conventional designs, by the minimum bending diameter of the 

 cable. The length of the drums, however, need only be enough 

 to accommodate the number of wraps required to absorb the 

 tension in friction. Figure 11 shows a typical design using 

 this principle. 



The difficulty in using the twin-drum system (or any 

 other drum system for that matter) , lies in the necessity of 

 passing the instrument modules under tension over the drums. 

 The modules may be expected to be of large diameter in 

 comparison with the cable, and of a length not significantly 

 smaller than the drum radius. As a result, the concentrated 

 loading on the module and the sharp bend in the cable at the 

 connector may exceed strength limitations. The magnitude of 

 this problem cannot, of course, be properly assessed until 

 specifications are developed for a particular system. 

 Nevertheless, it is likely that a drum system will not be 

 acceptable for many such applications unless the drums are 

 made considerably larger than would normally be required. 

 For the system proposed here, tests with a small model twin- 

 drum system are in progress, but results were not available 

 in time to be included in this report. 



Although the basic idea of a tractor-type capstan system 

 has long been used in handling metal tubing and cable during 

 the manufacturing process, the idea has only recently been 

 applied to shipboard cable-handling problems. The principal 



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