Powerful earthquakes near Taiwan shut off international phone and Internet service for the Far East just after Christmas. Five repair ships have been working on the damaged undersea cables since late last week. How do you repair a cable that’s lying across the ocean floor?
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… can zero in on more specific coordinates by sending light pulses along the fibers in the cable… a broken one will bounce it back from the site of the damage. By measuring the time it takes for the reflections to come back…
… If the faulty part of the cable is less than about 6,500 feet down, the crew will send out a submersible tanklike robot…
The robot doesn’t work in very deep water (with very high pressure). In those situations, the technicians aboard the cable ship use a grapnel, or a hook on a very long wire, to snatch up the cable from the sea floor. The grapnel uses a mechanical cutting and gripping device that can split the cable on both sides of the break and drag the loose ends to the surface. One end is hooked onto a buoy so it won’t sink, and the other is hauled on board.
