Nothing so chills the U.S. Navy as an incoming cable sounding the alarm over a DISSUB--a disabled U.S. submarine--stranded somewhere on the ocean floor. That's why, following the loss of the U.S.S. Thresher in 1963 with 129 men aboard, the Navy launched its SUBSAFE program. It's designed to wring as much danger as possible out of the inherently risky business of prowling the world's oceans. The program isn't perfect. In 1968, the U.S.S. Scorpion went down, killing all 99 aboard. But those 228 Americans lost are fewer than half the number of Russians killed--excluding those who perished in the Kursk--while serving in Moscow's nuclear-submarine force.
A U.S. sub hasn't been lost for more than 30 years because of a rigorous certification program that gives each key piece of a submarine--including its hull, pipes, valves and flood barriers--a serial number pinpointing its source and whom to hold accountable if it fails. Critical systems are duplicated. For example, there are three ways to empty the ballast tanks on Trident missile boats. U.S. submarine crews are repeatedly drilled, ashore and afloat, with two key aims: to keep their sub safe and, if that fails, to get out alive. The top concerns for crews include knowing how to restrict flooding once the hull has been breached and how to put out a fire.
U.S. submariners say they drill more often and more realistically than their Russian counterparts. While Russian submariners have rushed to automate much of their onboard machinery, the U.S. Navy still relies heavily on men in the loop standing watch to keep their vessel humming and safe.
There are smaller safety concerns as well. Only iron-based metals can be ground on a submarine's grinding machine because other metals can leave a residue on the wheel, triggering imbalances that could lead to its dangerous disintegration. Only Navy-approved multi-outlet power strips are supposed to be brought onboard. Every clothes iron must have a three-prong plug.
The reams of regulations lead to lots of violations. A recent Navy survey found that 62% of U.S. submarines stored flammable liquids improperly, increasing the chance of a fire. And 57% of them had nonapproved multi-outlet power strips. More than 30% of the subs were missing basic lifesaving equipment--such as nose clips, whistles and fluorescent sea markers--that sailors would need if they had to escape from their submarine individually.
Trouble can still crop up unexpectedly. In March, a warning flare exploded in its launch tube in a submerged Navy submarine. The blast sheared a dozen bolts holding the launcher in place and let seawater flow into the bow compartment. There were no injuries, and the Navy has now barred the use of that kind of flare.