these forces would slacken the cable to a dangerous extent than 

 over-stress it. We therefore imposed a safe "G" limit at the 

 stern chute of the cable-laying barge. The 200 foot chain leader 

 is included to clear the wire rope from topographical hazards. 



The upper ends of the mooring cables are floated to support the 

 cable and chain leader and provide excess buoyancy to pre-stress 

 the entire array. The 228 floats on 18 inch centers provide 1300 

 lbs. of sub-surface buoyancy to hold the mooring system taut and 

 vertical after initial implantment. They are closely spaced to 

 minimize the depth of the deepest floats in the final telescope con- 

 figuration. The remaining floats are appropriately spaced over 

 the available cable length up to the Head Frame. Small floats were 

 used primarily because they were the only economical deep sea 

 floats available. They also smooth tension gradients and provide 

 damping of cable oscillations. After the moorings are joined at 

 the Head Frame, the "inverted V" remains about 30 feet below the 

 sea surface, thus minimizing the risk of damage due to shipping 

 or storms while awaiting attachment to the Signal Cable /Sensor 

 Array. 



In the original design, 840 lbs. of buoyancy for each mooring was 

 uniformly distributed above the cluster of 228 floats. All the stress 

 and deflection data tabulated in this paper have been calculated from 

 this original design. We subsequently learned that, because of cold 

 flow or creep, a significant fraction of the floats in the cluster of 

 228 may fail during the first year's service. To compensate for 

 this, an additional 650 lbs. of buoyancy was added to the upper 820 

 ft. of each outer mooring. The effect of this additional buoyancy is to 

 increase the initial nominal stress levels by about 20%, to increase 

 the stability, and to increase the stress levels at the extreme 1. 5 

 knot current condition by only 2%. Float performance is discussed 

 further in Sections 3.1.9 and 4. 1.4. 



3.1.4 Signal Cable (Vector Cable Co. Dwg. A-5051) 



The signal cable is a double-armored, eight conductor neoprene 

 cable of a design which has been used in many oceanographic appli- 

 cations. The center conductor is #16 AWG stranded copper wire. 

 The remaining seven conductors are #20 AWG stranded copper wire. 

 Insulation is a . 021" wall propylene copolymer. These conductors 

 are wrapped with fiberglass yarn and imbedded in neoprene of . 062" 

 minimum wall thickness to form the watertight electrical cable. The 



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