Subsea Cable Repair: From the Great Eastern to ABB Ships

About 200 submarine cable faults are reported worldwide each year, and cables on the ocean floor carry 95 percent of global telecommunications data. Subsea cable repair is still the work of a small fleet of specialist ships that drag grapnels, launch remotely operated vehicles and splice in new cable in a jointing cabin on board. This post starts with the Great Eastern's hunt for a lost Atlantic cable in 1866 and ends with the 2026 shortage of repair ships, set against cable cuts in the Baltic and the Red Sea, including where ABB's ship systems and robot arms fit.

Orange Marine's cable ship Raymond Croze moored in Toulon, 2016. Photo: Nicolas Corbel / Wikimedia Commons (CC BY-SA 4.0)

How the Great Eastern fished a lost cable out of the Atlantic

The first transatlantic telegraph cable, laid in 1858, failed within weeks. For the next attempt, in 1865, the cable went aboard the SS Great Eastern, built by John Scott Russell and Isambard Kingdom Brunel and fitted with three iron tanks that held 2,300 nautical miles of cable. On 2 August 1865, after 1,062 nautical miles had been paid out, the cable snapped near the stern and the end was lost. The ship came back in 1866 with a new cable, started paying it out on 13 July and reached Heart's Content in Newfoundland on 27 July. The unfinished 1865 cable still lay on the seabed, about 2.5 miles down.

The Great Eastern at Heart's Content, Newfoundland, in July 1866, the month the new Atlantic cable landed. Photo: attributed to Robert Edward Holloway, via Wikimedia Commons (public domain)

In August 1866 the fleet went back to fish for it, using positions recorded mainly by Captain Moriarty of the Royal Navy. Robert Halpin, the Great Eastern's first officer, guided the grappling ship Albany to the spot, and on 10 August its five-pronged grappling hook on a stout rope caught the cable. That night the cable slipped from its buoy, and it slipped again several more times. In early September it finally came up, and getting it safely aboard the Great Eastern took 26 hours. It was spliced to new cable and landed at Heart's Content on 7 September, which gave the Atlantic two working lines.

Crew on the deck of the US cable ship Dellwood as its grapnel picks up a cable, Seattle, 10 May 1924. Photo: Unknown / Wikimedia Commons (public domain)

The routine of finding the fault electrically, grappling, buoying the ends and splicing on deck has changed little since. Halifax in Nova Scotia was home to about half a dozen repair ships for most of the 20th century, among them the CS Minia and CS Mackay-Bennett, and their crews developed tools such as the plough. Grapnels came in rigid types for sand and flexible ones for rock, and in deep water a cutting grapnel brought up one end at a time. The robots came later, from the navy and the oil fields: the US Navy funded cable-controlled recovery vehicles in the 1960s, and ROVs became essential in the 1980s, once offshore work went deeper than divers could reach.

A chain grapnel of the kind dragged over the seabed to recover a cable, on display. Photo: Gaius Cornelius / Wikimedia Commons (CC BY-SA 4.0)

Why cable repair ran short of ships in 2026

In Britain, repair capacity has become a political issue. On 22 October The Telegraph reported that the country has one British-flagged ship dedicated to repairing telecoms cables, Global Marine's CS Sovereign, built in 1991, based in Portland, Dorset, and due to leave service by 2030. Officials looked at a replacement but balked at a cost estimated at more than £300m. Six repair vessels serve the maintenance agreements in the Atlantic and Northern Europe, first come, first served. The same day a government white paper proposed powers to direct repair companies during security incidents and prison terms of up to 14 years for intentional damage.

CS Sovereign, the only British-flagged ship dedicated to telecoms cable repair, moored in Wilhelmshaven in 2012. Photo: Ein Dahmer / Wikimedia Commons (CC BY-SA 4.0)

Most faults come from ordinary shipping. Geoff Huston, writing on CircleID on 14 October, counts about 200 faults a year and puts some 86 percent down to fishing or anchoring. The Baltic has seen 11 disruptions to its cables and pipelines since 2023, and in September 2025 several cables cut in the Bab el-Mandeb Strait disrupted about a quarter of capacity between Asia, Europe and the Middle East. A repair still starts with a grapnel. The ship hooks the cable, cuts it, buoys one end and recovers the other, then splices in a new section in its jointing cabin, where the fibre is fusion spliced, tested and sealed. Each repair costs roughly half a million to a million dollars.

A technician prepares a fibre optic splice with a fusion splicer in Vorarlberg, Austria, 2019. Photo: Asurnipal / Wikimedia Commons (CC BY-SA 4.0)

Robots already do the seabed part. Global Marine's Atlas ROV has 300 kW of installed power, works down to 2,000 metres and carries two Schilling Orion seven-function manipulators plus a cable cutter and gripper. It has been used on repair projects, including a 1 km stretch of the FLAG cable, and the company's XT600 trencher buries cable up to 3 metres deep. ABB's part so far is the ship itself. In March ABB won a contract from Colombo Dockyard for the power, propulsion and automation of two hybrid-electric cable repair ships for Orange Marine, due in 2028 and 2029, with Azipod DO units for precise manoeuvring and ABB Ability 800xA automation.

The cable ship Peter Faber launches its ROV during work on the TAT-14 cable system, April 2005. Photo: tom jervis / Wikimedia Commons (CC BY 2.0)

Robots, new ships and the next cable cut

The repair fleet is ageing faster than the network grows. The industry has roughly 60 ships able to repair a submarine cable. TeleGeography and Infra-Analytics found that about two-thirds of maintenance vessels will reach the end of their service lives by 2040, while total cable length grows by about 48 percent. Closing the gap would take some $3 billion, enough for fifteen replacement ships plus five more to keep pace. New hulls are coming, including the two ABB-equipped Orange Marine ships and a Global Marine vessel being built in Sri Lanka for 2029, but cable maintenance is paid for through shared agreements built to be cheap.

Two ABB Azipod propulsion units waiting for assembly at the Arctech Helsinki Shipyard, 2016. Photo: Petri Krohn / Wikimedia Commons (CC BY-SA 4.0)

Robot arms could follow on board, though we found none working in a jointing cabin today. Splicing fibre, testing it and rebuilding a pressure-tight joint is small-parts work of the kind ABB's YuMi does in factories. At the connector maker Radiall, a YuMi picks ceramic ferrules and metal ferrule holders from two flexible feeders and places them under a press, as our post on fiber optic manufacturing describes. Radiall wanted quick changeovers and no damage to delicate parts, and a cable joint calls for the same care.

ABB's dual-arm YuMi IRB 14000 working beside a lab technician. Photo: ABB

Out on deck the conditions are harder. ABB sells the IRB 1300 in IP67 and Foundry Plus 2 versions that seal all electrical components, and pitches them for tough environments with high levels of liquids and dust. The Foundry Plus 2 version also has a stainless steel end effector, so it does not rust when parts are washed down. A robot handling cable ends or test gear on a repair ship would also have to cope with the ship's motion, and no ABB arm does that job today. These remain possibilities, best tried first in RobotStudio simulation.

An ABB IRB 1300 in its Foundry Plus 2 version, with sealed electrical parts, inside a production cell. Photo: ABB

Nobody obviously owns the $3 billion bill, and permission is a second bottleneck: the longest repair recorded in 2023 took 947 days because of a wait for permission to carry it out. Security adds pressure, though the outcomes so far are mixed. A Finnish court dismissed the case against the captain of the Eagle S in October 2025, and US and European officials judged several Baltic incidents to be accidents. Then there are the people. Global Marine says its maintenance work relies on qualified experts as well as ships and ROVs, and ABB designed its GoFa cobots so users need not rely on in-house programming specialists. For households the stakes are plain, since The Telegraph's sources warn that a concerted sabotage campaign could cause phone and internet blackouts.

An ABB GoFa CRB 15000 cobot being guided by hand at an assembly table. Photo: ABB

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