5. HYDROGRAPHY 



165 



which are important to a complete record of 

 the operation, shall be entered at the be- 

 ginning of each day's work. 



When the hydrography is controlled by 

 sextant angles, the names of the personnel 

 engaged in the surveying, and the number 

 of the instrument used by each, shall be en- 

 tered in the appropriate spaces of Stamp No. 

 32 — Personnel (Fig. 56). The correctness of 

 the instruments used shall be verified and 

 that fact noted after the number of each 

 instrument. 



If the hydrography is controlled by an 

 electronic system of positioning. Stamp No. 

 32A shall be used, and entries made in all 

 appropriate spaces (Fig. 57). 



When operations are on a watch basis and 

 most of the personnel are relieved at regular 

 intervals. Stamp No. 32 or 32A should be used 

 to record the changes. For temporary relief, 

 when only one person is relieved, or when 

 two members of the group change places, the 

 fact shall be recorded in the remarks 

 column. 



5-91 Identification of electronic equip- 

 ment. — A change of a part or unit in an 

 electronic system used to control a survey 

 may alter the calibration of the system. Any 

 change made at a ship or shore station must 

 be reported and recorded at the time the 

 change is made. 



It is desirable to have a history of the 

 performance of various types of equipment, 

 and it may be useful at times to have a 

 history of a specific ship or shore station 

 set. See Chapter 3. 



Stamps No. 45, 50, and 104 (Fig. 58) shall 

 be used to identify EPI, Raydist, or Shoran 

 ship and ground stations used to control the 

 survey. This information shall be entered at 

 the beginning of each day's work, and any 

 changes which occur during the day shall be 

 noted in the remarks column. 



5-92 Sounding apparatus. — The kind and 

 instrument number of the sounding appara- 

 tus used shall be entered in rubber Stamp 

 No. 33 (Fig. 59) at the beginning of the day. 

 On ships which use shoal and deep water 

 echo sounders at various times during the 



day, each instrument must be identified and 

 the source of the soundings must be shown 

 in the remarks column when changing from 

 one to the other. If a PDR is used, this fact 

 should be noted immediately below the stamp. 

 When leadline or pole soundings are re- 

 corded, the number of the leadline shall be 

 entered below the stamp or in the remarks 

 column and a reference shall be made to 

 the volume and page where the leadline com- 

 parison is recorded. 



5-93 Comparison of sounding apparatus. 



— Any comparison of a leadline, or the lines 

 on a bar check apparatus, made with a 

 standard shall be recorded in the columns 

 below Stamp No. 35 (Fig. 60). This stamp 

 shall also be used to record echo sounder 

 calibrations obtained by the bar check meth- 

 od at any time during the day's work. 



Comparisons between simultaneous verti- 

 cal cast and echo soundings shall be recorded 

 under the headings of Stamp No. 43 (Fig. 

 61). The registering sheave or leadline num- 

 ber should be noted and reference made to 

 the correction factor for the sheave or the 

 comparison of the leadline with the standard. 



Phase comparisons observed with 808 or 



BAR CHECK 

 LEADL IN C CO M P*H I 0O» 



Vollmeler 



Sea ■S/r/OO-t-h 



_ Frequency Meier ^O C^S^ 



Bar Check Results 

 Leadline No 

 Latitude 



fGood^ 



^/ --?/. 7 



Fair Poor 



Longitude 7/ - 3^ . O 



Figure 60. — Record of bar check with entries prop- 

 erly made. 



No 43 SIMULTANEOUS COMPARISON 



Vertical Cast True Depth Echo Sounding 



Figure 61. — Stamp used for recording simultaneous 

 comparisons. 



