by adding modular weights to the anchor after its implant and that the 

 alignment of the modules could be controlled by properly designed guide- 

 line and bottom guide posts. 



Scope of the Study 



The scope of this work covers two ocean experim.ents: the first was 

 a series of parametric tests of a system to a depth of 600 feet, and the 

 second was a series of validation tests to a depth of 4,500 feet. Attempts 

 at mating two structures of basic shapes were included at both depths. 

 The quantitative analysis of the guideline performance data as well as a 

 qualitative evaluation of the design, deployment, and operation of the 

 guideline components are documented. A discussion of the experimental 

 results is given in this document along with recommendations on the 

 design and operation of guideline systems. 



BACKGROUND 



A flexible guideline system is simple and inexpensive; yet effective 

 as a means of restricting the lateral motions of a payload throughout its 

 vertical travel in the water column. The components of the system are 

 readily available as off-the-shelf items. However, the most serious 

 drawback to the system is believed to be its apparent low reliability, 

 caused mainly by line entanglement. 



Guidelines have been used in shallow-water undersea oil-well drilling 

 by offshore oil industries as the most efficient, proven technique for 

 vertical guidance [1]. The main application of the guideline system is 

 for subsea well-head completions. Large well-head equipment, such as 

 blow-out preventers, have been lowered and assembled under the sea, using 

 guidelines for restricting lateral and rotational motion and guide posts 

 for seafloor alignment. In addition, more advanced, manned, completion 

 concepts, such as Lockheed's new well-head completion chamber [2] and 

 Deep Oil Technology's maintenance submersible [3], utilize the concept of 

 multiple guidelines. Although such hardware systems are being developed 

 and tested in shallow-water depths, documentation of guideline design 

 and operation is not available in the open literature. 



The Navy needs to use guideline systems in much deeper water than 

 does industry. As a start in developing this capability, guideline 

 systems have been adopted in two major Navy experiments, both of which 

 have been conducted at relatively shallow depths (600 feet) . During the 

 SEALAB III [4] and SEACON I [5] emplacements, guideline systems using 

 two guidelines were employed. These systems were designed with little 

 engineering data and minimum analysis. However, the generally satisfactory 

 performance of these systems encouraged further improvement in hardware 

 design and stimulated more rigorous examination of the entanglement prob- 

 lem encountered at deep depths. 



