The collision of two strategic nuclear submarines earlier this month shows that the Cold War is still being fought every day in the Atlantic -- with the world's most powerful weapons.
The world is a good and beautiful place, and on the Mull of Kintyre, it seems as peaceful as Paul McCartney described it in his 1970s megahit. Sheep graze on the hills of this peninsula in southwestern Scotland, and the valleys are filled with the scents coming from small distilleries that produce some of Scotland's best whiskey.
But two Saturdays ago, that illusion of peace was shattered when the HMS Vanguard, a British nuclear submarine, limped past the Mull of Kintyre enroute to its home port of Faslane. It quickly became clear that a nuclear catastrophe had almost occurred out at sea -- and that it could happen at any time, because the world is, of course, not a peaceful place after all.
There were dents and scratches on the hull of the Vanguard. It had collided in the Atlantic with the French submarine Le Triomphant. The incident was a highly improbable accident, and yet it nonetheless still happened.
The crash revealed that the Cold War is still being waged in the depths of the world's oceans, and that not even allies like Great Britain and France trust each enough to share information about the whereabouts of their most powerful weapons. It also showed that a giant submarine like the Vanguard, with its 16,000 tons of displacement, could conceal itself almost perfectly.
Vanguard and Le Triomphant aren't ordinary attack submarines -- they're rare and extremely expensive ballistic missile submarines. The British have four, as do the French, the Americans have 14, the Russians 15, and the Chinese are believed to have three. The hull of the Vanguard, as tall as a four-story building and roughly 150 meters (492 feet) long, contains a nuclear reactor and 16 ballistic missiles armed with nuclear warheads with a combined power more than 300 times greater than that of the atom bomb that destroyed Hiroshima.
"This is a very serious incident," says retired Royal Navy Commodore Stephen Saunders, the editor of the reference book "Jane's Fighting Ships." Experts at a British anti-nuclear organization call the accident a "nuclear nightmare."
Neither the British nor the French are willing to reveal when, where and exactly how it happened. The Triomphant is believed to have collided with the Vanguard while traveling at low speed. The French damaged the sonar dome located under the bow of their submarine. Even though highly sophisticated detection equipment is concealed under the dome, it apparently failed to detect the massive British submarine directly ahead.
Strategic submarines are high-tech weapons with an archaic mission: to exact revenge. And they are built for the day the world comes to an end. No matter how many of an enemy's land-based nuclear warheads they destroy, nuclear powers are hardly likely to track down its strategic submarines. The submarines, for their part, are designed to retaliate with such force that there can be no winners in a nuclear war.
Scientists are constantly coming up with new ways to locate and sink the submarines, but the problem is that none of these methods works reliably. For instance, although special detectors have been developed to detect the imprints such a large steel vessel makes in the earth's magnetic field, many external factors can interfere with the devices.
Infrared receivers can detect the heat generated by a nuclear reactor, but they also mistakenly identify the water being churned up behind a freighter as a submarine. Laser scanning beams cannot penetrate far enough beneath the surface. Bioluminescence detectors detect the light emitted by microbes agitated by a submarine's propellers, but the same microbes also emit light for other reasons.
That leaves sonar. So-called active sonar transmits "ping" noises into the water, and the resulting echo enables the sonar device to compute the location and size of a submarine. However, sound travels far underwater, and a submarine that transmits sound will be the first to reveal its location. This is why strategic nuclear submarines use passive sonar, a system of highly sensitive hydrophones that uses computers to convert underwater sounds into images of the dark depths.
The only problem is that submarines are extremely quiet, thanks to the use of special propellers and sound-insulated engines, and the commanders usually drive their submarines at no more than a walking pace. The super-weapons, says French Defense Minister Hervé Morin, make "less noise than a crab."
Another danger is that the ocean is a structured labyrinth for submarine pilots. Layers of water with different salinity levels mimic horizontal ramps and solid ocean floor, because the layers between them deflect sound. Warm currents build vertical walls in the same way. This creates safe spots in the middle of the ocean into which strategic submarine commanders like to embed their vessels, as well as hidden paths that tend to be used by all submarines.
This is why the British and the Americans coordinate the positions of their submarines. The French, however, keep themselves out of the loop. "France releases no information at all," says a navy spokesman, "because the nuclear arsenal is the absolutely decisive element of defense."
The recent crash, however, could spell an end to this secretiveness -- especially now that France will rejoin the NATO military command structure in April.
That leaves the Russians. The 173-meter (567-foot) Dimitry Donskoy, for example, is the world's largest strategic submarine. It has twice the displacement of the Kursk, which sank in 2000, and enough nuclear warheads on board for any conceivable disaster. According to the Russian daily Komsomolskaya Pravda, the Donskoy could "simultaneously destroy dozens of cities like New York, or level half of Afghanistan."