If they find another submarine at this time, it will be reported quickly, and action will be decided upon by higher authority. More likely, though, is the scenario in which a hostile submarine is waiting just outside the twelve-mile limit of American territorial waters. In this case the Los Angeles will probably try to sit astride the planned route of the Ohio and wait for any sign of activity. If such contact occurs, the action that follows might go something like this:
As the Ohio comes out (escorted by support and security vessels to keep, if nothing else, the Greenpeace protesters at a safe distance) and prepares to dive, the Los Angeles continues its job of sanitizing the ocean ahead of the boomer. Much like a sheepdog herding a flock, its job is to interpose itself between the SSBN and any threat until the boomer can slip quietly into the deep waters off the Carolina/Georgia coast. Once an Ohio is free of the continental shelf, even the latest 688I-class SSN would find it almost impossible to track.
The Los Angeles continues ahead of the boomer, until it gets the first "sniff" of a hostile sub. Then the engagement takes on all the aspects of a game of chicken with tractor-trailer trucks. The Los Angeles closes with the threat boat, trying to get it away from the Ohio with everything short of actually ramming it or firing weapons. The SSN initiates maneuvers conforming to the rules of the road, which require the hostile boat to evade. The American SSN might launch noisemakers and other countermeasures in an attempt to make so much noise that the Ohio will be lost in the background. Another technique has the Los Angeles masking the Ohio by standing along the path between it and the hostile sub, and blasting away with its spherical sonar array as a jammer.
If the threat sub proves to be particularly obnoxious, the American skipper might even engage in a maneuver to force the hostile boat's skipper either to take evasive action or suffer the possible damage and embarrassment of an underwater fender bender. Whatever maneuvers the attack boat chooses, the desired result is that by now the Ohio has slipped into the deep waters off the continental shelf and is silently on the way to her designated patrol area. Once this is accomplished, the Los Angeles probably breaks off the chase and heads for home.
Thus begins another in the more than 3,000 FBM patrols that the United States has run over the last three decades. The SSN will have helped make it a successful one, that is, one in which the boomer returns to base with all twenty-four of its missile tubes still loaded, missiles unfired. Some might claim that the above scenario is only the wildest speculation and conjecture, and perhaps this is true. But just what was that Victor III that surfaced off the Carolina coast in 1983 doing there? Just remember that the submarine bases at Charleston, South Carolina, and Kings Bay, Georgia, are right in that neighborhood. Do you think the Victor was there just to photograph the resort at Hilton Head? Hardly.
Tactical Example — Hunting a Diesel Submarine
One of the few growth industries in the defense world today is the diesel-electric submarine market. Since the end of the Cold War, more and more small- to mid-size navies have seen these compact, cost-effective craft as a way to make up for whatever protection they may have enjoyed from whichever side they allied themselves with during the Cold War. Unfortunately, because of cutbacks in the defense industry worldwide, some of the nations that produce such boats have sold their wares to nations that the rest of the world might consider somewhat less than responsible. China, India, Pakistan, Iran, and Algeria are just a few of the countries that have decided to invest heavily in diesel boats.
Surely the Volkswagen of the current generation of diesel boats is the Kilo-class boat produced by the CIS/Russia. This trim little boat is compact, has a good combat system, adequate weapons and sensors, and is very quiet. This makes it an excellent candidate for operations in straits and other choke points. In addition, a well-handled Kilo is almost impossible to detect passively when she is running on her batteries. And so our little story begins.
Let us suppose that the Islamic fundamentalist movement takes a serious hold in Algeria, along the coast of North Africa. And let us again suppose that the local ayatollah decides the merchant traffic passing along his coast should have to pay some duty for the privilege. It might then be possible that the Algerian Navy, the recent recipient of several Kilo-class boats, will be ordered to give the western merchants a demonstration of what might happen if they do not comply with the wishes of the new Islamic government.
An ideal way would be to seal the nearest choke point, then try to collect reparations to refrain from doing it again. For a cash-starved country like Algeria, this toll might be considered an excellent way to generate capital. The likely place for this demonstration would be the Straits of Gibraltar. Not only is it an ideal place for a diesel boat to operate, but the symbolism of doing it under the nose of the British Empire would be tough to resist.
The first notice of what was happening would probably be the "flaming datum" of an exploding merchant ship. Most modern torpedoes are designed to explode under the keel of the target ship, snapping it in two. If this were done to a tanker, for example, there would likely be a massive oil spill and fire, as well as wreckage that might float as a hazard to navigation for some time. This, combined with the inevitable declaration from the Algerian government, would undoubtedly cause a reaction from the Western powers. For hundreds of years Great Britain has held control of the seas around Gibraltar, and any mischief in the area would probably make them want to deal with it themselves. The likely candidate for this ASW extermination job would be a Trafalgar-class nuclear boat, because of its ability to deploy rapidly to the area threatened by the Algerian Kilo. Most folks do not realize that a diesel boat is actually just a mobile minefield. It simply does not have the strategic mobility or sustained speed of a nuclear boat, a simple fact that is lost on critics of nuclear submarines.
The deploying T-boat is likely to have some help in the form of RAF Nimrod ASW aircraft. In addition, it is a safe bet that the British have seeded the straits with a variety of acoustic sensors, and the area is about as wired as a pinball machine. The problem for the British hunters is the adverse noise conditions in the straits. There are several thermal layers, which make passive sonar almost useless. In addition several currents, overlapping and opposed in direction, generate a lot of flow noise. All in all, the Straits of Gibraltar is a miserable place for passive ASW hunting.
Fortunately, though, the nuclear submarine has another advantage over the diesel boat besides sheer mobility. That advantage is the huge active sonar array positioned in the bulbous bow of the boat, which is able to send out pulses of sound and bounce them off a target submarine. A special operating mode makes it even more effective: in areas with relatively flat, hard bottoms, a technique called "bottom bounce" can be used. Much like skipping a stone across the water, an active sonar can bounce sound waves off the bottom to contact another submarine. Using this technique, a nuclear submarine might contact an almost-silent diesel boat at ranges beyond 10,000 yards. And as an added benefit, because of all the reverberations from the sound waves bouncing off the seabed, the target submarine probably will not be able to tell what direction the active signal is coming from.