In support of its mission to deter conflict or fight in wars if necessary, the Navy considers it a core responsibility to maintain a forward presence—to keep some of its fleet far from U.S. shores at all times in areas that are important to national interests. Toward that end, at any given time, about one-third of the fleet is deployed overseas. The rest of the Navy’s ships are in or near their home ports in the United States for maintenance, training, or sustainment (a period in which a ship is in port but ready to deploy quickly). Most of the ships that contribute to the Navy’s current forward presence of about 100 ships sail from ports in the United States; 31 others are now stationed permanently in foreign countries or at overseas U.S. military bases. In the future, the Navy expects to boost the proportion of ships that it bases abroad.
CBO estimates that, for the next 30 years, the Navy’s 2015 shipbuilding plan (which aims to increase the fleet from 281 ships in 2014 to 306 ships by 2022) would cost about $21 billion annually, on average, in constant 2014 dollars. The Navy’s estimates set the figure somewhat lower—at about $19 billion per year. Both estimates are greater than the annual average of almost $16 billion that the Navy has spent for the past three decades, which suggests that the Navy may have difficulty affording its plans. The Chief of Naval Operations’ emphasis on forward operations indicates that the Navy has committed to maintaining the largest possible forward presence under any given budget plan.
What Size Fleet Could the Navy Maintain With Smaller Shipbuilding Budgets?
CBO assessed the effects of three smaller annual shipbuilding budgets—
$16 billion, $14 billion, and $12 billion—for the next 30 years. In all three cases, by 2044, the fleet would be smaller than would be the case under the Navy’s current plan (click figure to expand):
- Under the $16 billion budget, by 2044, the fleet would consist of 251 ships, 17 percent fewer than under the Navy’s current plan;
- Under the $14 billion budget, it would be 230 ships, 24 percent fewer than under the current plan; and
- Under the $12 billion budget, it would be 208 ships, 31 percent fewer than under the current plan.
Those estimates reflect an assumption that the Navy would reduce the number of its major warships—aircraft carriers, surface combatants, submarines, and amphibious warfare ships—in rough proportion to their current share of the fleet.
How Could the Navy Maintain Its Forward Presence Under Smaller Shipbuilding Budgets?
The Navy could maximize its forward presence with smaller budgets by expanding the use of three methods that it currently applies to boost overseas operations:
- Deploying ships for longer periods,
- Basing more ships and their crews overseas, and
- Assigning more than one crew to some ships to permit longer deployments.
Even under smaller budgets, CBO found, the Navy could expand its use of each method to maintain the current forward presence, although all three involve costs and pose disadvantages. And even though the Navy might be able to maintain its forward presence by making more use of those methods, smaller fleets would nonetheless reduce the service’s ability to implement its war plans in the event of conflict and would limit its flexibility in a crisis short of war.
The Navy also could use different mixes of those methods to maintain its forward presence. To illustrate a range of possibilities, CBO analyzed two basic approaches: The first would simply lengthen many ships’ deployments; the second would combine the other two methods into a single approach to increase the efficiency of the ships’ use.
Approach 1: Deploy Ships for Longer Periods. Under this approach, the Navy’s ships would undertake more frequent and longer deployments. For example, with an annual shipbuilding budget of $16 billion, most large surface combatants (cruisers and destroyers) and aircraft carriers would be deployed for 10 months out of a 36-month operating cycle (or 28 percent of the time—the other 26 months would be devoted to maintenance, training, and sustainment); under a $14 billion budget, those ships would be deployed twice in a 36-month cycle, for 6 months each time (or 33 percent of the time); and under a $12 billion annual budget, the ships would be deployed twice in a 36-month cycle, but for 7 months each time (or 39 percent of the time). By comparison, in 2013, the Navy’s destroyers were deployed, on average, for a little longer than 7 months out of a 27-month operating cycle, or about 26 percent of the time.
Longer deployments are more expensive than shorter deployments but, under the scenarios considered in this report, longer deployments are less expensive than buying larger fleets. Costs increase for longer deployments because sailors are paid more while they are at sea, ships consume more fuel, and equipment must be replaced sooner because it wears out faster. But the additional operating costs of longer deployments would be considerably less than the savings that would result from the lower procurement costs and smaller operating budgets required to maintain smaller fleets. As a result, by CBO’s estimate, this approach would save between $11 billion and $17 billion per year, depending on the size of the fleet.
Several disadvantages, sometimes with accumulating effects, can arise from longer periods at sea. For example, if the ships must be deployed quickly because of a crisis or a war, crew members who have already been at sea for an extended time could be tired. Longer deployments subject sailors and families alike to added stress, which might hamper the Navy’s retention of crew members. Higher sea pay or larger retention bonuses might or might not mitigate that problem. If ships are away from home ports more often or for longer periods, maintenance schedules could be disrupted or altered; if that resulted in less effective or less timely maintenance, ships might not be able to remain in the fleet until the end of their expected service lives. Planning for longer deployments and increasing maintenance may mitigate that problem.
Approach 2: Base More Ships Overseas and Rotate Crews on More Ships. The second approach CBO examined would require the Navy to base another 14 to 18 ships—including aircraft carriers—overseas and to increase by between 12 and 22 (depending on the shipbuilding budget) the number of ships that used rotating crews. Basing more ships overseas can avert some challenges of longer deployments—crews are not as tired and are able to spend more time at home—and ships are more likely to be close to crisis spots. But this approach would save less than the first, mainly because of higher expenses for maintenance and personnel as a result of operating the ships more and using more crews. The increased spending could offset a substantial portion of the savings from smaller procurement and operating budgets, particularly at the lowest of the three budget amounts, but this approach could still save between $10 billion and $12 billion each year, depending on the size of the fleet.
Rotating crews pose several disadvantages, however. Their use on attack submarines, destroyers, and amphibious warfare ships could raise logistical and cultural challenges. In particular, the Navy would need to keep the crews that are not deployed trained and ready to go to sea when their turn arose to operate the ships. Crews might identify less with a particular ship—possibly resulting in lower-quality work or diminished attention to maintaining equipment in the best possible condition. The Navy has overcome such challenges in the past, notably in its staffing of ballistic missile submarines with a pair of crews alternating on fixed-period deployments. The Navy also uses rotating crews on its new littoral combat ships, but widespread application of dual and multiple crewing to other parts of the fleet would present a greater challenge.
Expanding the Navy’s forward presence by basing more ships abroad might reassure allies or deter potential adversaries, but it also could increase the fleet’s vulnerability to attack. For example, a larger concentration of naval forces based overseas would make the fleet more vulnerable to a surprise attack by another nation, by terrorists, or by other nonstate actors. And overseas bases can be closed off relatively quickly if a host government decides it no longer wants U.S. Navy ships based in its harbors. Finally, some challenges could be economic: With more ships based overseas, some areas in the United States near naval bases would see reduced economic activity (while the host countries might see more).