to the ri.shing rrounds and, once there, provide him v;lth InTormation 

 about tno bottom he I'ishes. 



The principal items of electronic equipment found on shrimp 

 vessels are automatic pilots, depth recorders, and radio telephones. 

 Tiio only navigational instrument, however, common to all craft vjith 

 the exception of motor boats, is the conpass. A fev vessels are equipped 

 vith radio direction finders, loran devices, and "Fischlupes". 



Automatic Pilot 



Automatic pilots vjere introduced in the shrimp fleet to 

 relieve tne crew from the chore of steering which, on lon^ runs, 

 presents a considerable fatigue problem. Since a course steered 

 electronically is more accurate than one steered by hand, both run- 

 nxng time and fuel consumption are reduced by the use of automatic 

 pilots. Unless equipped with remote control, however, the instrument's 

 use is confined to maintaining a heading. 



Some caution must be exercised in tho use of automatic pilots. 

 Errors in course may result from tixe circumstance that Lhe pilot ini- 

 tially was set on the basis of an inaccurate compass .ij Exclusive 

 reliance on the automatic pilot by crews who left the iiheel unattended 

 have been responsible for serious accidents at sea. Two serious stiort- 

 comings of tne instrument are its inaccuracy in rough seas and considerable 

 wear on the steering gear caused by bad vjeather. 



Depth Recorders 



Depth recording equipment is utilized for both navigating and 

 fishing. \Jhen used for navigatijig, depth of water and bottom contours 

 are determined to obtain vessel position. When used for fishing, good 

 bottom (smootn and muddy) is distinguished from bad bottom (rock or 

 coral) by the appearance of the graph made on the recording paper. An 

 instrument using a flashing light instead of a pan indicator is less 

 desirable since no permanent record is kept and tlie continuous watching 

 for the flashes imposes a strain upon the fisherman. 



When properly used, depth recorders are possibly the most 

 valuable instruments on board. A principal shortcoming of some of 

 the depth recording equipment installed on shi'imp vessels is the Inade- 

 quate protection from salt spray and moisture afforded to the working 

 parts. This deficiency increases the maintenance required. The mainten- 

 ance problem may be complicated further by the ignorance of vessel person- 

 nel in the care and use of the device. Moreover, it is reported that some 



11/ A five degree compass error in the heading from Tampa to Campeche 

 ijxjuld result in an error of about 60 miles if no corrective action is 

 taken. 



98 



