Raising The Kursk

A year after the Russian nuclear submarine Kursk mysteriously exploded and sank with 118 sailors aboard, an international team is trying to raise the vessel--or most of it--to the surface. This week salvagers are scheduled to begin the dangerous process of slicing off the heavily damaged torpedo compartment, which would be left on the sea floor along with the answers it may contain.

THE SCENE ABOVE

A 459-ft. barge from the Netherlands, the Giant 4, will anchor over the sub. The barge is being fitted with lifting equipment and underwater "saddles" to hold the sub in place

THE SCENE BELOW

The Kursk is 377 ft. below the surface. Salvagers have calculated that the submerged vessel weighs more than 21 million lbs. The water temperature hovers just above freezing. While the salvage concept is simple--attach some cables and pull up the sub--the challenges are formidable

1 DRILLING HOLES Divers using high-pressure hoses are cutting 26 holes through the outer and inner hulls of the sub and attaching cones and wires to guide the cables. The holes are 27.5 in. wide

2 REMOVING FRONT COMPARTMENT A remote-control device--sort of a giant chainsaw--will attempt to slice down through the sub, severing the 65-ft. front compartment. There have been conflicting reports on the presence of unexploded torpedoes in this area

3 INSERTING PLUGS Specially designed plugs will be lowered from the barge and inserted into each hole in the sub. The plugs work like giant toggle bolts, expanding once they have passed through the holes in the hull. Each plug has been shaped for its specific spot along the sub

4 FREEING THE SUB The sub has sunk 3 ft. to 6 ft. into the silty bottom. Salvagers intend to lift the tail of the sub first in hopes of breaking the suction

5 LIFTING JACKS The 26 lifting jacks on the Giant 4 are controlled by computer to keep them operating in unison. Their frames can move vertically to compensate for rolling seas. Each jack pulls in a small section of cable at a time, for a total of about 33 ft. an hour. If all works as planned, the lift will take about 11 hours

6 GETTING INTO DRY DOCK Once the Kursk is held fast to the Giant 4, a tugboat will begin the long pull to dry dock in Roslyakovo, Russia. There, two additional water-filled pontoons will be attached alongside the barge and sub

As water is pumped out of the pontoons, the ships should rise high enough in the water to fit into the dry dock. Tugboats will guide the unwieldy craft into place. In the dock, the cables to the Kursk will be lowered, the plugs removed and the sub released Tugboats will then pull the Giant 4 and the pontoons out of the dry dock. The dock holding the sub will then be raised from the water.

Later, what's left of the Kursk will be towed to another shipyard, where it will be defueled and scrapped

NUCLEAR DANGER The two nuclear reactors on the Kursk are believed to be shut down, and Russian officials say no radiation leaks have occurred. But significant risks remain, both during the salvage operation and during the eventual delicate removal of the nuclear fuel

Sources: Mammoet Smit International, Bellona Foundation, DSND, Central Design Bureau for Marine Engineering, Strana