TABLE S 



Schedule of Tests ~ Wave Size 





W 



jves 



k/L 



A/A 



Model 



Ship 



Length, ft 



Height, in. 



Length, ft 



Height, ft 



15 



3,4.5,6 



360 



6,9,12 



0.703 



60,40,30 



20 



4,6,8 



480 



8,12,16 



0.937 



60,40,30 



25 



5,7.5,10 



600 



10,15,20 



1.172 



60,40,30 



30 



6,9,12 



720 



12,18,24 



1.406 



60,40,30 



The radius of gyration was established experimentally at 25 percent LWL The natural 

 pitch period of the model for the load condition corresponding to 17,505 tons full scale was 

 1.44 seconds. The addition of Fin No. 1 increased the natural pitch period to 1.59 seconds. 

 It was not possible to obtain the natural heave period because of the limitations imposed by 

 the size of the model and the width of the test basin. 



TEST RESULTS 



The experimental results are presented in Figures 8 through 15. The results include 

 the experimental heave and pitch amplitudes and phase angles, the computed location of the 

 point of minimum vertical motion, the vertical motion and acceleration of any point along the 

 length of the ship, and the computed values of the bending moments experienced by Fin No. 1 

 in waves. All dimensional results are presented in full scale and are summarized in the con- 

 ventional dimensionless form. The pitch reduction effects of the various fin configurations 

 tested are also presented. 



Because of the frequent propeller emergence experienced during the tests with and 

 without fins, propeller rpm and surge data were erratic. The presentation of these data has, 

 therefore, been omitted. 



PITCH (Figure 8) 



Pitch amplitudes shown are experimental. Linearity of pitch amplitude with wave 

 height at constant speed and wave length was found to hold within the wave-height range of 

 the tests (the highest waves were 1/30 of their length). The data are presented in graphical 

 form, showing the amplitude of pitch per unit of wave height measured from trough to crest. 

 Pitch amplitudes for wave lengths not included in the direct presentation can be obtained by 

 interpolation. It will, however., be necessary to perform the interpolation graphically, as 

 linearity assumptions involving the wave length are not valid. 



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