SIS 



to provide accurate ship's motion correc- 

 tions for underway gravity measurements 

 in midocean areas. 



Submersibles and helicopters liave unique 

 jidvantages over surface vessels for numy ap- 

 plications, but their operational costs must 

 be reduced and significant advances made in 

 positioning technology before they may be 

 used routinely for mapping and charting 

 surveys. 



The Commission recommends that the 

 National Oceanic and Atmospheric 

 Agency take the lead in accelerating de- 

 velopment of survey equipment for high 

 resolution measurement of bathymetric 

 and geophysical features. Funds should be 

 provided for present and projected Fed- 

 erally operated or funded ocean research 

 and survey vessels to equip them fully 

 with the most advanced sensor and data 

 processing systems relevant to their 

 missions. 



Navigation 



The past 30 years have brought enormous 

 improvements in the convenience and accu- 

 racy of marine navigation systems. The U.S. 

 Coast (ruiird has the major resiwnsibility to 

 provide and maintain navigational aids in 

 U.S. waters and to establish the rules of the 

 road. Its systems include LORAN A, 

 LORAN C, and a network of about 4-1,000 

 local visual, electronic, and audio aids. Addi- 

 tioiutlly, the Coast Guard issues permits for 

 and monitors some 23,000 private aids which 

 mark privately maintained channels, offshore 

 oil rigs, and piei-s. The Xavy has been the 

 major force in navigation systems develop- 

 ment, usually turning the systems over to the 

 Coast Guard for operation, and has pioneered 

 satellite navigation. Navy's TRANSIT sys- 

 tem now permits fixes to be obtained over 

 most of the earth's surface at no more than 



NASA satellites, like the Applica- 

 tions Technology Satellite from 

 )chich this vieic of the earth was 

 taken, may contribute to the 

 Nation's navigation services by 

 offering a means for the provision 

 of continuous positioning 

 information. 



90-minute intervals to an accuracy better than 

 ±0.2 nautical mile. TRANSIT is being made 

 available for general use, and the Navy is 

 stimulating development of low-cost receivers 

 and devices to interpolate between fixes. The 

 Navy also has developed OMEGA, a highly 

 accurate, very low-frequency, continuous 

 wave system, and is establishing it on an 

 operational basis. Thus, the Navy has devel- 

 oped systems adequate to most global naviga- 

 tional requirements, although precise sur- 

 veys will require other systems as well. 



The Commission has found, as did the Na- 

 tional Academy of Sciences Committee on 

 Oceanography and the President's Science 

 Advisory Committee before it, that the most 

 urgent needs for improved positioning sys- 

 tems are in the zone lying within 200 miles of 

 the I".S. coast but beyond the range of visual 

 navigation. A fully reliable, convenient, and 

 low-cost system which permits fixes within 



