced by satellite charts alone, since conditions —constantlyconstantconstancyconsistency shift with each storm. Consequently, most ports still require large ships to take on a pilot before —being grantedgrantinggrantgranted entry.