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temperature measurements of the Pacific Ocean to establish the trend of global temperature. 

 An acoustic source was installed on a sea mount off the coast of Northern California at Pillar 

 Point. The installation required a detailed knowledge of the bathymetry from the beach to 

 the installation point. Since the projector was to be installed on the sea mount, the 

 requirements for accurate navigation and depth measurements were stringent. The site was 

 surveyed using a precision depth recorder and differential GPS navigation. As in the San 

 Clemente installation, accurate predictions of weather and sea conditions over periods of 

 several days was required. The penalty for poor depth data, navigation or weather prediction 

 is the loss of expensive and difficult to replace equipment. 



Communications between the mainland and San Nicolas Island play a vital role in the 

 development and test of Naval Systems. The microwave system in use prior to the 

 installation of the fiber optic cables provided limited and marginal communications. The 

 FCXTUS program replaced microwaves with a 1.2 Gb/s optical system with significantly more 

 capacity and reliability. The installation required sea to shore interfaces at both Pt Mugu and 

 San Nicolas Island. These interfaces were constructed using reconditioned drill pipe as a 

 conduit for the cable. The design of this protection required estimates of sand transport, 

 depletion during winter and replacement in summer. Some data was available, but 

 coordinated data bases from the many programs studying this area would have made the 

 design process more satisfactory from an engineering standpoint and would have reduced the 

 risk of system damage during its 25 year service life. The cable route from the mainland to 

 the island was planned using standard bathymetric charts. These gave a general indication of 

 depths and slopes. Prior to the cable deployment, a detailed survey was accomplished using 

 a precision depth recorder and differential GPS as a navigation aid. This data, along with 

 data collected by the Navy provided the data base for the program. This data was not 

 coordinated with NOAA or any other agency. Whether or not this would be a useful thing is 

 not known. However, large amounts of data are collected for many programs. If this could 

 be coordinated, it might reduce the need for other collection programs. 



All of the described programs use ships of opportunity for the at-sea work. Since dedicated 

 vessels require operation and maintenance cost beyond the scope of current programs, SAIC 

 has developed a containerized installation system. The elements of this system include the 

 cable hold back machine and its power pack, cable splicing and navigation vans. These units 

 use standard ISO containers or container form factors allowing them to be shipped as 

 standard ocean freight. In most markets a wide range of ships are available for charter at 

 day rates. These are normally off-shore oil supply boats with large un-obstructed after 

 decks. The containers are designed for rapid mobilization. This permits the conversion of a 



