Undersea Warfare The Official Magazine of the U.S. Submarine Force

Summer 2004 Cover of Undersea Warfare Magazine

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Summer 2004/Archives

U.S. Submarine... Beacause Stealth Matters


Washington Watch


Operational Depth

Ships At Sea

Letters to the Editor


6th Annual Undersea Warfare Photo Contest Winners

Former Commander-in-Chief Christens PCU Jimmy Carter

Hard-charging and Persistent: The Crew of PCU Virginia Looks Ahead

Pacific Reach 2004
U.S. Foreign Navies Practice Submarine Rescue, Foster Cooperation and Improve Interoperability

SSGN Conversions: Embodying the Sea Power 21 Vision

Heading North!
Traveling the Artic Region, U.S. Submarines Find Adventure, New Challenges, and New Friends

Saviors and Suppliers: World War II Submarine Speacial Operations in the Phillippines

Enhances Stability and Increases Interoperability in the Pacific Rim

Those in Peril - the S-5 Incident

Bringing Science to Life
Teaching Science Using Submarine Technology and the ex-USS Narwhal (SSN-671)

2004 Force Organization Map

Submarine Force Links

Director, Submarine Warfare

Commander, Naval Submarine Forces

Commander, Submarine Force Pacific Fleet

Navy News Stand

Undersea Warfare Photo Contest



Undersea Warfare 2003 CHINFO Merit Award

SSGN Conversions: Embodying the Sea Power 21 Vision

Photo caption followsThe Ohio-class submarine USS Michigan (SSBN-727) enters the intermediate maintenance facility at the Puget Sound Naval Shipyard for an engineered refueling overhaul and conversion into a guided missile submarine (SSGN).

The U.S. Navy is passing through a time of fundamental change. Older ships and weapon systems that were developed primarily to counter blue-water Cold War threats, with two superpowers butting heads for naval dominion, are now giving way to more modern, versatile designs. Moreover, the demise of the Soviet Union, combined with the rise in global terrorism, has prompted the Navy to shift its focus to the littorals and adopt the Sea Power 21 concept as a fundamental doctrine. An excellent example of the effects of this change on force structure can be found in the SSGN conversion program.

The SSGN embodies the offensive capabilities of SeaStrike, with the ability to launch up to 154 Tomahawk cruise missiles from 22 of her 24 former TRIDENT missile tubes. That is 32 more vertically-launched missiles than are carried on the latest Ticonderoga-class cruisers and 58 more than on Flight IIA Arleigh Burke-class destroyers.

Although generally, older ships are being phased out and replaced by new counterparts as they reach the end of their service lives, an interesting exception within one warship class is already in progress on a much more compressed schedule. The 1994 Nuclear Posture Review concluded that the Navy will need only 14 of its 18 USS Ohio (SSBN-726)-class ballistic missile submarines to adequately provide the seaborne strategic deterrent that is the nation’s most secure nuclear option. Rather than simply scrapping the four oldest boats – Ohio, USS Michigan (SSBN-727), USS Florida (SSBN-728), and USS Georgia (SSBN-729) – still highly-capable submarines with 80-plus years of total operational life remaining, the Navy decided to convert these ships into stealthy guided-missile strike and Special Operations Forces (SOF) platforms. Currently, Ohio is scheduled to complete conversion in November 2005, three years to the month after she began a preliminary overhaul and two years after beginning actual conversion. Florida began her preliminary overhaul in August 2003 and is scheduled to complete in April of 2006. Michigan recently entered drydock in March 2004 for her overhaul, and will complete her conversion in October 2006. Finally, Georgia will begin her overhaul in March 2005 and will complete the conversion process in September 2007, about the same time Ohio reaches Initial Operational Capability (IOC).

The SSGN conversions are designed to provide Navy leaders a strike platform capable of fulfilling multiple roles easily and effectively, while at the same time minimizing cost by leveraging existing hulls and their original builder’s inherent knowledge of the platform. Since the Electric Boat Division of General Dynamics built all the Ohio-class SSBNs, the company can use its prior experience and detailed familiarity with the submarines to take the lead in redesigning and converting them quickly and efficiently to the new configuration.

Photo caption follows

USS Ohio (SSBN-726) undergoes conversion from a ballistic-missile submarine (SSBN) to a guided-missile submarine (SSGN). By FY 2007, all four SSGNs, Ohio, Michigan, Georgia, and Florida, are scheduled
to have completed conversion. Ohio is scheduled to attain initial operational capability by 2007.

Sea Power 21’s principal elements are Sea Strike, Sea Shield, Sea Basing, Sea Warrior, Sea Trial, and Sea Enterprise. These are all tied together through FORCEnet, which subsumes the networks and communication systems that are designed to give naval leaders an all-encompassing, real-time picture of the battlespace. Sea Strike embodies offensive capabilities within Sea Power 21. It provides the means to conduct sustained, precision attacks on targets both at sea and inland. The SSGN will excel in this arena, with the ability to launch up to 154 Tomahawk cruise missiles from 22 of her 24 former Trident missile tubes. That is 32 more vertically-launched missiles than are carried on the latest Ticonderoga-class cruisers and 58 more than on Flight IIA Arleigh Burke-class destroyers. The SSGN’s other two tubes have been redesigned to accommodate dual five-man lock-in/lock-out chambers so Navy SEALs can exit the submarine while submerged and perform their own strike missions. At a time when the United States military is hunting terrorists in remote locations all over the globe, being able to covertly launch a large number of precision-strike missiles or deploy dozens of the world’s best sea-borne warriors provides the Navy with extraordinary stealth and powerful new capabilities.

The defensive focus of Sea Power 21 is called Sea Shield. Its purpose is to defend American territory, warfighters, friends, and allies, anywhere in the world’s oceans and littorals. Thanks to their stealth and current plans to exchange crews at forward bases, the SSGNs will be able to deploy in-theater longer than almost any other Navy asset. Combined with their state- of-the-art Intelligence, Surveillance, and Reconnaissance (ISR) capabilities for detecting and reacting to enemy threats, the SSGNs will quickly become one of the Navy’s crucial Sea Shield elements. Furthermore, the ships’ modular missile tubes will be able to host a variety of other systems, including remote mine-hunting unmanned underwater vehicles (UUVs) and possibly even unmanned aerial vehicles (UAVs), thus greatly increasing their defensive capabilities.

The SSGNs’ incredible size and mission flexibility will make them perfect platforms for Sea Basing. Sea Basing emphasizes extending the Navy’s reach and sustainability by using self-sufficient, mobile at-sea bases in forward areas. Each SSGN will provide just such a sea base for up to 66 Navy SEALs. In addition to the dual lock-in/lock-out chambers mentioned above, each boat will also have the ability to host two Dry Deck Shelters (DDS), two Advanced SEAL Delivery Systems (ASDS), or one of each. With all these options for deploying Special Operations Forces (SOF), SSGN becomes essentially a mobile SOF operating base right under the adversary’s nose.

Georgia  Prepares for Silent Hammer

In October 2004, the Navy will conduct a follow-on Sea Trial experiment called “Silent Hammer” off San Diego. Building on the success of “Giant Shadow,” “Silent Hammer” will test several new technologies, including the Flexible Payload Module and the Stealthy Affordable Capsule System (SACS), installed aboard “Silent Hammer’s” SSGN stand-in, Georgia. These features will give the submarine a more flexible interface with the sea for facilitating the off-load of weapons and unmanned vehicles.

The exercise will also test an SSGN’s effectiveness in a more “Joint” scenario, with networked forces at sea, in the air, and on land. This will be directed from Georgia’s newly-installed Battle Management Center, which will allow an embarked Joint Commander to make real-time, theater-wide command decisions from underwater. As in “Giant Shadow,” “Silent Hammer” will test an SSGN’s ability to transport and deploy SEALs and unmanned vehicles to a target zone. Georgia will again launch simulated Tomahawk missiles at land targets, but this time with the added complexity of coordinating the attack with a Marine Expeditionary Strike Group, which will also provide targeting information.


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