3. EQUIPMENT AND INSTRUMENTS 



43 



graphic survey ship requires the use of elec- 

 tric power and the generators must have a 

 capacity sufficient to supply power to all 

 equipments which may be in operation 

 simultaneously. 



A well-designed ship will provide spaces 

 for an oceanographic laboratory, a photo- 

 graphic laboratory, a sick bay, and work 

 shops for engineers, electronic technicians, 

 and carpenters. 



Smaller survey ships are small models of 

 the major ships and vary in size and mission. 

 Class II ships have accommodations for 8 

 officers and 50 men, and are able to work 

 in exposed areas, but for shorter periods of 

 time. Small auxiliary survey vessels are de- 

 signed for operations in harbors and shel- 

 tered areas close to a source of supplies. 

 Some are designed for specific duties such 

 as wire-drag surveys or current observations. 



3-2 Survey launches. — The ship's 

 launches, which also serve as lifeboats, will 



vary in size with the class of ship, and range 

 from 26 to 36 feet in length (Fig. 6). 

 Launches for hydrographic work generally 

 have a covered cockpit forward in which are 

 located a plotting table, echo sounder, and 

 electronic positioning equipment, if used. The 

 plotter, recorder, and echo-sounder operator 

 are stationed here. This cockpit should be 

 weather-proof and well lighted. The steering 

 station is located on a raised deck amidship. 

 Sextant angles are observed from this sta- 

 tion when visual control is used. The launch 

 is powered by a Diesel engine housed in a 

 covered cockpit aft. Engine controls are 

 usually mounted at the steering station. 

 Storage batteries for operation of echo sound- 

 ers and radiotelephone are charged by a 

 generator driven by the main engine. If 

 Shoran equipment is used, a separate power 

 supply is required, and is usually a small 

 Diesel-driven generator mounted in the en- 

 gine compartment. 



Figure 6. — Modern hydrographic survey launch. 



