Longitudinal motion characteristics of a ship according to the location

In head sea , a ship has mainly the longitudinal motion such as vertical acceleration and pitch . In that case ,the motion characteristics of a ship will have changed as the location different from each of place verticallyand horizontally on board . The author carried out an experiment about the ship ’s vertical acceleration andpitch according to the location for the head sea , and analyzed the data with the aid of the statistical andspectral analyzing method to get the motion characteristics of the vessels . The response of verticalacceleration and pitch not deeply depend on the decks vertically , but displayed the relative big differentvalue horizontally even if same deck . The biggest response of vertical acceleration and pitch among theaccommodations was shown at scientist room , but the value of it not reached to the minimum requirement ofISO 2631-1 for working on board .Keywords: Head sea , Longitudinal motion , Vertical Acceleration , Pitch , Motion characteristics .