Compared to the alternatives, a large-deck carrier will give the nation more flexibility and growth potential to meet a variety of 21st-century challenges.
In June 2000, the Defense Acquisition Board approved the Navy's plan to develop a new class of large-deck nuclear-powered aircraft carriers, known as CVNX.
The first ship will incorporate a new propulsion plant with greater electrical generating capacity (to enable electric auxiliaries and electromagnetic catapults and possibly future electromagnetic weapons) and will cut manning through reduced workload and selected automation. Plans for CVNX-2 include new survivability features and a somewhat larger and rearranged flight deck for greater sortie generation and reduced flight-deck workload.
Though the board's approval occurred after a four-year formal Analysis of Alternatives (AoA) plus three high-level reviews by the Office of the Secretary of Defense, debate about CVNX is unlikely to go away because the choices in this program will shape the carrier force for decades to come. In fact, it appears that potential changes to the carrier program are being considered as part of the new administration's broader defense review. In effect, they are asking once again: What kind of carrier makes sense for the 21st century? In light of military-technical trends, are big nuclear-powered carriers still the answer?
There are many different ideas on alternative courses: small carriers with short takeoff/vertical landing (STOVL) aircraft; mid-size carriers; large mobile offshore bases; even cutting the carrier force and manned aircraft in favor of more unmanned systems dispersed over the fleet. These alternatives and others were examined during the CVX AoA, but after many detailed calculations involving a number of variables and assumptions, the Defense Acquisition Board's consensus is that large-deck carriers remain the correct choice for the future.
Mid-size Carriers: A Modern Midway?
The least radical of the alternatives would be for the Navy to build a new class of mid-size carriers similar to the Midway (CV-41). The Navy operated mid-size carriers of this class into the 1990s; in fact, the Midway was one of six carriers that participated in Operation Desert Storm, capping more than 40 years of service. Why not build a modern version?
This issue involves not only carrier size but also nuclear versus conventional propulsion. The AoA found that nuclear power adds roughly 10% to the life-cycle cost of a carrier regardless of its size. The advantages of nuclear power were analyzed and debated in the AoA, and the Defense Acquisition Board endorsed the Navy's conclusion that they were well worth the additional cost. Here, however, I focus on the size and air-wing capacity of the ship.
The AoA cost and design work showed that propulsion and size issues can be separated for ships in the size regime under consideration (40-80 aircraft wings). The key finding about large versus mid-size carriers was that large decks realize considerable economies of scale, in terms of both cost and sortie generation. The results are illustrated in Table 1.
Mid-size carriers are a little cheaper but provide a lot less combat power. The savings for a 55-plane carrier, compared to the cost of a comparable 75-plane carrier, would be roughly 8% for both total life-cycle and initial construction costs. (The figure rises to 13% if the cost of aircraft is included.) Now, given the billion-dollar sums involved this represents a lot of money, but for that 8% additional cost, aircraft capacity can be increased from 55 to 75, or 36%—more than three times the percentage cost increase. This is what economists call economies of scale.
There is an analogous return in operational capability. Larger decks can generate more sorties and devote the additional sorties to strike. Over the course of a campaign, a new 75-plane CVX force can generate roughly twice the number of strike sorties as the same number of 55-plane carriers. These data indicate that modest increases in cost lead to large gains in effectiveness.
Can the Navy afford enough aircraft to exploit the potential of large carriers? The answer will depend on whether the service can sustain current funding for carrier-based aircraft and whether the Joint Strike Fighter comes close to meeting its cost goals. If not, the Navy will have to deploy Marine squadrons on carriers or deploy with slightly less than capacity.
But even if budgetary pressures prevent the Navy from buying an aircraft for every carrier spot, the larger deck space of a 75-plane carrier still is very valuable. For example, because of its larger flight deck and greater fuel and ordnance capacities, a 75-plane carrier with 55 aircraft can generate 40% more strike sorties than a 55-plane carrier. The Navy also could augment the carrier in times of crisis. In addition, aircraft force levels can be changed fairly rapidly; increasing carrier deck capacity takes decades. The bottom line is that the economies of scale in both cost and strike potential strongly favor large-deck carriers over mid-size carriers.
Small Carriers
Some people propose more radical alternatives involving a combination of small carriers and other systems, such as land-based air, missile ships, and even large mobile offshore bases. Many of these alternatives have been examined several times in the past 20 years. The issue is whether new technologies and changing international conditions might lead to a different answer this time. Here's what the Analysis of Alternatives found:
- One small carrier doesn't carry enough aircraft. A 40-plane carrier would accommodate about 25 aircraft on the flight deck for operations. About half of these would be needed for various surveillance operations, electronic countermeasures support, tanking, and spares—leaving only about 12 for strike, air defense, and other operations. This is simply not enough. For example, even a modest battle-space dominance posture to counter air and surface threats typically would involve 12-14 fighter-attack aircraft, leaving none for strike, and the CVX Mission Need Statement calls for CVX to conduct simultaneous strike and battle-space dominance operations. A single small carrier does not carry nearly enough aircraft to meet this fundamental criterion. But what about two small carriers or a small carrier supplemented by other systems?
- Two small carriers could do the job but would cost too much. Much of the work on small carriers in the CVX AoA involved possible ways to make up for the deficiencies of a single small carrier. Could the Navy buy and operate two small carriers for the same cost as one large CVX? The answer is no. A 75- to 80-plane CVX costs less than two-thirds as much to buy and operate as two comparable 40-plane CVXs.
- Other options exist, but none work in every important case. Conceivably, DoD could rely on other forces and systems to supplement the small carrier in cases where its air-wing capacity is insufficient. The ideas fall into two main categories: the small-capacity CVX offloads surveillance and battle-space dominance tasks to other assets in the battle group or to aircraft based ashore or on some kind of mobile offshore base; or the striking power of the carrier's small air wing is supplemented with either land-attack missiles or land-based aircraft. Though these approaches might work in some circumstances, each has major problems in some key circumstances.
Land-based aircraft are capable but not always available. Once on scene, they can provide the capability of sea-based aircraft, but history demonstrates that bases are not always available when and where needed. One idea for overcoming the base-access problem is a mobile offshore base, a mile-long semisubmersible structure ten times the size of deep-sea oil drilling platforms. DoD is considering this concept for logistics applications, but the technical and economic feasibility have not been determined, and the idea is less suited to tactical applications that would expose the structure to enemy threats.
Missiles have an important role but are too expensive to replace aircraft for sustained strike. Tomahawk and the conventional air-launched cruise missiles have demonstrated their value in contingency strikes, and their role is likely to grow as more capable variants enter the force. But million-dollar missiles are less suited to the "heavy lifting" of a sustained strike campaign. For example, with the precision-guided weapons now entering the inventory, a single carrier air wing can deliver the strike potential of 4,000-5,000 Tomahawks over a 30-day campaign. Replacing a significant portion of tactical aviation strike potential with missiles would require expansion of the missile force from a few thousand to tens of thousands, plus more ships to carry the additional missiles—which would cost more than comparable aircraft strike potential. Aircraft also provide greater operational flexibility, particularly for striking battlefield targets.
- STOVL and small carriers are different issues. Short-takeoff and vertical landing strike fighters under development in the Joint Strike Fighter program will likely operate from carriers on some occasions, and might eventually prove desirable for regular carrier application, but this would not change the argument against small decks for the Navy. For example, proponents of STOVL often argue that it would provide more flexible launch and recovery operations on a carrier. This depends on the STOVL characteristics, but the AoA showed that if realized, the advantages would be more important for large carriers that have many aircraft on deck. Conversely, the AoA showed that STOVL aircraft are not needed for an efficient 40plane carrier design. In sum, STOVL aircraft and carrier size are separate issues. STOVL aircraft make sense for the Marine Corps and perhaps eventually for the Navy. Small carriers don't make sense for the Navy, even with STOVL aircraft.
More Radical Approaches
Some observers foresee a true revolution in military affairs (RMA) and argue for a radical restructuring of U.S. military strategy, forces, and investment priorities, with much greater emphasis on unmanned systems. These people tend to see carriers and manned aircraft in general as "sunset systems" whose time will soon pass and whose funding could be diverted to RMA technologies, such as unmanned aerial vehicles and land-attack missiles.
The current DoD approach to unmanned systems is one of evolution. In fact, the Navy has been in the forefront of this trend, pioneering conventional land-attack cruise missiles. Current Navy plans call for roughly double the number of Tomahawk missiles in the fleet over the next 15 years and for development of advanced guns with long-range precision-guided projectiles and fast-strike missiles to provide greater battlefield fire support. In short, the Navy is embarked on an evolutionary transformation in which unmanned strike systems will play an ever increasing role. At the same time, the Navy (and Air Force) is increasing the strike potential of manned aircraft with more capable aircraft and new precision-guided weapons, and plans to maintain a core force of manned aircraft for decades to come.
RMA proponents call for revolution not evolution. They propose a more rapid and radical shift to unmanned strike systems. They see new technologies as both leading to a new generation of unmanned systems with greater effectiveness and lower cost, and working to the disadvantage of manned aircraft by enabling regional opponents to threaten both aircraft and their bases. These claims involve a variety of technical, economic, and operational factors, most of which are arguable and difficult to resolve, but some general observations are appropriate.
First, let's admit that concerns about future anti-access threats in general and threats to carriers and airfields in particular are valid. The existing very low threat levels are likely to increase. Potential regional opponents have clear incentives to look for new ways to counter U.S. power-projection capabilities, and new technologies will offer new approaches. But this does not imply that carriers will become vulnerable or that the fleet will be unable to respond. History has shown that translating technical capabilities into operational threats is not a trivial feat. Though antiship missiles have been available for two decades, the historical record for successful attacks is very limited, and a significant fraction of the victims were either defenseless or unalerted.
In addition, technology is not a one-way street; it can help the fleet, too. For example, the greater range and payload of the F/A-18E/F and Joint Strike Fighter will enable a future air wing to deliver more strike payload from 450 nautical miles than an F/A-18C wing can deliver at 250 nautical miles today. This ability to conduct initial high-intensity strikes from standoff ranges provides time and battlespace to counter initial enemy attacks, reduce enemy forces, and shape the battlespace—reducing the threat and lowering the risks of coming in closer. Undoubtedly the fleet will be exposed to some threats in these types of operations, and there will be some risk of taking a few hits. That is the nature of war—and the rationale for improved survivability features and damage control in newer carriers. In sum, the likelihood of increasing threats is a cause for continuing vigilance, but it is not by itself a reason for a radical restructuring of the force.
Second, let's look at affordability, a continuing concern as the Navy struggles to recapitalize the fleet with new ships and aircraft. The high cost of buying and operating carriers and their aircraft only makes this problem harder. RMA proponents argue that unmanned systems offer a way out of the current resource bind because unmanned systems will be much more affordable to buy and operate than manned systems.
The current economic facts are that missiles are cheaper than aircraft but more expensive than bombs. This means missiles on existing ships are economical for smaller strikes but aircraft are more cost-effective for sustained strike campaigns. For example, based on sortie rates in recent exercises, an air wing with 50 fighter-attack aircraft could deliver 5,000 weapons (roughly the number that could be carried by a carrier and a fast combat support ship) in about 30 flight days of sustained high-intensity operations. Occasional stand-down days would be required for safety and logistics reasons, which would stretch out the delivery somewhat. On the other hand, the larger strike payloads possible with the F/A-18E/F and Joint Strike Fighter could speed payload delivery somewhat. Replacing this firepower with missiles would require thousands of additional missiles plus ships to carry them, which would cost as much as or more than the carrier and its aircraft.
Some will counter that technology will alter the current cost structure drastically (as it has in the computer industry), reducing the cost of unmanned systems but not helping manned aircraft nearly as much. Despite such predictions, these types of dramatic cost reductions have yet to appear in major military systems.
Others will argue that precision strike technology and targeting intelligence will be so good in the future that much less firepower will be needed—so that the sustained firepower potential represented by aircraft will not be essential. For example, after the Gulf War the Center for Naval Analyses estimated that greater availability of precision-guided munitions would have enabled the coalition to achieve the same level of target destruction in roughly half the number of sorties flown in the war. RMA proponents see even greater effects in the future. However, these visions reflect considerable faith in strategic bombing and discount battlefield strike support to ground operations.
Visions and Prudence: What's the Right Balance?
After all the debates are over, the issue often comes down to the role of new visions in setting the course for the future. RMA proponents cast themselves as the visionaries. They tend to see the Navy (and other services) as locked in the past—like the battleship admirals in the 1920s and 1930s, who were reluctant to embrace the ongoing revolution in air power.
The Navy, on the other hand, sees itself as prudent, embracing an evolutionary transformation but not compromising proven core capabilities such as tactical aviation and carrier forces until the uncertainties in RMA technologies and their ultimate costs are worked out. Some visions do come true—naval aviation itself, for example—but the number of visionaries is far larger than the number of successful visions. An all-nuclear Navy, 100-knot ships, and cheap lethal loitering drones are just a few visions that foundered on technical and economic factors.
We cannot know whether today's choice for the carrier force will be the optimum for 40 years from now. But a new large carrier that has flexibility and growth potential will be a valuable resource for a wide range of circumstances. Its large flight deck and electromagnetic launch system will accommodate a variety of joint aviation systems, including conventional and STOVL aircraft, unmanned aerial and combat air vehicles, and precision-guided weapons delivered by aircraft. (Though not currently planned, a large carrier also could include launchers for a substantial number of land-attack missiles.)
The revolutionary potential of RMA technologies certainly merits pursuing their development, but to justify the risks inherent in the radical shift advocated by some RMA proponents, one must believe either that the U.S. Navy will be in dire straits in the near future or that the advertised economic and warfighting benefits of the radical changes are nearly certain. These propositions are possible, certainly, but both are highly arguable. In view of the uncertain pace and outcome of the ongoing revolution in military affairs, prudence argues for maintaining the core capabilities of the current force, including the carrier force. In addition, a new large carrier with flexibility and growth potential provides capabilities that will be valuable even if the full RMA vision does come true.
Dr. Perin works at the Center for Naval Analyses. From 1996 to 1999, he served as director of the CVX Analysis of Alternatives, which involved a variety of Navy organizations. He currently is directing the AoA for JCC(X), the Navy’s proposed new command ship.