Laying First Section Of Commonwealth Cable

Press, Volume C, Issue 29479, 4 April 1961, Page 15

Laying First Section Of Commonwealth Cable

(From the London Correspondent o) "The Press”)

LONDON, March 27. Her Majesty’s Telegraphic Ship Monarch is about to lay the first section of the telephone cable destined to reach practically all Commonwealth countries to carry telephone conversations, telegrams and telex messages. The Monarch is loading in the Thames before sailing for Scotland to pick up the shore end of the cable laid earlier this month at Oban. The first section of the Commonwealth cable, 2100 nautical miles long and known as CANTAT. is a single transatlantic telephone cable system carrying 60 circuits between Scotland and White Bay, Newfoundland. There will be a 450-mile extension to the mainland of Canada by a further submarine cable to the south bank of the Gulf of St. Lawrence. In the main crossing there will be 90 repeaters and seven submerged equalisers. The cable itself is a radical departure from previous types of deep sea cables used across the Atlantic in that (except for the shore ends of the cable which are in shallow water) it is unarmoured and very much lighter in weight. It was designed by British Post Office engineers, and it is being manufactured in the United Kingdom from raw materials from the Commonwealth. The strength of the cable lies in a high tensile steel strand situated at its centre within the inner cable conductor. This steel strand is narticularly resistant to kinking and twisting, an important factor when laying and repairing submarine cables. Though the comnaratively long and heavv. rigid reoeaters used by the Post Office «ive the highest possible reliabilitv. the laving of such unwieldy pieces of equipment pos“s a problem Submarine cable is laid from a cable ship over a series of pulleys while the ship steams steadily along

the route of the cable. The rigid repeaters will not go over the sheaves of the laying gear and arrangements have to be made for the repeater to bypass the laying gear by means of a steel rope which is attached to the cable on each side of the repeater. This bypass rope passes round the pulley of the gear while the repeater moves alongside in a trough which runs from the cable tanks to the stern of the ship. The laying operation can thus be continuous.

The main crossing of CANTAT will be laid by the Monarch between the end of March and the end of October.

The Monarch is the fourth cable ship of that name. Her commander is Captain O. R. Bates, who has been in the service of the Post Office for 21 years.