88 NOTES ON THE PERFORMANCE OF THE S. S. TYLER. 



cent, which is the figure for minimum residuary resistance, the easing of the bilge 

 being so sHght that the vessel has this amount of parallel body for all intents and 

 purposes. 



In the 1912 paper a claim was made for a 3 per cent saving, due to the forward 

 lines; the trials at the Delaware Breakwater amply justify this claim. Recent 

 average practice would require at least 2,000 indicated horse-power for 12% knots; 

 1,750 indicated horse- power, as realized, therefore represents a 12^ per cent sav- 

 ing, all of which, however, is not claimed for the bow lines. It would not be diffi- 

 cult to cite similar cases requiring 2,100 indicated horse-power for this speed. 



It is to be regretted that there is no other ship in the Old Dominion fleet that 

 can be compared directly with the Tyler. The Madison is a larger vessel, passenger 

 carrying, and 4 knots faster. These ships compare approximately as follows : — 



Madison Tyler 



Length ....': 359 ft. o in. 331 ft. o in. 



Breadth 42 ft. o in. 47 ft. o in. 



Draught 16 ft. 6 in. 16 ft. 6 in. 



Displacement 4.500 4,750 



Sea speed (knots) 16 12 



I. H. P 4,000 1,500 



Both vessels have a single screw. These figures are included more to show the 

 difficulty of comparison than as an actual comparison. From effective horse-power 

 curves from a previous vessel it is, however, possible to arrive at a fair comparison. 

 The type vessel is similar to the S. S. Madison in general form. 



Item Type Tyler 



Length 350 ft. o in. 331 ft. o in. 



Breadth 42 ft. o in. 47 ft. o in. 



Draught 17 ft. 10 in. 16 ft. 11 in. 



Displacement 4,875 4,875 



Block coefficient .65 .65 



Speed in knots 13 13 



E. H. P 1,100 1,200 



Ratio, beam to draught 2.36 2.78 



Speed-length ratio .695 .715 



The Tyler is shorter and wider than the type ship and only requries 100 more 

 horse-power for the same speed at the same displacement. Both these perform- 

 ances are creditable to the designers, but especially so in the case of the shorter 

 and wider vessel. The Tyler is an example of a case where several cooks did not 

 spoil the broth. 



