Havelock has given an example showing how to correct resistance data obtained from 

 friction body experiments for the wave resistance. 3 In the discussion of this paper, Weinbium 

 has pointed out that these estimates may be much too low for moderate Froude numbers since 

 they are based on a parabolic waterline while the actual form can be much fuller (see page 

 269, Reference 3) . 



The results of the computations are presented in various ways . Figure 2, reproduced 

 from Reference 4, shows the comparison of the calculated wave resistance coefficient 

 B 



-^Su'< 



with the "residual resistance" coefficient C . Schoenherr's fr'ictional 



resistance line was used to evaluate C 



The coefficients reach their maximum at moderate Froude numbers which is character- 

 istic of very full forms. Figure 3 shows the calculated wave resistance coefficients 



R 



plotted against y o = for three depth-length ratios. 



8p g B'H' 



n L 



Figure 4 shows the wave resistance coefficients of a parabolic form (for which p = 0) 

 with the same proportions as the friction body. It can be seen that for this form, the coeffi- 

 cient of resistance is much lower than that of the fuller form except in the region of the large 

 hump. 



0.5 0.4 



0.25 0.225 



Figure 3 - Wave Resistance Coefficients r Plotted Against Speed 

 for Three Different Drafts 



