The chosen design meets the stated requirements for 

 minimum cost and minimum difficulty of installation. Installation 

 was accomplished by first implanting the outer moorings and join- 

 ing them to form the "inverted V". The Signal Cable/Sensor Array 

 was then attached and paid out from a barge on the sea surface 

 toward shore. The inner mooring was next attached and lowered 

 from another barge while the first barge hauled the signal cable in- 

 shore, pulling down the entire array. 



Tables 3-1 and 3-2 provide summaries of calculated stresses and 

 deflections at critical locations for various assumed currents. These 

 data were derived from a digital computer program, SEASNAKE, 

 which is described in detail along with a more complete tabulation 

 of analjrtical results in Reference 6. 



The following sections briefly describe each portion of the telescope 

 structure. Further details may be obtained by reference to the 

 engineering drawings. 



3.1.1 Signal Cable /Sensor Array 



The array is made up of four shots of armored electrical cable 

 interconnected and terminated by metal junctions which serve to 

 transmit loads and contain the sensors. Referring to Figure 3-1, 

 we see that the shore end is terminated in a splice box which connects 

 the system to a heavy PI 15 cable carrying the signals to shore. 

 The first shot is 11,200 feet long and is laid slack on the bottom down 

 to Station 1. At Station 1 (see photo in Figure 3-4) the signal cable 

 is held by a bridle to the Inner Mooring Assembly which anchors the 

 shore end of the taut array. The Inner Mooring Assembly also pre- 

 vents rotation of the cable at Station 1 and holds it about 80 feet off 

 the bottom to avoid topographical hazards. See Figure 3-2 and des- 

 cription of the Inner Mooring Assembly below. Six hundred feet of 

 signal cable on the shore side of Station 1 is wrapped with polyurethane 

 tape to provide extra abrasion protection where the cable makes the 

 transition from the bottom to the floating Station 1. Some 90 floats 

 are also attached to this section of cable near Station 1 to hold the 

 cable clear of the mooring. Station 1 is articulated to permit relative 

 pitching motion between the cables on either side of the Station. This 

 feature prevents bending of the cable at the terminations and is espec- 

 ially important during deployment and retrieval. 



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