STABILITY OF LIFEBOATS. 

 By Professor H. A. Everett, Member. 



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



New York, December 11 and 12, 1913.] 



The following presents the results of an investigation undertaken the past 

 summer to determine the stability of several types of lifeboats in common use on 

 ocean-going ships of these parts. The boats were all stock boats, new, and ready 

 for immediate service. 



In its essence, the work consisted of the customary calculations for the curves 

 of statical stability after having made inclining experiments upon each boat to de- 

 termine the location of the center of gravity. There were four boats and each was 

 inclined in two conditions : ( i ) light with but the apparatus and the two observers 

 on board, and (2) loaded, with the number of persons which the Rules and Regula- 

 tions of the United States Board of Supervising Inspectors permit. The work pro- 

 vided theses for two members of the graduating class of the Massachusetts Insti- 

 tute of Technology, A. H. Pitz and C. S. Hsin, and was under the immediate 

 supervision of the author. 



Four boats were used ; the principal dimensions are given in the following table, 

 and the lines are given on Plates 73 and 74. 



Principal Dimensions. 



♦Including experimental apparatus and 2 men. fBefore and after launching. 



Numbers i and 2 were of the standard type of open boat provided with tanks 

 as shown on the lines and were of practically the same external form. Construc- 

 tion plans of these are shown on Plates 75 and 76. Both conform to the U. S. rules 

 with air-tank capacities of 51.8 and 76.4 for the wood and metallic boats, 

 respectively. 



