294 ELECTRIC PROPULSION OF MERCHANT SHIPS. 



stroy a ship. There are a lot of small details that should be gone into. However, I see no 

 reason why the electric drive should not have its place just as well as the reciprocating en- 

 gine or any other type of prime mover, if the question of costs is studied for the particular 

 vessel and trade route and proper attention is given to the details of construction. 



Mr. a. p. Alli;n, Member: — I have listened with great interest to Mr. Emmet's pa- 

 per, especially so as coming from one who has had probably more to do with the develop- 

 ment of the electric drive than any one man or group of men in this country, if not in the 

 world. But generally I think that we have not given due consideration to the practical side 

 of our propelling units during the last few years as to its adaptation to the work it has to 

 perform as a marine propelling unit. 



While I am not an enthusiast on the subject of electric propulsion of merchant ships 

 at the present time, I do believe that it is quite necessary to encourage the development of this 

 type of equipment to the extent of installing the same on a few of our present cargo vessels. 



The successful development of the electric drive will depend to a great extent upon 

 just how much the designers and manufacturers of this equipment are willing to be guided 

 ^by the experience and be advised by the practical shipbuilders and operators, so that we 

 may not have the many lamentable failures and unpleasant experiences that we are now 

 having with the reduction gear drive, and which might have mostly been avoided if the 

 gear manufacturers had worked in closer cooperation with the ship engineers in this coun- 

 try during the past three years. 



To illustrate this situation, I would state that in 1916 I was connected with a shipbuild- 

 ing organization that built the first American cargo vessels to have reduction gear turbines, 

 the order for these turbines and gears being placed with Mr. Emmet's organization. Many 

 additional duplicate orders followed during 1917 and 1918. After a number of these ves- 

 sels had been placed in service, experiencing frequent gear troubles, we became fully con- 

 vinced that while these troubles might be partially due to faulty foundations, poor align- 

 ment or faulty lubrication, etc., the main cause was due to insufficient tooth area. 



While the satisfactory operation of the turbine and gear was guaranteed by the manu- 

 facturers, we naturally felt quite vitally interested in the successful operation of these ves- 

 sels, and I took particular occasion in 1917, at a conference held with the engineers of the 

 manufacturers supplying these gears, to urge on them that it would be absolutely necessary' 

 to increase the gear areas at least 100 per cent; that the fault with the gears was that they 

 had been designed only to care for the turbine load and was merely duplicating stationary 

 plant conditions where the gears were subjected to a constant known load only. My argu- 

 ment at this conference was that the load brought on the gears from the propeller in bad 

 weather would be from 100 to 200 per cent greater than any load the turbine would give 

 and that it would be necessary to redesign their gears accordingly. 



My arguments were of no avail, and to make a bad story worse they insisted that the 

 overload nozzles, which permitted about 20 per cent overload, be removed as one of the 

 principal causes of the extreme gear wear, thus reducing the overload capacity to about 5 

 per cent. Think, gentlemen, of a marine propelling unit with a 5 per cent overload capacity. 



Mr. Emmet's later investigations, results of which are shown on Plate 120, corroborates 

 the position that we took at that time, but his investigations came too late to save the 

 shipping interest of the country from losses that are and will run into millions of dollars 

 from delays and replacements. 



