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CHAPTER 4. EQUIPMENT AND INSTRUMENTS 

 41. SURVEY SHIPS AND AUXILIARY VESSELS 



The modern survey ships of the Coast and Geodetic Survey are steam or motor 

 vessels approximately 200 feet in length, with facilities to accommodate a complement 

 of 10 to 20 officers and 60 to 70 crew. This personnel is sufficient to operate three or 

 four launch hydrographic parties, two or three topographic or triangulation parties, 

 and be engaged in ship hydrography simultaneously. The storage space is sufficient 

 to carry a 6 months' supply of materials and equipment for survey operations, and pro- 

 visions consisting of frozen vegetables and meat, canned goods, and other food staples. 

 The fuel and water capacity enables the ship to remain for periods of 3 to 4 weeks on 

 a working ground distant from port. 



The survey ships of the Coast and Geodetic Survey are listed in table 8 with 

 dimensions and particulars tabulated with appropriate notes. 



Each ship is designed and equipped to enable the survey party aboard to operate as 

 a complete and independent unit for combined operations and in offshore and remote 

 areas. On the working ground the ship is used to survey the greater part of the off- 

 shore hy(irography, in addition to serving as living accommodations for topographic, 

 triangulation, and launch hydrographic subparties which work independently from the 

 ship during the daytime. Equipment is carried for the establishment of one or more 

 shore parties, which are often supplied at regular intervals. Many other operations, 

 through which data for the compilation of nautical charts are obtained, are performed 

 by the personnel on board the vessel. 



Auxiliary vessels of the Coast and Geodetic Survey are designed to operate inde- 

 pendently or in conjunction with a survey ship. The larger vessels have sufficient fuel 

 and hold capacities to remain on the working ground for periods of at least 2 weeks and, 

 in general, are small models of the larger survey ships. Some of the smaller auxiliary 

 vessels are equipped for wire-drag surveys in addition to the more usual hydrographic 

 surveys. Auxiliary vessels are generally used for surveying in protected waters and, 

 if operated independently, not far from a shore base or headquarters. 



The dimensions and particulars of the auxiliary vessels of the Coast and Geodetic 

 Survey, in 1942, are contained in table 9. They range from 52 to 98 feet in length and 

 generally contain living accommodations for sufficient personnel to operate them for 

 hydrographic surveys and an additional supplemental unit engaged in topography, 

 triangulation, or small-boat hydrography. 



411. General Description of a Survey Ship 



A well-designed survey ship has suitable quarters for officers and crew, ample 

 storage space for supplies, and efficient apparatus for carrying, lowering, and hoisting 

 survey launches and small boats. A well-lighted and fully equipped drafting room and a 

 large well-equipped pilothouse are essential in hydrographic surveying, and there should 

 be suitable spaces for the installation of sounding and position-finding apparatus. The 

 propelling machinery and deck machinery are subjected to hard usage and should be of 

 sturdy construction. 



