Cable layer explained

A cable layer or cable ship is a deep-sea vessel designed and used to lay underwater cables for telecommunications, for electric power transmission, military, or other purposes. Cable ships are distinguished by large cable sheaves[1] for guiding cable over bow or stern or both. Bow sheaves,[2] some very large, were characteristic of all cable ships in the past, but newer ships are tending toward having stern sheaves only, as seen in the photo of CS Cable Innovator at the Port of Astoria on this page. The names of cable ships are often preceded by "C.S." as in CS Long Lines.[3]

The first transatlantic telegraph cable was laid by cable layers in 1857–58. It briefly enabled telecommunication between Europe and North America before misuse resulted in failure of the line. In 1866 the successfully laid two transatlantic cables, securing future communication between the continents.

Modern cable ships

Cable ships have unique requirements related to having long idle periods in port between cable laying or repairs, operation at low speeds or stopped at sea during cable operations, long periods running astern (less frequent as stern layers are now common), high maneuverability, and a fair speed to reach operation areas.[4]

Modern cable ships differ greatly from their predecessors. There are two main types of cable ships: cable repair ships and cable-laying ships. Cable repair ships, like the Japanese Tsugaru Maru, tend to be smaller and more maneuverable; they are capable of laying cable, but their primary job is fixing or repairing broken sections of cable. A cable-laying ship, like Long Lines, is designed to lay new cables. Such ships are bigger than repair ships and less maneuverable; their cable storage drums are also larger and are set in parallel so one drum can feed into another, allowing them to lay cable much faster. These ships are also generally equipped with a linear cable engine (LCE) that helps them lay cable quickly. By locating the manufacturing plant near a harbor, cable can be loaded into the ship's hold as it is being manufactured.[5]

The newest design of cable layers, though, is a combination of cable-laying and repair ships. An example is the only U.S. naval cable layer-repair ship. Zeus uses two diesel-electric engines that produce 5000sigfig=2NaNsigfig=2 each and can carry her up to 15kn. She can lay about 1000miles of telecommunications cable to a depth of 9000feet. The purpose of Zeus was to be a cable ship that could do anything required of it, so the ship was built to be able to lay and retrieve cable from either the bow or the stern with ease. This design was similar to that of the first cable ship, Great Eastern. Zeus was built to be as maneuverable as possible so that it could fulfill both roles: as a cable layer or a cable repair ship.[6]

Equipment

To ensure that cable is laid and retrieved properly, specially designed equipment must be used. Different equipment is used on cable-laying ships depending on what their job requires. In order to retrieve damaged or mislaid cable, a grapple system is used to gather cable from the ocean floor. There are several types of grapples, each with certain advantages or disadvantages. These grapples are attached to the vessel via a grapple rope, originally a mix of steel and manila lines, but now made from synthetic materials. This ensures that the line is strong, yet can flex and strain under the weight of the grapple. The line is pulled up by reversing the Linear Cable Engine used to lay the cable.[7]

The most common laying engine in use is the Linear Cable Engine (LCE). The LCE is used to feed the cable down to the ocean floor, but this device can also be reversed and used to bring back up cable needing repair. These engines can feed 800feet of cable a minute. Ships are limited to a speed of 8kn while laying cable to ensure the cable lies on the sea floor properly and to compensate for any small adjustments in course that might affect the cables' position, which must be carefully mapped so that they can be found again if they need to be repaired. Linear Cable Engines are also equipped with a brake system that allows the flow of cable to be controlled or stopped if a problem arises. A common system used is a fleeting drum, a mechanical drum fitted with eoduldes (raised surfaces on the drum face) that help slow and guide the cable into the LCE.[7] Cable ships also use “plows” that are suspended under the vessel. These plows use jets of high-pressure water to bury cable 3feet under the sea floor, which prevents fishing vessels from snagging cables as thrall their nets.[8]

HMTS Monarch[9] (renamed CS Sentinel 13 October 1970)[1] completed the first transatlantic telephone cable, TAT-1, in 1956[10] from Scotland to Nova Scotia for Britain's General Post Office (GPO).

The Ocean Marine System Group used a cable laying software designed by Makai Ocean Engineering Inc., in five of their cable installation and repair vessels. The MakaiLay software has been used by 90% of the worlds' global fleet of cable ships. These five OMS vessels were installed with this software on August 23, 2023, to reduce failures during installation and increase reliability, safety, speed, and accuracy:[11]

Repeaters

When coaxial cables were introduced as submarine cables, a new issue with cable-laying was encountered. These cables had periodic repeaters inline with the cable and powered through it. Repeaters overcame significant transmission problems on submarine cables. The difficulty with laying repeaters is that there is a bulge where they are spliced in to the cable and this causes problems passing through the sheave. British ships, such as HMTS Monarch and HMTS Alert solved the problem by providing a trough for the repeater to bypass the sheave. A rope connected in parallel to the repeater went through the sheave which pulled the cable back in to the sheave after the repeater had passed. It was normally necessary for the ship to slow down while the repeater was being laid.[12] American ships, for a time, tried using flexible repeaters which passed through the sheave. However, by the 1960s they were also using rigid repeaters similar to the British system.[13]

Another issue with coaxial repeaters is that they are much heavier than the cable. To ensure that they sink at the same rate as the cable (which can take some time to reach the bottom) and keep the cable straight, the repeaters are fitted with parachutes.[13] [12]

List of cable ships

Royal Navy

US Navy

See also

External links

Notes and References

  1. Web site: History of the Atlantic Cable & Submarine Telegraphy - HMTS Monarch (4). atlantic-cable.com. 24 March 2019.
  2. Web site: NavSource Photo, USS Neptune (ARC 2) bow sheaves. navsource.org. 24 March 2019.
  3. Web site: History of the Atlantic Cable & Submarine Telegraphy - Leo Parrish and CS Long Lines. atlantic-cable.com. 24 March 2019.
  4. Gill . A. J. . January 1947 . H.M.T.S. Monarch . The Post Office Electrical Engineers' Journal . 39 . January 1947 . 129–138 . London . The Institution of Post Office Electrical Engineers . 29 January 2020.
  5. https://www.nytimes.com/interactive/2019/03/10/technology/internet-cables-oceans.html How the Internet Travels Across Oceans, by Adam Satariano, graphics By Karl Russell, Troy Griggs and Blacki Migliozzi, photographs by Chang W. Lee, New York Times, March 10, 2019
  6. Sanderlin, T., Stuart, W., & Jamieson, D.R., (1979). Cable Laying Ship. Presented at the April 18, 1979, meeting of Chesapeake Section of The Society of Naval Architects and marine Engineers.
  7. Thomas N. Sanderlin, Stuart M. Williams & Robert D. Jamison.(1979).Cable Laying Ship.Presented at the April 18, 1979, meeting of Chesapeake Section of The Society of Naval Architects and marine Engineers.
  8. Frank, D. Messia; Jon, B. Machin; Jeffery, A.Hill. (2000). The Economic Advantages of Jet-Assisted Plowing.Source: Oceans Conference Record (IEEE), v 1, p 649-656, 2001; ; DOI: 10.1109/OCEANS.2001.968800; Conference: Oceans 2001 MTS/IEEE - An Ocean Odyssey, November 5, 2001 - November 8, 2001; Sponsor: Marine Technology Society; IEEE; OES; Publisher: Institute of Electrical and Electronics Engineers Inc.
  9. Web site: hmts-alert.org.uk - Registered at Namecheap.com. www.hmts-alert.org.uk. 24 March 2019. https://web.archive.org/web/20170118164200/http://www.hmts-alert.org.uk/. 18 January 2017. dead.
  10. Web site: History of the Atlantic Cable & Submarine Telegraphy - Cable Signalling Speed. atlantic-cable.com. 24 March 2019.
  11. Web site: Kugeler . Hermann . OMS Group Commissions Makai Software Across Their Installation and Repair Fleet . subtelforum.com . 24 August 2023 . Submarine telecoms Forum . 7 December 2023.
  12. K. R. Haigh, Cableships and Submarine Cables, pp. 211–214, Adlard Coles, 1968 .
  13. https://books.google.com/books?id=d_XOKdeyXrYC&pg=PA716 "Two new British cable ships completed"
  14. Web site: Swinhoe . Dan . A brief history of cable ships . www.datacenterdynamics.com . datacenterdynamics . 1 December 2023.
  15. Web site: History of the Atlantic Cable & Submarine Telegraphy - CS Hooper/Silvertown . 22 January 2020 . Glover . Bill . 22 December 2019.
  16. April 7, 1873 . Launch of a Telegraph Steamer . The London and China Telegraph . 15 . 501 . 229 . Lonfon . 22 January 2020.
  17. Web site: History of the Atlantic Cable & Submarine Telegraphy - CS H. C. Oersted . 27 January 2020 . Glover . Bill . 4 March 2017.
  18. Web site: Glover . Bill . The Evolution of Cable & Wireless, Part 3 . Atlantic-cable.com . 21 February 2019.
  19. News: Ship Seine . 21 February 2019 . The Illustrated London News . 1 November 1873 . The ship Seine laying the land end of the Brazilian submarine telegraph cable at Madeira, illustration from the magazine The Illustrated London News, volume LXIII, November 1, 1873. . 27 July 2020 . https://web.archive.org/web/20200727060910/https://www.gettyimages.co.uk/detail/illustration/ship-seine-laying-land-end-of-brazilian-submarine-stock-graphic/677102407 . dead .
  20. Web site: Glover . Bill . History of the Atlantic Cable & Submarine Telegraphy - CS Gomos . 25 January 2020.
  21. 1874. Telegraphic Progress in 1874 . Engineering . 19 . January 1875 . 12–13 . London .
  22. Huurdeman, Anton A., The Worldwide History of Telecommunications, Wiley, 2003 .
  23. Web site: Glover . Bill . History of the Atlantic Cable & Submarine Telegraphy - CS La Plata . 25 January 2020.
  24. Web site: Glover . Bill . CS Burnside . atlantic-cable.com . Atlantic cable . 1 December 2023.
  25. Web site: Glover . Bill . CS Cable Queen . atlantic-cable.com . History of the Atlantic Cable & Undersea Communications . 1 December 2023.
  26. Web site: Glover . Bill . CS Cable Queen . atlantic-cable.com . History of the Atlantic Cable & Undersea Communications . 1 December 2023.
  27. Web site: Mauric . Damien . Secret Scuba Spot: Charlie Brown Wreck in Statia . www.scubadiving.com . Padi . 1 December 2023.
  28. Web site: C.S. LONG LINES - IMO 5421235 . www.shipspotting.com . Ship Spotting . 1 December 2023.
  29. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  30. Web site: TYCO PROVIDER - IMO 7616779 . www.shipspotting.com . Ship Spotting . 2 December 2023.
  31. Web site: TYCO INTERNATIONAL LTD BERMUDA 10K . faculty.babson.edu . Tyco International . 2 December 2023 . 216.
  32. Seafarers Bring Newest AT&T Cable Ship to States . Seafarers Log . January 1993 . 55 . 1 . 3 .
  33. Seafarers Sail Through a Year Of Military Operations, Legislation, New Vessels and Elections . Seafarers Log . January 1993 . 55 . 1 . 14 .
  34. Fifth AT&T Ship Joins Cable Fleet . Seafarers Log . January 1993 . 55 . 1 . 3 .
  35. Web site: Glover . Bill . CS Cable Innovator . atlantic-cable.com . Atlantic Cable . 1 December 2023.
  36. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  37. Web site: Sharda . Tyco Resolute: The Mightiest Cable Laying Ship at the Sea . marinesite.com . 18 August 2019 . Marine Insight . 2 December 2023.
  38. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  39. Web site: Brock . Joe . Inside the subsea cable firm secretly helping America take on China . www,reuters.com . Marine Insight . 2 December 2023.
  40. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  41. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  42. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  43. Web site: A global guide to the latest known locations of the world's cableships*, as at May 2004 . diselduck.info . 2 December 2023.
  44. Web site: Attack Cargo Ship AKA-49 Vanadis. www.navsource.org. 24 March 2019.