Effect of Variation in Speed and Cable Length 



The basic design configuration of the cable-body 

 system having been determined, it is of interest to determine 

 the effects of changes in the speed and length of cable payed 

 out, using the results of Figure 4, and the tabulated func- 

 tions in (4) , calculations of these effects were made and 

 results presented in Figures 5, 6, 1 , and 8. Figure 5 shows 

 that, as the speed is reduced from 7.2 knots to zero, addi- 

 tional cable can be payed out to achieve a maximum depth 

 of about 17,000 feet without exceeding a static tension of 

 one-third the breaking strength of the cable. For the chosen 

 three-fourths-inch double-armor cable, this limiting tension 

 is approximately 15,000 pounds. Figures 6, 7, and 8 show 

 the effect of speed variation on the tension at the top, T^, 

 the depth, y, and the horizontal displacement of the body, 

 X, for fixed cable lengths of 1000, 3000, and 6000 feet. The 

 figure for maximum attainable depth shows a small discrepancy 

 between this computation and (1). This discrepancy derives 

 from the assumption made in (1) that the cable angle at the 

 bottom is 90 degrees. The curves in Figures 5, 6, 7, and 8, 

 based on the calculated values of cable angle shown in Figure 

 4, represent a refinement of the original design approximation, 



Further examination of Figures 6 and 7 shows that the 

 full speed capability has not been utilized since the tensions 



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