In response to growing public concerns and recognition that further assessment of the system was needed, the Navy decided to initiate an environmental impact statement process. Because there is some potential for incidental harm to marine mammals, the Navy must obtain a Letter of Authorization from the National Marine Fisheries Service before SURTASS/LFA can be used. The decision on the authorization is expected later in 2002. As a result, a system such as SURTASS/LFA can provide the means to detect enemy submarines before they can get within the effective weapons range of U.S. ships. Demonstration of Capabilities

Results of SURTASS/LFA testing to date show that the system will increase the Navy’s capability to detect modern submarines at long range in deep, open ocean areas. The Navy planned for the evaluation to primarily focus on demonstrating the system’s capabilities in the open ocean. Other Antisubmarine Warfare Technologies Complement but Are Not Substitutes for SURTASS/LFA

Since the beginning of the program, the Navy has considered a number of existing and potential alternatives to SURTASS/LFA, and each time it found that the system provides long-range detection capabilities other systems could not provide.
What GAO Found

For decades, the Navy has been striving to improve its ability to detect potential enemy submarines before they can get within effective weapons range of U.S. forces. In 1985, the Navy established the Surveillance Towed Array Sensor System (SURTASS) Low Frequency Active (LFA) sonar program to develop a long-range capability for detecting a new generation of quieter Soviet nuclear and diesel submarines operating principally in the open ocean. However, as the Navy conducted testing of the system in the mid-1990s, some public interest groups and scientists raised concerns that SURTASS/LFA may cause harm to marine mammals. The Navy discontinued operational testing of the system and initiated an environmental impact statement process. The Navy will not begin testing or operating the system until it receives a Letter of Authorization from the National Marine Fisheries Service. A decision on the authorization is expected later in 2002. SURTASS/LFA will increase the Navy's capability to detect submarines in the open ocean, where the system was originally intended to operate. The Navy has considered a number of existing alternatives to SURTASS/LFA and found that the system provides long-range detection capabilities not available with other systems.