Page 319 equipment and instruments 4121 



The principal specifications of the Explorer are as follows: 



Length overall 220 feet, 8 inches. 



Length between perpendiculars 198 feet, 8 inches. 



Breadth, molded 38 feet. 



Depth, molded, to upper deck , 23 feet. ' 



Draft, molded, mean load -- 15 feet. 



Displacement, loaded 1,850 tons. 



Shaft horsepower 2,000. 



Speed at 130 r. p. m 15 knots. 



Cruising radius 8,000 miles. 



Water 175 tons. 



FueloiL 320 tons. 



Diesel oil 13 tons. 



Gasoline --- - 5 tons. 



4121. General Description 



The ship is of all-steel construction, with a raked stem and cruiser stern, complete main and upper 

 decks, a lower deck forward and abaft the machinery space, and a long superstructure deck. Double- 

 bottom tanks, extending from the forepeak aft to frame 75, are subdivided for fuel oil and water. 

 The forward tanks extend u^d to the lower deck, and the double-bottom tanks below the machinery- 

 spaces extend up the sides to the lower-deck level for bilge protection. Between frames 75 and 85 is 

 a dry tank under the lower deck, aft of which is the afterpeak. 



The hull is subdivided by eight watertight bulkheads so arranged that the vessel is a two-compart- 

 ment ship. Bulkhead plating and stiffeners are welded throughout. There are only three openings in 

 the bulkheads below the upper-deck level and these may be closed by watertight doors of the sliding 

 type, electrically controlled from the pilothouse, and in case of failure they may be closed from the 

 upper deck by emergency hand-operated controls. 



The shell seams are riveted and the butts flush- welded. The deck plating is riveted to the beams; 

 the seams and butts are welded. The decks have no sheer and only the upper and superstructure 

 decks are cambered. Calked wooden decking is laid over the weather decks, fastened with galvanized 

 iron deck bolts, cut to length, and welded to the deck. Through bolts are not used. The shell plating 

 and decks are supported by a system of transverse framing, spaced 27 inches apart, and by transverse 

 web frames and longitudinal girders. 



The propelling machinery consists of a steam turbine operating a single propeller through a 

 double-reduction gear in a single case. Steam is provided by two watertube boilers, with a working 

 pressure of 350 pounds per square inch with 200° Fahrenheit superheat at the superheater outlet. 

 The engines and boilers are in separate compartments amidships. 



The electric plant consists of: two turbine-driven main generators, each of 50-kw capacity, 120-volt 

 direct current, two-wire, compound-wound, arranged for parallel operation; a 25-kw d-c motor genera- 

 tor, directly connected to a 40-hp a-c three-phase, 220/440-volt motor installed for the purpose of 

 converting shore alternating current to 120-volt direct current for ship use during lay-up periods; a 

 10-kw d-c Diesel generator for emergency use; and two 5-kva 60-cycle turbo-generators used in con- 

 nection with the operation of echo-sounding apparatus, synchronized clocks, and other survey 

 equipment. 



The evaporating and distilling plant has a rated capacity of 2,000 gallons of fresh water for 24 

 hours. 



Accommodations are provided for 23 officers and 68 men. The living quarters are adequate, prop- 

 erly lighted, heated, drained, ventilated, equipped, located, and arranged, all in accordance with existing 

 rules of the United States Bureau of Marine Inspection and Navigation for new construction. The 

 decks in the accommodation spaces are covered throughout with an approved latex-type deck cover- 

 ing or ceramic tile. The furniture in general is of steel construction built to Navy Department 

 specifications. 



A well-appointed hospital space suitably fitted with berths, toilet facilities, medicine lockers. 

 X-ray machine, etc., is located at the main deck level. 



A mechanical ventilating-and-blower system provides 10 changes of air per hour in accommoda- 

 tion spaces and 15 changes per hour in toilet, galley, and hospital spaces. The ventilation of living 

 quarters is provided by four supply and four exhaust fans and the machinery spaces are ventilated 

 by two supply and one exhaust fan. Designated spaces are heated by tempered outside air. 



