ROUTE SELECTIOX AND CABLE LAYING 311 



The test room was greatly enlarged and fitted with the special gear 

 necessary for powering and measuring the system during laying. 



Loading Considerations 



When the ship is loaded, the cable is coiled carefully in the tanks, 

 layer upon layer — each layer being called a "flake". The coihng is 

 started from the outside of the tank and progresses clockwise toward 

 the center so that the armor is untwisted one revolution for each com- 

 plete turn in the tank. When paid out in the reverse order, this twist 

 is restored. 



Handling of the repeaters during loading presents a problem because 

 of the need to restrict their bending. After some experimental work 

 was carried out, splints were de^'ised to provide the needed rigidity. 

 These consisted of two angle irons each 12 ft long and equipped at the 

 ends with cold rolled steel rods ranging in length from 1| ft to 6 ft. By 

 this device it was possible to maintain rigidity over the main central 

 portion of the repeater, including the junction of the core tube with 

 the end nosing, and provide limited flexibility along the outer ends of 

 the core tubes which are less sensitive to bending. The splints were re- 

 moved once the repeater reached the tank. 



Repeaters are always stowed at the outside of the flake where they 

 need be subjected to only a minimum of bending. They are protected 

 with wood dunnage, which must be removed before the repeater is 

 paid out. 



With these modifications all repeaters and equalizers were laid 

 successfully from either forward or aft gear at a cable speed of around 

 three knots. 



Testing and Equalization 



Purpose — Once a submarine cable system has been installed, it is 

 accessible only at the ends for adjustment to improve performance, 

 save at great difficulty and large cost. As some irregularities cannot be 

 corrected from the ends, it behooves the designers to discover and ac- 

 count for such irregularities and to correct them before the cable is 

 finally on the ocean bed. 



The laying period offers the last opportunity for accomplishing this, 

 and indeed all too frequently, also the first. This fact, coupled with the 

 broadband design of the link and with the presence in the system of 

 active elements (the repeaters), necessitated a very comprehensive 

 program of tests and measurements during laying. 



