C. FACILITIES 



One of the critical needs of the Hydrographic Office in developing 

 and more effectively using geophysical instruments of all kinds is 

 improved calibration facilities and the development of standards and 

 procedures for calibrating, evaluating, and field checking all instru- 

 ments. Evaluation should include determination of the probable error 

 of measurements for each class of instruments through repeated 

 calibration runs, field tests, and application of sampling and other 

 statistical techniques. Two major facilities are badly needed: (1) a 

 towing tank for use in calibrating and evaluating the numerous current 

 meters used by the Office, and (2) a pressure-temperature calibration 

 facility of much greater capacity and flexibility. 



It is the recommendations of the Committee that steps be taken to 

 provide these facilities and other related facilities required in the test 

 and calibration of instruments as soon as possible. 



The need for a field facility located near the water has been discussed 

 widely within the Office. Several interim arrangements have been tried 

 or suggested for meeting requirements for field testing instruments. 

 The Committee recommends that a sustained effort be made to obtain 

 a small boat, docking facilities, and a small warehouse for field main- 

 tenance and storage. Such a facility should be within 100 miles of Wash- 

 ington and should be easily accessible by road. In addiion to Annapolis 

 and Patuxent, which have been considered previously, the possibility of 

 locating such a facility at the NRL Chesapeake Bay Annex should be 

 investigated. This has a small dock and limited shop facilities and is 

 less than 40 miles from the Hydrographic Office. It is recommended 

 that these and other possibilities be explored and that necessary steps 

 be taken to provide such a facility. 



D. GEOPHYSICAL DATA COLLECTION SYSTEM 



Appendix A of this report discusses systems concepts and concludes 

 that magnetic tape as a recording medium offers real advantage in 

 flexibility, an essential feature at this stage of development of a system 

 for oceanographic and other geophysical data collection. As is pointed 

 out in Appendix A, a system based on generation of FM signals at the 

 source offers advantages in that such signals are less subject to trans- 

 mission loss. They can be relayed acoustically or by a single conducting 

 cable using sea water as the return or, between surface points, by radio. 

 Conversion to digital form is simple, and such signals are less subject 

 to distortion with age than are analog voltages, if a control frequency 



1-4 



