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The MariPro Operation of Science Applications International Corporation is involved in the 

 design, manufacture and installation of a wide range of systems for military, scientific and 

 commercial customers. These systems are ocean based and consist of cables and various 

 sensors installed in water depths from deep abyssal ocean to shallow littoral. As examples, 

 they include a Training Range for the Navy, the acoustic source installation for the ATOC 

 program and the communications system from Pt Mugu to San Nicolas Island. 



The Fleet Tactical Training Range installed at San Clemente Island provides the Navy a 200 

 square nautical instrumented facility to provide the accurate three dimensional location of 

 underwater participants in Naval training exercises. This range consists of 8 cabled arrays 

 running from shore to sea. Each array has 8 hydrophones separated by one to two nautical 

 miles and a trunk to the beach landing. The program required the hydrophones to be placed 

 on the bottom with an absolute accuracy of better than 100 meters in water depths of up to 

 2000 meters. The planning for this system included a design compatible with the installation 

 requirements and an installation procedure to provide the required placement accuracy. 

 Historic data provided general bathyemetery and very limited ocean current data. This was 

 adequate to establish the general approach to the installation. However, bathyemetry over 

 each of the cable runs was acquired to establish the detailed cable deployment schedule. A 

 major problem in this type of installation is knowledge of ocean current profiles at the time 

 the cable is being deployed. This was accomplished by using a pair of doppler current 

 meters in real time. One was installed on the installation vessel and the towed near the 

 bottom. This approach worked, but limited the installation to speeds less than one knot 

 exposing the system to up to 60 hours of risk due to changes in the weather. Weather 

 forecasting played a critical role in the program. More detailed knowledge of the expected 

 ocean current in the area and its variability could have eliminated the need for real time 

 current measurements and allowed installation at higher speeds. This would have 

 significantly reduced the cost of the installation and reduced the risk of system damage or 

 loss due to changes in the weather. The availability of long term current data in the San 

 Clemente area could possibly be of benefit to the Environmental community. A 

 measurement program was undertaken by MMS in the Santa Barbara channel several years 

 ago to provide data on the transport of oil in the area in case of a major spill. This data base 

 was limited to the specific requirements of MMS. Whether or not there could have been an 

 overlapping program to include the Navy requirements is not known. However, there 

 appears to be a possibility that joint regional planning between agencies with vastly different 

 charters could have saved in the overall cost of both programs. 



The Acoustic Thermometry for Ocean Climate (ATOC) program will provide long term 



