THE APPLICABILITY OF ELECTRICAL PROPULSION TO BATTLE- 

 SHIPS, TOGETHER WITH THE EXPERIENCE GAINED WITH IT 

 ON THE JUPITER. 



By Lieutenant S. M. Robinson, U. S. N., Member. 



[Read at the twenty-second general meeting of the Society of Naval Architects and Miarine Engineers, held in 



New York, December 10 and 11, 1914.] 



There are at present so many different methods of ship propulsion that it is 

 impossible to make any general statement as to which method is the best. Ques- 

 tions of horse-power, speed, size of vessel, duty it has to perform, etc., all have 

 so much bearing on the subject that each class of vessel has to be considered sepa- 

 rately. For this reason this paper has been limited to a discussion of battleship 

 propulsion. 



A great number of schemes for the propulsion of battleships have been tried 

 and a still greater number have been proposed, but it is not believed that any of 

 them have such ideal qualities for this purpose as electric propulsion. 



Before taking up the applicability of electric propulsion to battleships, a de- 

 scription will be given of the probable arrangement that would be used. Briefly, 

 it would consist of two high-speed turbo-generators and four induction motors. 

 The motors would be arranged with one motor on each of four shafts. There 

 would be a switchboard (or rather a board for mounting instruments) in each 

 engine-room, but under all ordinary conditions of steaming, all operating would be 

 done from one switchboard and only one turbo-generator would be used. Only 

 at very high speeds would both generators be used, and in that case the two en- 

 gine-rooms would be operated independently. The switchboards would be so ar- 

 ranged that either generator could run all four motors from either switchboard; 

 also so that any motor could be cut out at any time, allowing the ship to be run 

 with three motors. All these switches would be of the simple knife-blade type, en- 

 closed in waterproof boxes so arranged that they could not be moved when the cir- 

 cuits were alive. For connecting each pair of motors for ahead or astern motion, 

 oil switches would be used which would be capable of breaking the heaviest cur- 

 rent which could pass. In actual operation, however, the field circuit of the gen- 

 erator would always be open before moving these switches, so that the oil switch 

 would really break very little current. 



No attempt will be made to give a detailed description of the turbines, gen- 

 erators, and switches that would be used for a battleship, as the number of pos- 

 sible arrangements is too great. However, the equipment would be similar in most 

 essentials to that in use on the Jupiter, and that will be described later on when 

 that installation is taken up. The principal difference between the two equipments 



