aa 
The various systems currently available or in the devel- 
opment stage have been investigated and evaluated from the 
viewpoint of Ocean Surveys. For use within 200 miles of 
land, several commercial systems are available which meet 
the above criteria, and various of these are already in use 
by the Coast and Geodetic Survey, the Coast Guard, and the 
Navy. It is not within the limits of this plan to recommend 
one over the other, merely to prescribe that any system used 
meet the requirements outlined above. 
No present system meets all the requirements for the 
long-range coverage. Loran-C meets most of them, but the 
coverage is limited. In those areas where the system is 
operational, it is adequate for Ocean Surveys. The radio 
sextant will provide ocean-wide coverage, but it is expen- 
sive, entails complex equipment, and provides positional 
accuracy of only about s 2 nautical miles. Probably the 
navigational satellite system offers the best practical 
solution to the navigational problem. It will, when fully 
operational, provide ocean-wide coverage within the accuracy 
limits desired, will be within a reasonable price range for 
the shipboard equipment, and will meet satisfactorily the 
other requirements listed above. The Navy and the Coast and 
Geodetic Survey have already made plans to obtain early 
models of the required shipboard equipment for evaluation 
when the system is operational. Only the OMEGA system, cur- 
rently in the research and development stage, competes with 
