PART I. DISCUSSION 



INTRODUCTION 



The sound speed tables presented in H. O. Pub. No. 614 , after 

 Kuwahara^, present sound speed as a function of temperature, salinity, 

 pressure, and latitude. His tables were developed from mathematiceil 

 analysis of specific volumes rather than empirical sound speed meas- 

 urements. Actual measurements of sound speed in sea water indicate 

 Kuwahara's speeds are approximately 4 meters per second too slow. 



With the development of progressively nnore complex weapons 

 systems it became necessary to have more accurate sound speed 

 information. As a result of this recognized need, a conference^ of 

 interested parties was held at the Hydrographic Office in May 1961 

 for the purpose of resolving whether or not a new equation for the 

 calculation of sound speed should be adopted. It was generally agreed 

 that Wilson's equation'^ (shown below) should be adopted for Naval 

 applications. This decision was reached with the knowledge that 

 research presently being conducted may yield equations which are 

 somewhat more accurate. 



Vm/sec. = 1449.14 + Vp + V^ + V, + V. 



stp 



Where: 



Vp 



1.60272 X 10-1 P +1.0268 x 10"^ P^ +3.5216 x lO-^ p3 

 -3.3603 X 10-12 p4 



Vs = 1.39799(5-35) +1.69202 x lO^^ (S-35)^ 



\ = 4.5721T -4.4532 X 10"^ T^ -2.6045 X 10"'* T^ +7.9851 x 10'^ t" 



Vstp 



(S - 35) (- 1.1244 X 10-2 J .^7 7711 ^ ^Q"^ T^ +7.7016 X 10"^ P 

 -1.2943 X 10"^ P^ +3.1580 x IQ-^ PT+ 1.5790 x 10"^ PT^) 

 + P(- 1.8607 X 10"'* T +7.4812 X 10"^ T^ +4.5283 x 10"^ T^) 

 + P^(-2.5294 X 10"^ T +1.8563 x 10"'^ T^) +P^-1.9646 X 



10-'° T). 



