On two solutions of fifth order Stokes waves

It has been demonstrated numerically that there are two real solutions of the dispersion relation of fifth order Stokes waves given by Skjelbreia and Hendrickson (Fifth order gravity wave theory, Proc. 7th Coastal Engng Conf., The Hague, 1960, pp. 184-196) which is widely used and recommended in offshore codes of practice. The additional solution predicts a triple crested wave and it always seems to coexist with the conventionally accepted solution. Some properties of this solution are given. © 1995.