 Critical to Pan Am's success as an airline was the proficiency of its flight crews, who were rigorously trained in long-distance flight, seaplane anchorage and berthing operations, over-water navigation, radio procedure, aircraft repair, and marine tides.During the day, use of the compass while judging drift from sea currents was normal procedure; at night, all flight crews were trained to use celestial navigation.In bad weather, pilots used dead reckoning and timed turns, making successful landings at fogged-in harbors by landing out to sea, then taxiing the plane into port.