Mo^o^i^5 jfunD 



ADVISORY COMMITTEE ON THE LANGLEY 

 AERODYNAMICAL LABORATORY 



HYDROMECHANIC EXPERIMENTS WITH FLYING BOAT 



HULLS 



By H. C. RICHARDSON, Naval Constructor, U. S. Navy 



chairman of sub-committee on hydromechanics in relation to aeronautics 



(With Six Plates) 



During- the latter half of 191 3 the following work of interest was 

 carried on at the Model Basin at the Washington Navy Yard. 



This work comprised an investigation of the forms of hulls, of 

 flying boats in order to determine (i) their resistance at " displace- 

 ments corresponding to speeds," on the water, and (2) their resist- 

 ances " submerged," as a means of approximating their total head 

 resistances in air and of determining an approximate " coefficient of 

 fineness of form." 



As a result a form of hull has been derived which appears to 

 have decided advantages over those already in use in the Navy, so 

 far as resistance on the surface and in the air is concerned. Such 

 a hull slightly modified to overcome structural difficulties is now 

 being tried on a new navy machine. 



Plates I, 2, and 3 contain plots of the results of the experiments, 

 while plates 4, 5 and 6, illustrate the models used. 



PLATE 1 



This plate contains plots of model runs for the following models, 

 1591-3. 1592-1, i592-5> i593-i> 1602-1, and 1617-1. 



At the foot of the sheet are plots of net resistance, and of 

 derived e. h. p. for the full size computed on the assumption that 

 the total resistance of the full size model at the corresponding speed 

 is proportional to the displacement. As the models were all 1/9 full 

 size the corresponding speeds for the full size are V9 = 3 times those 

 for the models, and the resistances 9^ = 729 times those of the models. 



Smithsonian Miscellaneous Collections, Vol. 62, No. 2 



I 



