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At Tong Fuk, FLAG is encased in pipe out to a distance of some 300 meters from the beach manhole. When the divers have got all of that pipe bolted on, which will take a week or so, they will make their way down the line with a water jet that works by fluidizing the seabed beneath it, turning it into quicksand. The pipe sinks into the quicksand, which eventually compacts, leaving no trace of the buried pipe.
Beyond 300 meters, the cable must still be buried to protect it from anchors, tickler chains, and otter boards (more about this later). This is the job of the two barges we saw off Tong Fuk. One, the Elbe, was burying FLAG. The other was burying APCN. Elbe did its job in one-third the time, with one-third the crew, perhaps exemplifying the difference between FLAG's freelance-based virtual-corporation business model versus the old club model. The Elbe crew is German, British, Filipino, Singaporean-of-Indian-ancestry, New Zealander, and also includes a South African diver.
In the center of the barge is a tank where the cable is spooled. The thick, heavy armored cable that the Elbe works with is covered with a jacket of tarred jute, which gives it an old-fashioned look that belies its high tech optical-fiber i
The injector is a huge steel cleaver, 7 meters high and 2 or 3 meters broad, rigged to the side of the barge so it can slide up and down and thus be jammed directly into the seabed. But instead of a cutting blade on its leading edge, it has a row of hardened-steel injector nozzles that spurt highly pressurized water, piped in from a huge pump buried in the Elbe's engine room. These nozzles fluidize the seabed and thus make it possible for the giant blade to penetrate it. Along the trailing edge of the blade runs a cha
The Elbe has its own tugboat, the Ocean East, staffed with an Indonesian crew. Relations between the two vessels have been a bit tense because the Indonesians butchered and ate all of the Elbe's laying hens, terminating the egg supply. But it all seemed to have been patched up when we were there; no one was fretting about it except for the Elbe's rooster. When the Elbe is more than half a kilometer from shore, Ocean East pulls her along by means of a cable. The tug's movements are controlled from the Elbe's bridge over a radio link. Closer to shore, the Elbe drops an anchor and then pulls itself along by winching the line in. She can get more power by using the Harbormaster thruster units mounted on each of her ends. But the main purpose of these thrusters is to provide side propulsion so the barge's movements can be finely controlled.
The nerve center of the Elbe is a raised, air-conditioned bridge jammed with the electronic paraphernalia characteristic of modern ships, such as a satellite phone, a fax machine, a plotter, and a Navtex machine to receive meteorological updates. Probably the most important equipment is the differential GPS system that tells the barge's operators exactly where they are with respect to the all-important Route Position List: a series of points provided by the surveyors. Their job is to co
Hey, wait a minute, the hacker tourist says to himself, I thought AT&T was the enemy. What's an AT&T guy doing on the bridge of the Elbe, side-by-side with Dave Handley?
The answer is that the telecom business is an unfathomably complicated snarl of relationships. Not only did AT&T (along with KDD) end up with the contract to supply FLAG's cable, it also ended up landing a great deal of the installation work. Not that many companies have what it takes to manage an installation of FLAG's magnitude. AT&T is one of them and Nynex isn't. So it frequently happens at FLAG job sites that AT&T will be serving as the contractor, making the local contacts and organizing the work, while FLAG's presence will be limited to one or two reps whose allegiance is to the investors and whose job it is to make sure it's all done the FLAG way, as opposed to the AT&T way. As with any other construction project from a doghouse on upward, countless decisions must be made on the site, and here they need to be made the way a group of private investors would make them - not the way a club would.
If FLAG's investors spent any time at all looking into the history of the cable-laying business, this topic must have given them a few sleepless nights. The early years of the industry were filled with decision making that can most charitably be described as colorful. In those days, there were no experienced old hands. They just made everything up as they went along, and as often as not, they got it wrong.
Thomson and Whitehouse
As of 1861, some 17,500 kilometers of submarine cable had been laid in various places around the world, of which only about 5,000 kilometers worked. The remaining 12,500 kilometers represented a loss to their investors, and most of these lost investments were long cables such as the ones between Britain and the United States and Britain and India (3,500 and 5,600 kilometers, respectively). Understanding why long cables failed was not a trivial problem; it defeated eminent scientists like Rankine and Siemens and was solved, in the end, only by William Thomson.
In prospect, it probably looked like it was going to be easy. Insulated telegraph wires strung from pole to pole worked just as one might expect, and so, assuming that watertight insulation could be found, similar wires laid under the ocean should work just as well. The insulation was soon found in the form of gutta-percha. Very long gutta-percha-insulated wires were built. They worked fine when laid out on the factory floor and tested. But when immersed in water they worked poorly, if at all.
The problem was that water, unlike air, is an electrical conductor, which is to say that charged particles are free to move around in it. When a pulse of electrons moves down an immersed cable, it repels electrons in the surrounding seawater, creating a positively charged pulse in the water outside. These two charged regions interact with each other in such a way as to smear out the original pulse moving down the wire. The operator at the receiving end sees only a slow upward trend in electrical charge, instead of a crisp jump. If the sending operator transmitted the different pulses - the dots and dashes - too close together, they'd blur as they moved down the wire.
Unfortunately, that's not the only thing happening in that wire. Long cables act as ante