As the price of oil skyrocketed in 2008, some in Congress argued that it was pointless to keep building oil-powered warships. Surely the future lay with a return to the vision of the 1960s, when it seemed that nuclear power would soon dominate. A congressionally mandated study by the Congressional Research Service concluded that once oil was $70 per barrel, “the total life-cycle costs of a nuclear-powered medium-size surface combatant would equal that of a conventionally powered medium-size surface combatant.” It seems likely that the future cruiser, (CG[X]), at one time seen as a variant of the Zumwalt-class destroyer, will be nuclear powered. Therefore it appears to be a good time to take stock of the current nuclear program, to ask what has changed since the rush toward nuclear power stopped in the 1970s, and also to look at foreign nuclear-powered surface warships.
Excluding carriers, the Navy commissioned nine nuclear surface ships between 1961 and 1980.
In the late 1950s, it was assumed by some observers that at some point the U.S. Navy would build only nuclear warships. About 1955, the Bureau of Ships (the ancestor of the current Naval Sea Systems Command [NAVSEA]) produced a booklet of futuristic surface combatants, down to the level of frigates (then called destroyer escorts), all of them nuclear. The nuclear power organization within the bureau developed a range of reactor designs, including ones suitable for a cruiser (Long Beach) and, what was considered remarkable at the time, a large destroyer (Bainbridge), as well as for the carrier Enterprise. Excluding carriers, the Navy commissioned nine nuclear surface ships between 1961 and 1980. Long Beach (CGN 9), Bainbridge (CGN 25), and Truxtun (CGN 35) were each unique, the only ships of their class. These were followed by the two cruisers of the California class – California (CGN 36) and South Carolina (CGN 37) – and the four cruisers of the Virginia class – Virginia (CGN 38), Texas (CGN 39), Mississippi (CGN 40), and Arkansas (CGN 41). All of these ships were attractive because they could operate at maximum speed on a sustained basis. They were no faster than conventionally powered ships, but a ship using oil fuel cannot maintain high speed for very long. Particularly before the Soviets had nuclear submarines, speed itself offered considerable immunity to submarine attack. Even after the Soviets had submarines as fast as U.S. aircraft carriers, they could not hope to intercept such fast ships unless they were already trailing them, or they were cued by the Soviets’ complex ocean surveillance system. The latter was graphically demonstrated in 1968 when a Soviet November-class submarine intercepted USS Enterprise en route to Vietnam.
Current naval views of nuclear propulsion are inevitably colored by the way in which Adm. Hyman G. Rickover, for decades the chief of the program, handled it – and, more importantly, nuclear personnel. Rickover had a keen sense of the tactical and strategic potential of nuclear power. In effect he created a separate nuclear machinery organization outside the Bureau of Ships and its successor. His experience with conventional machinery convinced him that the nuclear innovation would succeed only if nuclear power was perceived as absolutely reliable. To that end, he insisted on intense training for all reactor operators (and all officers of nuclear ships had to be qualified operators). He rejected automation, the result being that nuclear engine rooms needed unusually large numbers of personnel who also were much more expensive than the average. Personnel made nuclear ships more expensive than might have been imagined. So did extremely strict standards for construction – which Rickover pointed out were the inevitable cost of the attractive new technology.
The pressurized-water reactors Rickover developed were inherently stable, hence safe. They operated at relatively low-steam conditions, which meant that the turbines they drove were considerably larger than those of contemporary fossil-fuel steam plants. Nuclear ships were larger than their non-nuclear counterparts. That was not always a bad thing. For example, nuclear carriers had large spaces, which were normally filled with fuel for escorts and for their aircraft. It does suggest that future nuclear ships will again be larger than their non-nuclear counterparts. That difference may be accentuated because current gas turbines are more compact than their steam predecessors – and they need far fewer personnel.
In the past, one attraction of nuclear power for surface ships was, first, that they needed much less support in the form of tankers. Although the Navy currently relies on unarmed tankers, that is only because it expects danger areas to be very localized, so that its ships can fuel in safety. In a harsher world, there would be no safe places. Tankers would have to be escorted, because they would always be at risk. Even now it can be argued that fueling is dangerous: USS Cole was attacked when she entered Aden to fuel. The example is probably misleading, because Cole was in Aden more to show the flag, but it will probably often be cited. If the future Navy is going to be severely limited in numbers, anything that provides more teeth for less tail may be appreciated – the question will be whether the higher cost of nuclear warships will cut teeth even more severely.
It can also be argued that the fewer ships that are needed to support any one ship, the more difficult it will be for an enemy to be sure that a particular ship spotted by radar or satellite is actually a warship, or at least a U.S. warship. Thus limiting or eliminating support for future warships might be valued as a way of making them more survivable. Formations of ships are certainly more recognizable than individual units.
A second attraction is the ability to deploy at high sustained speed. Ships normally steam at well below their maximum speed because they have to limit fuel consumption. One reason nuclear submarines seem so valuable is that, unlike surface warships, they can move at maximum speed to distant places (they can also take advantage of not being subject to weather). For submarines, this is a new advantage, because in the past, submarines generally deployed at low speed to remain silent. With no major foreign power listening in most places, that no longer matters. The strategic mobility now associated with submarines may make nuclear surface combatants attractive.