Submarine: A Guided Tour Inside a Nuclear Warship

presumed lost' were used to inform the world of a possible SSN loss during normal patrol operations.

^{USS Sturgeon (SSN-608). JACK RYAN ENTERPRISES, LTD.}

^{USS Los Angeles (SSN-688). JACK RYAN ENTERPRISES, LTD.}

While the exact method of location is still not openly known, it appears that the U.S. seabed-based sound listening (SOSUS) network heard an explosion from Scorpion. Later that year a survey expedition, utilizing the bathyscaphe Trieste, located the wreck near the Azores, relatively intact on the seabed. It was concluded her loss may have been due to an internal explosion, though the exact cause has never officially been announced.[4]

On a more positive note, the Navy built several new prototype submarines to explore new propulsion technologies. The USS Glenard P. Lipscomb (SSN-685) was designed to look again into the feasibility of using a turbine-electric drive, while the Narwhal (SSN-671) carried a prototype reactor using natural circulation rather than pumps, which can be very noisy, to move coolant through the reactor system. While they did provide useful data for future submarine designs, neither boat was considered to be particularly successful. With this lack of a propulsion breakthrough, the stage was set for the fight over the design of the next generation of nuclear submarines.

^{Nuclear-propelled strategic missile submarine USS Ohio (SSBN-726), during sea trials. OFFICIAL U.S. NAVY PHOTO BY WILLIAM GARLINGHOUSE}

The New Generation of Boats

In the late 1960s, the U.S. intelligence community began to receive disturbing indications that the nuclear submarines of the Soviet Union had much higher performance capabilities than previously thought. A debate broke out between Admiral Rickover at the Naval Reactors Branch and the Naval Sea Systems Command (Navsea) over the direction of the next generation of attack submarines. Rickover felt that what was needed was a quiet, high- speed (over 35 knots) attack submarine able to support the carrier battle groups deployed by the U.S. Navy. Navsea was supportive of a design called Conform, utilizing a natural circulation reactor, which would recover the speed loss of the Permits and Sturgeons (down from 30 knots to 25 knots) and improve the radiated noise levels.[5] Eventually Rickover won out, and a twelveship class, its lead boat to be named USS Los Angeles (SSN-688), was planned, with Electric Boat as the prime contractor.

^{First launch of a Trident C-4 missile from USS John C. Calhoun (SSBN-630). OFFICIAL U.S. NAVY PHOTO}

^{USS Ohio (SSBN-724). JACK RYAN ENTERPRISES, LTD.}

The Los Angeles-class boats delivered their promise of high speed as well as being the quietest attack submarines ever created up to that time. The price they paid for that speed was that their hulls were thinned; they could dive only to about three-fourths the depth of the Sturgeon and Permit classes (approximately 950 feet/300 meters).[6] In addition habitability suffered, with a greater percentage of the crew having to rotate bunks (called 'hot bunking'). Finally, the Navy and Electric Boat had significant financial and program management problems, along with a desire to expand the class more quickly, leading to a second-source contract for construction to Newport News-Tenneco. In spite of this, the first Los Angeles-class boats came on line in the late 1970s and immediately set new standards for quiet operations and speed. Some sixty-two Los Angeles- class boats would eventually be contracted, making it easily the largest class of nuclear submarines ever built.

In addition a whole new series of submarine weapons came on line in the late 1970s and 1980s, including the new Mod 4 and ADCAP versions of the Mark (Mk) 48 torpedo; the UGM-84 Harpoon antiship missile; and three separate versions of the R/B/UGM-109 Tomahawk missile for nuclear land attack, antiship use, and conventional land attack. All of these new weapons, combined with the addition of a vertical launch system and stowage for twelve Tomahawk missiles on the Los Angeles-class boats, suddenly made U.S. SSNs capable of a whole range of missions that Admiral Rickover had not dreamed of when he first pushed through the proposal for Nautilus in the 1950s.

The new class of boomer was somewhat clearer to design: the primary criterion was stealth. When the first boat of the new class, the USS Ohio (SSBN-724), appeared, she was reported to radiate less noise than the surrounding ocean and surface traffic, making the Ohios the quietest submarines ever to take to sea. Another major improvement was the number of missiles carried. All previous SSBNs produced by the United States had sixteen missile tubes. The Ohio class has twenty-four missile tubes, with a diameter large enough to accommodate not only the Trident C4 missile (the replacement for the Poseidon C3), but also the Trident D5 missile. The Trident D5 had significant improvements in both range and accuracy, making it the most powerful component in the U.S. nuclear arsenal. Under the terms of the START-II treaty signed in 1991, the bulk of the U.S. strategic nuclear strike power will be carried on the Ohios.

The Next Generation

With the coming of a new series of arms limitation treaties (the START series), the United States does not have any plans to build a new class of SSBNs. In fact, the Ohios were built with enough growth potential in their design that service lives of thirty-five to forty years are entirely possible, and if replacements are required, they won't be needed until around the year 2015.

Attack boats are another thing entirely. A follow-on to the Los Angeles class has been planned for some time, and the lead boat of the new class, USS Seawolf (SSN-21), is due to come on line in the late 1990s. The Seawolf design makes good virtually all the shortcomings of the Los Angeles-class boats, particularly in the areas of depth (back to approximately 1,300 feet/400 meters), habitability (improved crew comfort), and weapons load (a combination of fifty weapons).[7] Such things come at a severe cost though, both in money and size. Seawolf is huge, over 9,100 tons displacement, making it the largest attack submarine in the world other than the Russian Oscar-class guided missile boats. And with a cost at this writing of over $2 billion per copy, the Seawolf production run is currently limited to only two units.

As production of the Los Angeles and Ohio classes winds down, and with the Seawolf program being terminated early, the future of the U.S. nuclear submarine force is in doubt for the first time in forty-five years. What has been the premier weapons system of the Cold War now seems to be a system in search of a mission and an audience. We will explore the future later on, but first let's look at the present, and what the taxpayers have bought for themselves and their silent warriors.

Building the Boats