inch to 1-1/2 inch, the in-water weight has increased from 0.5 lbs per 

 foot to 0.6 lbs per foot, and the handling, support, and storage problems 

 have been compounded by the substantial increase in length. This in- 

 crease In diameter is important not only because of the support,handling 

 and storage problems, but also because of drag considerations during 

 operations. During a typical operation the support vessel must move the 

 entire length of cable through the water; as the cable becomes larger and 

 heavier the drag problem grows exponentially. This is due not only to the 

 increase in cross-sectional area of the cable but also to the increased 

 diameter of support members. 



Since the CURV IV cable will be three to four times as long as the 

 CURV in cable, the problem grows even more acute and the size and 

 weight must be kept to absolute minimums. 



Based on past CURV experience^ it is assumed that the size and weight 

 of this cable required for CURV transmissions and the interfaces in sup- 

 port^handling and storage will establish a technical barrier. A more de- 

 tailed discussion of each aspect, the problem and the expected results is 

 given below. 



TRANSMISSION CONSIDERATION 



As was pointed out earlier there are several aspects to the cable 

 transmission problem, namely Power Transmission, TV Transmission, 

 and Control Signal Transmission. 



Power Transmission 



The first problem is the transmission of approximately 30 KVA of 

 power to the vehicle. It is desirable to separate the main power from the 

 instrumentation power; therefore, approximately 27 KVA needs to be trans- 

 mitted separately from the 3 KVA instrumentation power. In order to 

 transmit the 27 KVA of main power and the 3 KVA of instrumentation 

 power, it is necessary to utilize several large conductors. A preliminary 

 study on optimizing power utilization for CURV IV indicated that if a trans- 

 mission voltage of 1 300 V were used to minimize line loss and provide ade- 

 quate regulation, and a central vehicle power source were developed to take 

 advantage of all available power, it would take nine #9 wires to transmit 

 the 30 KVA. 



159 



