CGN-38 Virginia Class
The four Virginia class guided missile cruisers were equipped to fulfill multiple tasks in all warfare mission areas. The ships were equiped with two twin-rail missile launchers for AAW with ASROC capability; two 5" .54 caliber gun mounts for AAW and ASUW; two three-barrel torpedo launchers for ASW; and a LAMPS helicopter for ASW. Two pressurized nuclear reactors were capable of propelling the ship at speeds in excess of 30 knots, providing the endurance and capability to operate with other conventional and nuclear ships over extended periods of time and great distances. During the 1980s the ships were was outfitted with the Tomahawk Cruise Missile System, the Standard SM2(MR) Missile System, and the AN/SPS-49 Air Search Radar.
The design of these ships was the result of several influences in the ongoing program of surface combatants during the 1960's and early 1970's. They were an improved design, superior to their previous California class with a flush deck, the Mk 26 missile launcher and an embarked helicopter. The perfection of the Mk 26 guided missile launcher systems and the SM-1 Standard missile offered better performance in the face of electronic countermeasures, faster reaction times, and an increased kill probability. The SM-1 still used the continuous rod warhead, but with a new fuse whose sensing cones and digital electronics triggered it to cause maximum damage depending on whether the target was a surface ship, jet bomber, or cruise missile.
Also under development was the SM-2 missile with a range of 100 miles and a programmable autopilot. Although SM-2 was intended principally for Aegis ships, the Terrier and Tartar vessels could benefit from this asset as well when the new missile was coupled with better detection and tracking equipment. The SM-2 first deployed on board Wainwright (CG 28, ex DLG 28) in 1976. There were two novel features of the Mk 26 launcher, its fault isolating equipment and modular design. The former reduced maintenance down-time. The modular design of the system allowed the entire launcher with its vertical rotating carousel with missiles to be "plugged in" to the ship. The base of the module rested on prepared foundations within the ship. Once lowered in, the system needed only electrical and utility connections. The effectiveness of the Standard missile was enhanced by the Mk 26 launcher.
Even in the worst sea conditions that could cause heavy pitch and roll, the launcher could fire in rapid succession several kinds of missiles that included variants of the Standard missile, Harpoon, and ASROC A jettison device was fitted to shove any dud missile overboard.
One influence in the CGN 38 cruisers was the DX/DXG Program that used a Concept Formulation/Contract Definition procurement strategy for the acquisition of surface combatants. This latter program resulted in the DX, which became the DD 963 Class ships.
The "High End" of the DX Program was envisioned as a nuclear powered DXG, the DXGN, later, CGN. The successful development of the Mk 26 guided missile launching system and the promise of early availability of the long awaited Advanced Surface Missile System (ASMS, later to be called AEGIS) led to the decision that a design based upon the as-yet-unbuilt DLGN 36 Class would fulfill the DXGN unit's role.
Nuclear propulsion for naval striking forces had been studied several times. In 1966 all five congressional committees — the two armed services committees, the two appropriations committees, and the joint committee — concluded that the navy should have nuclear escorts for nuclear carriers. Congress might well be affronted if, after all the navy's experience with nuclear propulsion, it did not have the military knowledge to know whether it should support all-nuclear escorts for nuclear attack carriers, or, for that matter, if the navy had to tell Congress that more studies were necessary before taking a position.
On 3 February 1967 Rickover forwarded to Paul H. Nitze, secretary of the navy since 29 November 1963, a study that Naval Reactors had just completed. It compared two reactor escorts with gas turbines, each having the same armament. The study showed that an all-nuclear carrier task group built around the improved capabilities of the Nimitz was superior to those reported to the secretary of defense in any previous study. In an all-nuclear task group all the tank capacity of the carrier could be allocated to aircraft fuel. It was the supply of aircraft ordnance and aircraft fuel that would determine the need for replenishment. He recommended that the navy adopt the policy of providing nuclear carriers with all-nuclear escorts.
One paragraph in particular summed up a major part of Rickover's argument. "No matter how many tradeoffs we study of other ways to spend the money we need to pay for nuclear propulsion, we will always be faced with comparing unlike things; none of the tradeoffs accord freedom from logistic support for propulsion fuel which is provided by nuclear propulsion. The other tradeoffs provide additional defense protection to the CVAN, but none of them increase the offensive capability of the CVAN as well—as does nuclear propulsion in the escorts. To compare a larger number of conventional escorts with a smaller number of nuclear escorts at equal cost is not to compare alternate ways of achieving the same capability; it is merely to compare two different capabilities that can be achieved with the same amount of money."
The House committee changed the two gas-turbine ships to nuclear frigates by authorizing the remaining funds for the South Carolina and full funds for a second frigate (the Virginia, DLGN 38). While granting funds to study the DX/DXG ships, the committee barred their use in the design of any major fleet escort that was not nuclear powered.
Accordingly, the preliminary design of the CGN 38 (then called DLGN 38) commenced in late 1968. The resulting ship was approximately 20 feet shorter than its predecessor but some 3 feet wider. The full load displacement was about 200 tons more than the earlier design with very nearly the same draft, but increased trim aft. Due to unavailability of the ASMS, the missiles in the Mk 26 launchers were controlled by two Tartar D missile fire control systems fore and aft. The helicopter facility was to consist of a landing area with refueling capability but without any hangar.
During contract design some further modifications were made with the ASMS (later to be called AEGIS) included as a space and weight option. An intensive effort was made to reduce the displacement to less than 10,000 tons. Important at this point of development was the inclusion of the SH-2 LAMPS helicopter. There was some unassigned space in the stern and it was decided that this could be used as a below-deck hangar to house the helicopters plus the associated magazines, stowage, and ammunition. The concept was based upon the seaplane hangar arrangements used in the Baltimore (CA 68) class and later cruisers. The helicopter would land on the raised elevator platform; with the platform lowered the hangar would be enclosed by sliding doors or hatches.
In concept it seemed to be an excellent one, but in practice it proved to be unsuccessful. The seals to the hatches enclosing the helicopter hangar leaked seawater onto the hangar area below onto the helicopters, necessitating extensive freshwater washdowns. There were also problems with the elevators. The helicopter facility was later removed and Tomahawk box launchers were installed on the main deck where the elevator platform had been. These launchers were mounted in armored box launchers at the transom with control spaces located below in the old hangar complex. Earlier proposals to provide a VLS launcher for the Tomahawk missiles in place of the hangar were dropped.
The CGN 38 class had a distinctive bow anchor arrangement unlike their predecessors. Because of bow trim problems in early contract design, the keel-stowed anchor was eliminated and replaced with a bow-stowed anchor and an on-deck stowed lightweight anchor, based on German World War II experience with their battleships and battle cruisers. The bow flare was increased slightly to allow these anchors to clear the AN/SQS 53A bow sonar dome and improve dryness of the foredeck area.
These guided-missile cruisers were the last nuclear-powered surface combatants, other than the nuclear carriers of the Nimitz (CVN 68) class. Four ships were completed although the last two were completed much later than their earlier sisters due to substantial cost increases of $140 million. The fifth ship, which would have featured the AEGIS weapons system was canceled as the result of costs and the emergence of a new "Strike Cruiser" (CSGN) concept.
Three of the ships were slated for nuclear refueling, starting in Fiscal 1994, and a study was made in 1989 to also upgrade these ships. As part of the refueling a complex overhaul was studied to have two 64-cell VLS launchers replace the Mk 26 launchers and the AEGIS SPY-1B radar complex would be installed. The cost of refueling and the changes in the weapons and electronics were prohibitive and it was decided to scrap all four vessels.
Planned Refueling Complex Overhauls were canceled in the early 1990s due to the expense of maintaining the nuclear propulsion components, and the ships were all decommissioned after a relatively brief period of service averageing somewhat less than two decades. Thus the CGN-41 was commissioned in 1980 with a life expectancy of 38 years, though it was retired in 1997 after only half that period in service.
In fiscal year 1993, the Navy decided to decommission the newest class of nuclear-powered surface combatants instead of refueling them. These ships are being inactivated after an average of 17 years of service and with nearly half of their planned service life remaining. The decision was based on two factors-the need to reduce force structure in order to recapitalize the force and the ships' need for expensive nuclear refueling overhauls. Faced with declining budgets and large fiscal requirements, the Navy determined that the midlife modernization and upgrading through a refueling complex overhaul were not cost-effective. Even though there would be a near-term inactivation cost, the Navy would not incur the expense of a more costly refueling complex overhaul.
Moreover, the decision would provide an opportunity to divest a large surface nuclear infrastructure supporting a small ship population. Another rationale for the decision to decommission the nuclear-powered surface combatant force was that a decision to invest in a refueling complex overhaul would drive retention of this force for the next 20 years. Operationally, the nuclear-powered surface combatants are expensive, and they are maintenance and infrastructure intensive ships. Personnel, training, maintenance, and other supporting infrastructure costs were more expensive than their modernized, conventionally powered counterparts.
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