96 EFFECTIVENESS OF THE COMMITTEE ON OCEANOGRAPHY 



There are two main propulsion generator sets driving two motors geared to a 

 single shaft. All propulsion machinery is housed in one compartment. There is 

 a raised focsle deck extending off about one-fourth of the length; the main deck- 

 house extends off about two-thirds of the length. The towing machinery is in the 

 after part of the deckhouse and the aft one-third of the length is open deck over a 

 large salvage hold with restricted 'tween deck height. Steering is manual, by 

 means of cable. The pilot house is small, amounting to hardly more than a steer- 

 ing station; there is a small chartroom and a radioroom on the foscle deck. Offi- 

 cers quarters and crew mess facilities are on the main deck; crew quarters are on 

 the second deck. The ship has difficulty in making headway against head seas 

 and yaws considerably in normal weather. Because of the deep draft, steering is 

 good at low speed. General operating characteristics are good. Reasonably 

 adequate accommodations for 5 officers and 30 crew members can be provided by 

 rearrangement of main and second deck compartments and by extension of the 

 superstructure deck and main deckhouse. Heating and ventilation and evapo- 

 rator capacity are inadequate. Generator capacity is inadequate. The shell 

 plating and house sides require insulation in way of accommodations for habit- 

 ability. 



(b) It is concluded that ships of this class can be converted to hydrographic 

 surveying ships of restricted utility though at considerable cost. The capabilities 

 of the converted craft would approximate those required for class III surveying ship 

 but operating efficiency would be limited by the excessive draft (15-foot) which 

 cannot be changed. The operational area would be restricted to certain areas of 

 southeast Alaska and even there the deep draft would be a handicap to successful 

 operation. In addition to this restriction on operations, the efficiency of the 

 converted ship would be approximately 80 percent of that of a ship designed and 

 constructed specifically for hydrographic surveying. The minimum cost of 

 conversion is estimated at $1,072,000. Detailed estimates of conversion costs are 

 contained in appendix B. 



(c) Major features of the conversion required are as follows: 



(1) Extend focsle deck and shell plating above main deck aft approximately 

 8 feet. 



(2) Extend main deckhouse aft approximately 20 feet to provide space 

 for shops and additional crew quarters. 



(3) Extend deckhouse on superstructure deck aft approximately 8 feet to 

 provide office and plotting room space. 



(4) Extend bridge deck and pilothouse aft approximately 8 feet to provide 

 enlarged bridge area and space for chartroom. Restep foremast on flying 

 bridge deck to eliminate obstruction in working space on bridge deck. 



(5) Install davits on main deck to handle two launches, 24 to 26 feet in 

 length. 



(6) Revise crew accommodations to provide quarters and adequate 

 sanitary facilities for a crew of 30 men. 



(7) Rearrange officers quarters to provide accommodations for five officers. 



(8) Revise heating, ventilation, lighting, and sanitary facilities to suit the 

 new arrangement. 



(9) Insulate shell plating and exterior sides of deckhouse in way of accom- 

 modations. 



(10) Renew main propulsion generators, ships service generators, heating 

 boiler, supply and exhaust fans, evaporator, and auxiliary machinery. 



(11) Provide complete outfit and equipment. 



4. AFT class 



(a) TJ.S.S. Seneca, ATF 91, was examined at Naval Operating Base, Norfolk, 

 Va., on February 14, 1958, by Capt. W. N. Chovan and Comdr. F. j. Bryant- 

 Ships of this class are fleet ocean tugs with single screw diesel electric propulsion. 

 There are four main propulsion generator sets in one compartment driving four 

 motors in a separate compartment. The four motors drive the single shaft 

 through a common reduction gear. The ship is flush deck with considerable 

 sheer; bulwarks extend the full length of the main deck. The towing machinery 

 in installed on the main deck aft of the deckhouse. There is a tripod mast aft 

 with a 10-ton boom. Operation characteristics except steering are good. Steer- 

 ing is by means of an electrohydraulic steering engine; the poor steering qualities 

 are the result of the hull form rather than defects in the steering system. Sta- 

 bility is good and decks are reasonably dry in rough weather. For operation of 

 the main propulsion machinery the control station is in the motor room but an 

 engineer watch must also be maintained in the generator room. This requires a 

 minimum of four engine room personnel per watch. Officer's quarters are in the 



