Estimated percent reduction in collisions, rammings, 



and groundings (C/R/G) by different vessel traffic 



systems (VTS) levels. 



' Definition of VTS levels. L-O, Mandatory vessel bridge to bridge radiotelephone (passive); L-1, 

 (B-B) + Traffic separation scheme (TSS) (passive): L-2. (B-B) + TSS + Vessel Movement Reporting 

 System (VMRS) (advisory); L-3, (B-B) + TSS + VMRS | basic surveillance (active); L-4, (B-B) + 

 TSS + VMRS + advanced surveillance (active); L-5, (B-B) + TSS + VMRS + automated advanced 

 surveillance system (active). 



^ Definition of accident types. 1, Collision between two or more moving vessels (crossing, meeting, 

 and overtaking); 2, collision involving a moving vessel and a vessel(s) at anchor, moored, docking, 

 or undocking; 3, rammings of fixed objects, such as bridges and piers; 4, rammings of nonfixed 

 objects, such as buoys or floating or submerged objects; and 5, groundings with or without damage to 

 the vessel. 



' Present distribution of C/R/G by type is 19 percent for type 1, 16 percent for type 2, 24 percent 

 for type 3, 14 percent for type 4, and 27 percent for type 5. 



Increases in ship sizes and speeds and the resultant reduction in 

 their maneuverability make it necessary to improve the ability of 

 these ships to navigate in confined waters during periods of reduced 

 visibility. USCG is continuing its studies to determine the 

 requirements for various maneuvering devices in light of the 

 increased size of ships. It is also developing procedures and 

 equipment for tank vessel inspections, analysis of new marine 

 construction materials, and collision analysis to lessen casualties at 

 sea. 



Despite all precautions, there will always be a need for search and 

 rescue. USCG, which responds an average of 140 times each day to 

 emergency afloat situations, supports R&D to improve the speed and 

 efficiency of rescue craft, illumination from helicopters for night 

 searching, and the rapidity of personnel recovery systems. Better 

 identification and location systems for use in search and rescue 

 missions are also being explored. To facilitate communications, a 

 vital part of search and rescue, USCG is developing L-band (100- 

 4000 MHz] communications equipment for its ships and aircraft, 

 obtaining necessary data for the development of a maritime satellite 



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