Whipping can contribute to increased fatigue and extreme loading of container ships, and guidelines have been made available by the leading class societies.
Reports concerning the hogging collapse of MSC Napoli and MOL Comfort suggest that whipping contributed. The accidents happened in moderate to small storms.
Model tests of three container ships have been carried out in different sea states under realistic assumptions. Preliminary extrapolation of the measured data suggested that moderate storms are dimensioning when whipping is included due to higher maximum speed in moderate storms.
This paper considers various extrapolation methods to investigate the uncertainty in the extrapolation methods and to see if all methods confirm that the moderate storms are dimensioning.