2. The motions of the pay load in the water column were stable, and the 

 position of the guide frame was dependent solely on static forces. The 

 dynamic motions of the payload were negligible under the prevailing 

 current of 0.4 to 1.0 knot. 



3. The basic design of the hardware for the single and double guideline 

 systems was generally adequate. 



4. The mating of two anchor blocks on the seafloor was not successful 

 during the sea tests. The handling hardware needs improvement. 



5. The basic recommendation for guideline system design and operation: 

 do not allow the accumulation of torque or the relaxation of tension in 

 the cable system at any time. 



CONCLUSIONS AND RECOMMENDATIONS 



Design of the Guideline System 



Guideline. The tension, type, size, and rotational qualities of the 

 rope are extremely important in designing or selecting the guideline to be 

 used in the system to ensure entanglement-free operation. 



1. Tension. Guideline tension should be as high as possible 

 to maintain positive control of the payload motion. In most cases, the 

 recommended guideline tension would be the lift line tension divided by 

 twice the number of guidelines. Double guidelines would require only 

 one-half of the tension required by the single guideline. The lower 

 limit of the guideline tension could be as low as 10% of the lift line 

 tension and still provide satisfactory restriction to payload motions 

 with minimum surface wave and current excitations. 



2. Type. Synthetic ropes are recommended for all short-term, 

 low-tension guidelines; steel wire ropes are recommended for long-term, 

 shallow-water guidelines; and Kevlar 29 rope, even though it was not 

 field-tested, is recommended for deep-depth guidelines. Each type of 

 rope has characteristics that have influenced these recommendations. 

 Synthetic rope, jacketed steel wire rope, and three-strand wire rope 

 exhibit poor abrasion resistance (the abrasion resistance of Kevlar 29 

 rope is still unknown) . Improvement of the guide cone design could lower 

 the abrasion-resistance requirements of the guideline. Steel wire ropes 

 are too heavy for deep depths; synthetic rope and Kevlar 29 rope are both 

 lightweight, but the latter' s high-strength characteristics recommend it, 

 in addition. Six-strand wire ropes have better abrasion resistance than 

 three-strand ropes, but the rotational properties of the six-strand ropes 

 are not as good as the 3x19, torque-balanced ropes. 



3. Size. The size of the guideline depends on the required 

 guideline tension and the weight of the anchor, which, in turn, depends 

 on the tension requirement. If lightweight anchors are to be used, such 



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