THE RESISTANCE OF A HEAVY FLEXIBLE CABLE FOR TOWING 

 A SURFACE FLOAT BEHIND A SHIP 



Introduction 



In an attempt to predict the behavior of a float towed behind a ship by a 

 long, heavy, flexible cable, two distinct problems arose, for whose solution a 

 knowledge of the forces in the cable was required. 



1. What must be the strength of the cable? To answer this, it was necessary 

 to know the tension in the cable at the ship. 



2. How does the cable affect the behavior of the float? For it is clear 

 that the cable has a two— fold influence upon the float. The horizontal component 

 of the cable tension at the float balances the resistance of the fluid to the motion 

 of the float. In addition to this, there is the vertical component of the tension 

 which in effect increases the displacement of the float and consequently affects its 

 resistance and behavior. To answer this second question it is necessary, then to 

 know the horizontal and vertical components of the tension, or, what is the same 

 thing, to know the tension at the float and the angle that the cable makes with the 

 horizontal at that point. 



FIG. 1. 



Previous work on the form and resistance of a towing cable has furnished no 



1 ? 



solution of the present problem. Mathematical expressions and numerical solutions 



(1) A.R.McLeod. On the action of wind on flexible cables, with applications to 

 cables towed below aeroplanes and balloon cables. R. and M. 554. Oct. 1918. 



(2) H.Glauert. The form of a heavy flexible cable used for towing a heavy body 

 below an aeroplane. R. and M. 1592. Feb. 1934. 



