NAVY AIRCRAFT CARRIERS  - GAO/NSIAD-98-1 - August 1998 NAVY AIRCRAFT CARRIERS
Cost-Effectiveness of Conventionally and Nuclear-Powered Aircraft Carriers
GAO/NSIAD-98-1 -- August 1998

CONVENTIONALLY VERSUS NUCLEAR-POWERED COST-EFFECTIVENESS DEBATE--THE RATIONALE FOR NUCLEAR POWER ========================================================== Appendix II For fiscal year 1963, DOD requested a conventionally powered carrier. A prolonged debate to change the propulsion of the carrier, later named the U.S.S. John F. Kennedy (CV-67), to nuclear power, followed. The campaign to support nuclear power was led by the Chairman of the Joint Committee on Atomic Energy, the Secretary of the Navy, and the Chief of Naval Operations. Opposition to nuclear-powered carriers eventually weakened, and all aircraft carriers since have been nuclear-powered, beginning with the U.S.S. Nimitz (CVN-68) in the fiscal year 1967 program. Including the U.S.S. Enterprise (CVN-65), a total of eight nuclear-powered carriers have been built and two more are under construction.\1 In an April 1963 memorandum to the Secretary of Defense, the Secretary of the Navy concluded that ╣nuclear propulsion permits a significant increase in the beneficial military results for a given expenditure and that we must exploit and take maximum advantage of it. . .and that all new major warships should be nuclear-powered.║ The Navy staff's comparative analyses showed that the costs of a nuclear task force would be about the same as a nonnuclear task force with its fuel replenishment and escort ships. The advantages of nuclear propulsion in surface warships were summarized in an enclosure to the memorandum: "As a nation with an overseas strategy, nuclear propulsion in our combatant surface ships adds an essential new dimension to their versatility and effectiveness in war or deterrence of war. Increased range and staying power, plus a reduction in vulnerability provided by nuclear propulsion, will make naval forces much stronger and more useful as instruments of national policy and power." The specific advantages accruing to nuclear propulsion, according to the Navy study, were -- virtually unlimited high-speed endurance; -- optimized prepositioning of (nuclear) fuel (the reactor cores reduce the quantity and total costs of conventional fuel which must be prepositioned and protected); -- reduced vulnerability to atomic fallout because nuclear-powered ships do not depend on a constant intake of large amounts of air for boilers; -- increased shipboard electric power for new radars, sonars, and missile systems that would otherwise reduce the operating range of conventionally powered ships; and -- elimination of stack gases. In the language of the memorandum the meaning of "virtually unlimited high-speed endurance" was elaborated -- Nuclear-powered forces can be sent at high sustained speeds to distant areas of operations and arrive ready to go into action--they do not have to refuel before engaging the enemy. -- Independent operations of nuclear ships can be conducted in those areas where simultaneous deployment of the usual replenishment forces may require an unacceptable amount of time or risk. The necessary logistic support ships can start later and/or transit more slowly and still arrive in time for replenishment of aviation fuel and ammunition. -- The requirement of oil-fueled forces to take into account the risk of loss of fuel oil facilities either at the source or en route to the refueling rendezvous is eliminated. -- Absence from the restrictions imposed by fueling requirements significantly reduces the vulnerability of the force by eliminating the requirement to slow down to conserve fuel and to refuel. These required refuelings reduce the tempo of any offensive and defensive effort. -- The nuclear-powered forces require less overall replenishment and have much greater freedom in the selection of location and time for the replenishment rendezvous. Nuclear propulsion also reduces the size of the logistic support force and its escorts. -- Nuclear-powered ships can be kept in an area of minimum vulnerability with respect to the enemy submarine threat until required to move into another action area. They can proceed at a high sustained speed using such indirect routes and circumvention to increase enemy submarine tasks as may be indicated by the overall tactical situation. The Defense Secretary's February 1963 memorandum also asked the Navy to comment on specific topics. The Navy's comments regarding worldwide deployments, underway replenishments, future shipbuilding programs, and force structure reductions are summarized below. -- Worldwide Deployments Nuclear propulsion will greatly facilitate fast initial reaction, rapid transit, readiness for combat on arrival, and strike group operations with reduced task group vulnerability and logistic support requirements. The improved efficiency of coverage of potential trouble areas associated with nuclear-powered task groups can be capitalized on by either (1) better coverage, using the same numbers of groups as with conventional forces or (2) comparable coverage, using fewer groups. The potential exists to compensate for the increased costs of individual nuclear-powered ships by obtaining more effectiveness or by reducing force levels as these nuclear ships are delivered to the fleet. As they are delivered to the fleet, the nuclear-powered ships will be phased into those assignments where transit distances may be long and logistic support somewhat limited. For example, a nuclear-powered task group could perform a high speed transit of about 5,000 miles from 10 to 50 percent faster than a conventionally powered group, depending upon the level of fuel support received by the conventionally powered carrier groups. The costs of achieving this capability with a nuclear force would be approximately the same as with a nonnuclear force with its fuel replenishment and escort ships. -- Replenishment Underway replenishment is the most reliable and effective method of restocking naval forces with large quantities of consumables in combat or in peacetime deployment to remote areas. This kind of support, however, cannot be relied on in armed conflict situations or in areas characterized by inadequate or nonexistent bases. By eliminating the requirement for ship propulsion fuel, requirements for replenishment of aviation fuel and ordnance will become the controlling factors, varying directly with the level of aircraft activity and/or combat operations. Design and operational evaluations will continue to be directed toward minimizing dependence on nuclear-powered ships upon logistic support by increasing consumables storage, such as was done in the case of the CVAN-67 design for aviation fuel and ordnance. -- Future shipbuilding programs The application of nuclear propulsion is toward a goal of all nuclear attack carrier groups. The greatest advantages of nuclear power accrue when the entire task group is so equipped. However, the advantages to screen ships themselves are significant. An alternative would be to use a nuclear-powered carrier with a conventional screen; however, in this case, the operational and logistics gains will be less if the nuclear-powered carrier must function as a part-time oiler and is still tied to the logistics of her escorts. -- Force reductions Nuclear-powered task groups will provide improved efficiency of coverage of potential trouble areas. The benefits thereby can be capitalized on, in part, by a reduction in carrier task groups or by increased effectiveness. A general transition to nuclear propulsion should permit some reduction in total numbers of ships required to meet the Navy's widespread, worldwide commitments. -------------------- \1 The Harry S. Truman was commissioned in July 1998.