The vessel Léon Thévenin does an amazing job. Currently docked in Cape Town, South Africa, the ship is the main reason undersea fibre optic cables such as Seacom, EASSY and others keep operating – well, partly.
At 107.8 m in length and 17.8 m in breadth, the Orange-operated Léon Thévenin is an undersea fibre cable repair vessel, and currently holds the world record of repairs in the Atlantic Ocean agreement (ACMA) with 230 repairs over 29 years.
The ship has a wide arsenal of equipment for tracking faults, locating cables, and repairing them – and one very special robot. “The cable ship is equipped with traditional cable work tools – grapnels, buoys, ropes, dead-weight but also with a modern device, the ROV. This remotely operated vehicle is used for different operations on the fiber optic cables: detection, cutting, recovery, jointing and testing. The Thévenin is capable of operating repairs in very shallow waters, as well as in deep waters – between 10 and 7 000 meters,” Orange explains.
The ROV, affectionately named Hector 5, is the undersea vehicle used for locating the cable, cutting it, and bringing it to the surface so that highly-trained professionals can make repairs. “Hectors are powerful and full customized work-class ROVs dedicated for cable works. The Hector ROVs are specialized in burial by jetting after the laying of repaired cables. They can also operate surveys. Their HD video cameras allow finding cables down to 2,000 m depth.”
Telecommunications operator Orange, recently took selected media on a tour of the vessel, and pointed out how the ship operates.
“Cable ship Thévenin is able to operate in extreme conditions. With her high freeboard, she may sail in deep seas with poor weather conditions. The bows – located 8 meters above sea level – allow working in sea state 6, with waves up to 6 meters.”
Journalists were taken from the Mission Room, to the bridge, the Espadon test room, the installation room, transmission room, and the jointing room – where cables are joined together.
With a full load speed of 15 knots, she needs to always be ready for when damage occurs to an undersea cable around the African coast, and from 2001 to 2012 she spent 40% of her time at sea, the rest on alert 24 hours a day.
Charlie Fripp – Consumer Tech editor