Human Factors and Watch Design

For centuries watch schedules aboard ships have been set by tradition. Beyond the most elementary accomodation, the operating characteristics and natural limits of mariners themselves have had little place in determining these sehedules. In this paper a number of watch schedules, existing and novel, are examined in light of the findings of human engineering with regard to circadian rhythms. Suggestions are made for ship operators to improve efficiency and effectiveness through manipulation of watch schedules.