RANGE INSTALLATION

The undersea warfare training range (USWTR) is a system of underwater acoustic transducer devices, called nodes, connected by cable to each other and to a landside facility where the collected range data are used to evaluate the performance of participants in shallow water training exercises. These transducer nodes are capable of transmitting and receiving acoustic signals from ships operating within the USWTR. The acoustic signals that are sent from the exercise participants to the range nodes allow the position of the participants to be determined and stored electronically for both real-time and future evaluation.

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Approximately 300 transducer nodes would be placed 1 to 3 nautical miles (NM) apart on the ocean floor over a 500-square-nautical-mile area, connected by commercial fiber optic undersea cable approximately 1.22 inches in diameter. The nodes, which are up to 48 inches high and 100 inches in diameter, would be designed to be consistent with local geographic conditions and to accommodate area activities such as fishing. The total bottom area covered by these components would be approximately 31,700 square feet.

At Site A, the interconnect cable between the nodes would not be buried. However, at Sites B and C, the interconnect cable between the nodes may be buried in the shallower depths due to potential entanglement concerns with bottom trawling fishing gear.

A trunk cable connecting the range to the shore facilities would be buried to a depth of approximately 3 feet. There would be two segments to the buried trunk cable. One segment would run from the shore to a junction box 25 NM offshore. Although the cable would be buried, the junction box would not. From this junction box a second buried cable segment would run to another junction box located at the edge of the range. Ocean-bottom burial equipment would be used to cut (hard bottom) or plow (soft sediment) a furrow approximately 4 inches wide in which the 2.3-inch cable would be placed. Cable installation would be accomplished using a tracked, remotely operated cable burial vehicle.

The trunk cable would be buried within the coastal zone and terminate in a cable termination facilility (CTF). The CTF would be a structure approximately 400 square feet in size that would house the power supplies, system electronics, and communications gear necessary to operate the offshore range. From there, information gathered on the USWTR would be routed to the Fleet Area Control and Surveillance Facility Virginia Capes (FACSFAC VACAPES).

Completion of the SWTR construction is scheduled to take place in three increments that would occur over a nine-year period (i.e., each phase would occur over three years). Construction of the instrumentation array is planned to be phased in, beginning with an initial increment of 200-square-nautical miles, followed by another 200-square-nautical miles, and a final increment of 100-square-nautical miles. Because of the size and operational requirements, the range initially (three to six years) would only be used in a limited manner.