Vassilopoulos and Mandel 



Fr = 0.25 _ 



+150 



+ 100 



H+ 50 S 



uj 



a: 



^ 



LlI 



o 



- 50 ~ 



* 



CO 



-100 

 -150 



Fig. 27 - Model D in directly ahead seas, heaving 

 non-dimensional amplitude and phase angle vs 

 wavelength to shiplength ratio 



284 



