DISCUSSION 



This study was conducted to provide a design for a cable- 

 towed system capable of making simultaneous measurements at 

 a great many depths in a vertical profile down to 5000 feet, 

 with continuous monitoring of the instrumentation o The 

 result is a generalized design (shown diagrammatically in 

 Figure 13) , satisfying the basic requirements of such a system. 



The most promising means for achieving such depths at 

 reasonable towing speeds is the use of double-armor cable 

 with clip-type fairing. The fairing must be limited to 

 relatively short lengths, probably no greater than one or 

 two hundred feet, and the upper end of each fairing length 

 must be tied back into the cable by means of a swivel support. 

 The required downforce on the bottom end of the cable may 

 be obtained by a combination of weight, and hydrodynamic 

 force produced by depressing wings. To facilitate handling, 

 the body weight should not exceed 1000 pounds. 



A depth of 5000 feet can be attained with only 6200 feet 

 of cable at a towing speed of 7 knots, using three-quarter- 

 inch-diameter double-armor faired cable, without exceeding 

 one-third the breaking strength (approximately 15,000 pounds). 



The "Caterpuller" offers the most promise in shipboard 

 handling of systems containing rigid instrument modules dis- 

 tributed along the faired cable, A twin load-drum should be 

 satisfactory for systems not containing such modules. 



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