Crying Wolf: The Navy Does Not Need More Subs

The Navy is once again campaigning for more attack submarines, and Congress seems more than willing to acquiesce. The Navy has already persuaded the secretary of defense to increase the submarine goal from the 50 boats in the 1997 Quadrennial Defense Review to 55 (curiously, about the same number the Navy currently possesses in what has been a declining force). But the Pentagon may want even more boats.

On the basis of rising requirements for intelligence collection, a Pentagon study cited a need for 55 to 68 submarines by 2015 and 62 to 76 vessels by 2025. Conveniently, of course, the rationale for those requirements is highly classified. However, it seems strange that intelligence collection requirements are now increasing after an important target for such collection — the Soviet Navy — collapsed over a decade ago. If the rationale for increasing intelligence requirements is suspect, the Navy’s uncanny ability to predict such needs 15 to 25 years into the future seems even more incredible — especially when future threats are uncertain. No one can know whether a near-peer competitor — for example, a rapidly expanding Chinese navy or a resurgent Russian fleet — will arise during that 25-year period.

Yet Congress seems unperturbed by those inconsistencies and uncertainties. In their Fiscal Year 2001 Defense Authorization bills, both of the Armed Services Committees included provisions allowing the Navy to procure five additional Virginia-Class attack submarines in future budgets. Even assuming that the Navy’s dubious future intelligence collection requirements are valid, does the United States need more submarines? Is another alternative available?

The Navy should consider using two or more rotating crews on each attack submarine. A crew’s schedule is the main factor that makes submarine deployments very inefficient. According to the Navy, about 4.5 submarines are needed in the force to keep one deployed on station overseas. When not deployed, the crew needs time to train (both operationally and in the classroom), to help maintain the ship and to enjoy a well-deserved rest ashore. The overwhelming majority of a crew’s time is spent in a nondeployed status.

Despite the Navy’s refusal to consider rotating crews on attack submarines, the service uses blue and gold crews on each of the Trident submarines that carry nuclear ballistic missiles. The Navy made the vague claim that using dual crews was possible on ballistic missile submarines because those vessels — compared with other ships — have fairly regular deployments. The implication was that other types of ships and submarines might need to be “surged” to respond to unexpected peacetime deployments. In a post-Cold War world, however, an attack submarine force — with the primary peacetime mission of spying off the coast of potentially hostile states — should have much more predictable deployments.

Another of the Navy’s objections to rotating crews is that more frequent use of existing attack submarines will lessen the life of the vessels by depleting their nuclear reactor cores faster. According to Rear Adm. Malcolm Fages, director of the Navy’s Submarine Warfare Division, operating attack submarines with dual crews would shorten the vessels’ expected lives from 30 years to 24 or 25 years.

Despite a slightly shorter life expectancy, a simple calculation shows that efficiencies could still be achieved by operating submarines with rotating crews. The annual acquisition cost of a Virginia-Class submarine is roughly $60 million ($1.8 billion average acquisition cost per submarine divided by an expected 30-year life for the boat). The annual operations and support costs for an attack submarine are about $47 million (that number includes a slice of the shore infrastructure). Thus, the total annual cost to acquire, operate and support an attack submarine is $107 million. If a second crew were added, the annual acquisition cost would rise to $75 million a year ($1.8 billion per submarine divided by the shortened expected life of 24 years) and the annual operations and support costs would double to $94 million per year (erring on the high side because a significant portion of the infrastructure is not for the crew, but is associated with using nuclear propulsion). Thus, the total cost of acquiring, operating and supporting an attack submarine would rise to $169 million per year.

However, despite the increase in the total cost per submarine, overall savings would result from being able to conduct the same number of intelligence missions with half the number of boats. With dual crews, the need for 55 to 76 submarines would fall to 28 to 38 boats. So 55 submarines with single crews — costing $107 million per boat per year — would have a total annual cost of $5.9 billion. In contrast, 28 submarines with dual crews — costing $169 million each per year — would have a total annual cost of only $4.7 billion. Similarly, 76 submarines with single crews would cost $8.1 billion per year compared with only $6.4 billion annually for 38 boats with dual crews. The result of the calculation is corroborated by experience with the Trident fleet: faster depletion of reactor cores — with increased use — does not seem to nullify the advantages of using dual crews on those vessels.

Thus, even if the Navy’s dubious claims about increasing intelligence requirements are accepted, the submarine force does not need to be expanded. By improving the efficiency of submarines during peacetime, the existing submarine force would be more than adequate for intelligence collection. At the very least, the Navy should be required to try a pilot program for operating attack submarines with more than one crew.