to be 10,000 pounds. The spring-mass system was assumed to be excited by a sinusoidal 

 ship heave described by the equation: 



Ship heave motion = Y sin 1 



Where Y is the maximum heave amphtude of the ship in feet and T is the period of the mo- 

 tion in seconds. Four amphtude-period combinations were assumed as follows: 



AMPLITUDE (Y) PERIOD (T) 



5 seconds 

 10 seconds 

 15 seconds 

 20 seconds 



The rope used was specified as 4y2-inch circumference Plimoor nylon. Figure D-1 shows a 

 plot of maximum line tension versus line length for the conditions described above. 



Case II 



Maximum line tensions were computed using a MIZAR heave period predicted by 

 Kreitner's approximation (DTMB Report 1235, Sept. 1958) and heave amplitudes supplied 

 by NAVSEC Code 6136 for MIZAR. All other parameters were assumed to be the same as 

 given in Case I. Figure D-2 is a plot of maximum line tension versus line length for the con- 

 ditions of Case II. 



Case III 



The spring-mass system was analyzed using 4V2-inch circumference Plimoor nylon rope, 

 8-inch circumference Plimoor nylon rope, 4!/2-inch circumference Samson 2-in-l nylon rope, 

 and 8-inch Samson 2-in-l nylon rope. For these cases, the rope was assumed to be deployed 

 from the U-frame located at Station 40 on MIZAR. Consequently, roll and pitch motion 

 were included as additional exciting motions. Amplitudes and periods used were provided 

 by NAVSEC Code 6136 as described in Case II. Static weight of ALVIN in water was as- 

 sumed to be 9,000 pounds and 12,000 pounds (i.e., 0% and 33% loss in buoyancy due to 

 syntactic foam saturation). Figures D-3 and D-4 are plots of maximum line tension versus 

 line length for the various conditions described above. 



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