This space is also where the air is made or, more properly, maintained. Several different pieces of equipment in the auxiliary machinery space help to provide the clean, fresh air that can be found onboard. First are the carbon dioxide (CO) scrubbers. CO is the gas given off by humans when they breathe and is dangerous when the concentration gets too high. The Miami utilizes a chemical scrubber to remove it from the air. The chemical absorbs CO when it is cool and releases it when it is warmed. In addition, CO and H "burners" remove the carbon monoxide and hydrogen gas generated by equipment as well as by cigarette smoking, which is allowed onboard. Finally, filters and dehumidifiers clean the air and help keep it "friendly" not only for the crew but also for the many pieces of equipment-especially electronic-on the Miami. In case a fire or some other emergency contaminates the onboard air, a force-fed air supply called the Emergency Air Breathing (EAB) system has attachment points throughout the boat, allowing crewmen with breathing masks to plug in to it and continue their duties.

  Other life support equipment includes a device that takes water and electrically "cracks" it into its base elements of hydrogen and oxygen. The oxygen is retained in tanks and released into the boat's atmosphere automatically by the environmental control system, and the hydrogen is vented off the ship from a small port in the aft edge of the fairwater. There is a fresh-water distillation plant that produces something over 10,000 gallons/38,000 liters of fresh water a day. Most of the water is used for drinking, cleaning, cooking, and personal hygiene. Very little water is usually required for the power plant (for charging the cooling loops and steam generators), but the reserve tanks are usually maintained near full "just in case." It should be said that the obsession with water conservation is mostly for contingency purposes. Most COs like to have full tanks of water before they enter a tactical situation, just in case they need to shut down the distillation plant to keep noise down. And from what I hear, some boats just choose to run the distillation plant full-time and let the crew have as much shower time as they want, particularly during runs home. On a normal day aboard Miami, the majority of the water produced would go to crew habitability.

  Weapons-Torpedoes, Missiles, and Mines

  While submarines are useful for covert actions like intelligence gathering and landing special operations forces, it is the threat of what they can do with their weapons that can cause so much fear and respect in an adversary. Ever since Sergeant Ezra Lee tried to sink HMS Eagle in Boston harbor back in 1776, just the potential threat of harm from a submarine has been enough to make an enemy stop and consider whether he should move his ships against you. Today the weapons can hit a wider variety of targets, and they have become even more deadly.

  Torpedoes

  The torpedo is the traditional weapon of the submarine, and the torpedoes that equip the U.S. SSNs today are truly awesome. For some years now, the U.S. standard torpedo has been the Mark (Mk) 48. This weapon, which first appeared in 1971, has gone through a series of different upgrades, culminating in the Modification (Mod) 4 version, which appeared in 1985. This version, designed as an intermediate upgrade to the next major version, allows for the greater speeds and deeper diving depths of the newer Soviet subs that were appearing at the time. As this book is written, about half the torpedoes being loaded aboard U.S. subs are Mk 48 Mod 4s.

  Cutaway view of a Mark 48 advanced capability (ADCAP) torpedo. JACK RYAN ENTERPRISES, LTD.

  The business end of a Mark 48 ADCAP torpedo. The black cover is the acoustic "window" of the torpedo's seeker head. JOHN D. GRESHAM

  A recent addition is known as the Mk 48 Advanced Capability (ADCAP) torpedo. Manufactured by Hughes, the ADCAP takes the basic Mk 48 package and adds the following new features:* A bigger fuel tank that provides for a 50 percent increase in range (about 50,000 yards), and a speed of 60+ knots.* A new data send/receive module, which packs 10 miles of guidance wire into the aft end of the torpedo and 10 more miles into the dispenser in the tube. This allows the submarine to clear the launch point and still guide the weapon.* A new combination seeker head/computer that uses electronically steered sonar beams to guide the weapon to the target. Earlier versions of the Mk 48 (like the Mod 4) used to have to "snake" about their course to search effectively for a target. The head allows the torpedo to see almost all the 180-degree hemisphere ahead of the weapon. The computer controlling the whole system is designed to make the ADCAP the world's "smartest" torpedo.

  Tail section of an Mk 48 ADCAP torpedo. Inside the cover (labeled No Step) is the pumpjet propulsor, and a dispenser for ten miles of guidance wire. The silver unit behind it, which stays in the tube, contains another ten miles of wire. JOHN D. GRESHAM

  The back end of an R/UGM-84D Harpoon antiship missile. The locked cover, which protects the guidance fins, is removed prior to loading. JOHN D. GRESHAM

  With ADCAP, the submarine force arguably has the finest torpedo in the world. Not only is it fast, deep diving, and maneuverable, but it has a big warhead (650 lb/295 kg of PBXN-103 explosive) with an active electromagnetic fuse that allows the weapon to be detonated precisely where it will do the most damage. And it has more "brains" than any other torpedo, with an amazing ability to outsmart countermeasures and jamming, as well as the capability to feed seeker-head data back to the BSY-1 system on Miami. This allows the fire control technicians to use the ADCAP as an offboard sensor. With such capabilities as these, it's no wonder that the crew of Miami calls the ADCAPs in her racks "wish me dead" torpedoes.

  Missiles

  Strange as it may sound, the nuclear submarines of the U.S. Navy operated for over twenty years without a dedicated weapon for attacking surface ships. Part of the reason was the ASW focus of the SSN force during the 1960s and 1970s. Also, for much of that time their primary targets, the surface ships of the USSR, had no long-range weapons that could attack a sub while it was submerged. But with Soviet deployment of their first sea-based ASW helicopters and the ship-launched SS-N-14 Silex ASW missile, there was a clear need for a weapon that would allow a boat to stand off farther than the ten to fifteen miles a torpedo shot would allow. It had to be launched from a torpedo tube and carried as an all-up or "wooden" round, requiring no maintenance and a minimum of support.

  Cutaway view of an R/UGM-84D Harpoon antiship missile. JACK RYAN ENTERPRISES, LTD.

  Encapsulated UGM-84 surface-to-surface Harpoon antiship missile leaving the capsule as it clears the surface of the water. OFFICIAL U.S. NAVY PHOTO

  The weapon that was produced was the McDonnell Douglas A/R/UGM-84 Harpoon. This missile, which can be launched by ships, subs, and aircraft, was originally developed to allow patrol aircraft to shoot at Russian cruise missile subs on the surface. First deployed in 1977, it is approximately 17 feet/5.2 meters long, weighs about 1,650 lb/750 kg, and carries a 488-lb/222-kg high-explosive warhead. It utilizes a radar seeker that looks for surface targets and then initiates an attack "endgame" on the target. Packaged inside a buoyant, torpedo-shaped launch capsule, it is fired from one of the normal torpedo tubes and rises to the surface. When it reaches the surface, the nose of the capsule is ejected, and the missile is launched into the air by a small rocket booster. Once airborne, the booster is dropped, an engine inlet cover is ejected, and the small turbojet engine is ignited. The missile then descends to about 100 feet above the surface, and transits to the area of the target ship at a speed of about 550 knots.

  The Harpoon can be launched in a variety of modes. These include what is known as Bearing Only Launch (BOL), in which only the bearing to the target is known. There is also a series known as Range and Bearing Launch (RBL) modes, which require both range and bearing. Depending on the range to the target and the amount of neutral shipping in the area, the seeker can be set to RBL–L (Large) for open ocean situations, or RBL-S (Small) for tight, short-range situations. If necessary, several doglegs or waypoints can be programmed into the Harpoon's Midcourse Guidance Unit (MGU), which utilizes a small strapdown inertial guidance system to keep the missile on course. For submarines, there is even a self-defense option that allows the defending SSN to shoot the Harpoon "over the shoulder" into a charging surface ship.

  Once the missile gets to the target area, the seeker is switched on and begins to search an area shaped much like a piece of pie. If the seeker radar locates a suitable target, the onboard computer does a quick test to make sure it is a valid target (not a wave or a whale), and begins the endgame. The missile descends to an altitude between 5 and 20 feet (depending on the height of the waves) and heads for the target. At the discretion of the Miami's fire control technicians, the missile can be programmed to run straight into the side of the target ship (just a few feet above the waterline), or an optional "pop-up" maneuver can be selected to make the missile plunge deep into the middle of the ship.

  In any case, the exploding warhead will tear much of the guts out of any ship up to cruiser size. In addition, any of the jet fuel not used by the missile's turbojet will add to the destruction aboard the target vessel. It is a little-known fact that the warhead of the Exocet missile that sank HMS Sheffield in 1982 failed to detonate, but the residual rocket fuel in the missile's motor caused enough of a fire to eventually sink the ship.

  The latest version of Harpoon aboard the Miami is the UGM-84D, which uses a denser fuel mixture to give it more range (reportedly around 150 NM/250 km). All in all, with some eighteen different countries using it, Harpoon is one of the most successful missile programs ever run by the U.S. Navy.

  After the ADCAP, no weapon has done more to make the Miami deadly and effective than the UGM-109 Tomahawk cruise missile. Tomahawk is an outgrowth of a loophole that was discovered after the signing of the SALT I arms limitation treaty in 1972. While the exact origin of the cruise missile program is debated, it is generally assumed that Henry Kissinger, then the National Security Advisor, asked the Department of Defense (DoD) to look for classes of nuclear weapons that had not been considered during the SALT I negotiations. After some study, the DoD systems analysts came to the startling conclusion that air-breathing cruise missiles, basically cheap pilotless aircraft with nuclear warheads, would make an excellent weapon to circumvent the terms of the SALT I agreement. They could be launched from ground vehicles, aircraft, ships, and submarines, would be extremely accurate, and would be quite difficult to detect and intercept.

  Target damaged by a Harpoon missile impact. OFFICIAL U.S. NAVY PHOTO

  As a result of these studies, a joint project office to develop cruise missile components was started by the U.S. Navy and U.S. Air Force. While both services wound up choosing different models of missile (the Air Force selected a model built by Boeing), most of the components such as engines, warheads, and guidance systems were of a common design. The winner of the Navy competition was the B/UGM-109 model developed by General Dynamics. McDonnell Douglas is the second-source contractor for the missile, called Tomahawk.

  Cutaway view of a Tomahawk land attack conventional (TLAM-C) cruise missile. Note the 1,000-lb high-explosive warhead. JACK RYAN ENTERPRISES, LTD.

  A Tomahawk cruise missile is launched from the USS La Jolla (SSN-701) on the Pacific Missile Test Center (PMTC) range. OFFICIAL U.S. NAVY PHOTO BY GERRY WINEY

  The basic nuclear land attack version of Tomahawk, known as B/UGM-109A (also called TLAM-N), is launched into the air by a small rocket booster. Once airborne, a miniature jet engine about the size of a basketball ignites to power the missile at about 500 knots. It flies low to the surface (whether over the open ocean or land), held there by a guidance unit (MGU) being fed by a radar altimeter. The missile is kept on course by the MGU utilizing an inexpensive strapdown inertial guidance system. Once over dry land, the MGU is updated with position data from a system known as Terrain Contour Matching (Tercom), which matches the terrain under the missile with a three-dimensional database in the memory of the MGU. By using periodic Tercom updates, a TLAM-N is normally able to place its 200-kiloton W-80 nuclear warhead between the uprights of a football goal-post after a 1,300-mile flight.

  While the nuclear-armed version of Tomahawk was being developed, it occurred to a number of people that perhaps the Tomahawk could be used to carry other things, and thus was born the whole family of conventionally armed Tomahawks in service now. The first of these was the B/UGM-109B Tomahawk Anti-Ship Missile (TASM), which replaced the TLAM-N MGU with a modified radar seeker and MGU from the A/R/UGM-84 Harpoon antiship missile. In addition, the W-80 nuclear warhead was replaced with a 1,000-lb/455-kg high-explosive warhead.

  The idea was to provide units of the U.S. Navy with a really long-range (250 NM/410 km) antiship missile. One problem that had to be overcome was the fact that a TASM flying out to hit a target ship at maximum range would have to fly almost thirty minutes to get to the target area. During this time, a fast warship might travel as far as fifteen to twenty miles, so a special series of search patterns was added to the TASM launch and control software. These search patterns comprise a series of "expanding boxes" designed to allow the TASM to fully search the uncertainty zone or the possible target area. In addition, TASM has a passive ESM system called PI/DF (Passive Identification /Passive Direction Finding), which is designed to direct TASM onto larger enemy warships, probably through detection of their large air-search radars.

  Following the TASM into service was the largest subfamily of the R/BGM-109 program, the Tomahawk Land Attack Missile-Conventional (TLAM-C) series. This particular series takes the basic guidance system of the TLAM-N, adds the high-explosive warhead of the TASM, and a new terminal guidance system called Digital Scene Matching (DSMAC). It has a range of roughly 700 NM/1,150 km, and uses the same basic Tercom system to get into the vicinity of the target. DSMAC is an electro-optical system that matches the image from a small television camera in the nose of the TLAM-C to one stored in system memory. This system can even be used at night, with a strobe light on the target during the final approach. Called the B/UGM-109C, it became the first of the Tomahawk series to be used in combat, during Operation Desert Storm.

  Several derivatives of the basic TLAM-C include the B/UGM- 109D, which replaced the basic high-explosive warhead with a dispenser for 166 BLU-97/B combined effects (fragmentation and blast) submunitions. Called TLAM-D, these Tomahawks are particularly effective against vehicles, personnel, soft targets, and exposed aircraft. A further variant of the TLAM-D, which is armed with antirunway cratering submunitions, is known as the B/UGM-109F. The newest version of Tomahawk, called Block III, incorporates a number of new features such as its own Navstar GPS receiver, a new penetration warhead, an improved engine, and more fuel to bring its range to over 1,000 NM/1,640 km. It should be operational in 1994.

  All the various types of Tomahawks can be loaded and fired from any 21-inch/533mm torpedo tube or VLS tube on the Miami. Besides twelve missiles in the VLS tubes, additional Tomahawk rounds, as required by a particular mission, can be stored in the torpedo room. This makes Tomahawk the most flexible strike system ever deployed by the U.S. Navy. It also opens a new dimension for the U.S. SSN force, since now they can join the surface and air forces in striking "over the beach" at significant targets.

  The following might be a typical mission load-out for the Miami. When preparing to leave for a cruise to the Mediterranean, she might carry a full load of Tomahawks, which would include twelve VLS tubes full of TLAM-C/D variants, with several more in the torpedo room racks. In addition, she would carry a mixed load of Mk 48 Mod 4s and ADCAPs, as well as several Harpoon Block ID antiship missiles. There would be no TLAM-Ns, as all of these have been withdrawn from U.S. ships, aircraft, and submarines following President Bush's order in the fall of 1991. Nevertheless, though it is the policy of the U.S. Navy not to deploy nuclear weapons, and they normally refuse to discuss it, the capability does still exist. Also, there would be no TASMs aboard, as the submarine community seems to feel that the Harpoon Block ID is more than adequate to the antishipping task, and the TASMs are hard to get long-range targeting for, on a submarine.

  The biggest single bottleneck to effectively utilizing the growing force of TLAM-C/D cruise missiles in the inventory is the preparation of suitable mission plans. Each mission plan has to be developed from a Tercom data base that the Defense Mapping Agency (DMA) has assembled over a period of fifteen years. The data is made into mission plans at one of the Theater Mission Planning Centers (TMPC) located at various places around the world. Here the Tercom data bases are merged with terminal target photos (for the DSMAC cameras), to produce mission plans that can be stored on disk packs on the sub, or downloaded to the sub via a satellite link.

  Once the Miami has a particular mission plan aboard, the basic plan can be modified on the BSY-1 Command and Control System (CCS Tac Mk 2) console in the control room. Located adjacent to the BSY-1 fire control consoles, this console can be used to plan and control missions for all the variants of Harpoon and Tomahawk. Should Miami not have a plan available in her onboard library, she can use the CCS-2 to develop her own plans. And with the coming deployment of the Block III version of TLAM-C, the requirement for access to a complete Tercom library for mission planning will be reduced.

  To launch a Tomahawk or Harpoon, the boat has to slow to about 3 to 5 knots and come to periscope depth. The CCS-2 (or BSY-1 in the case of Harpoon or TASM) console operator powers up and loads a mission plan into a missile loaded in either a torpedo or VLS launch tube. This can be done for as many or as few missiles as the situation requires. Once this is done, the weapons officer inserts a launch key (a holdover from the old TLAM-N days) and presses the firing button. If the weapon is a Tomahawk, it is ejected from the tube (the version fired from torpedo tubes is carried in a tube liner), fires its booster rocket, and away it goes. If it is a Harpoon, the weapon in its buoyant capsule is ejected from the tube and heads for the surface. When it gets there, the booster rocket fires, and it heads for the designated target.