vide a more direct comparison of life of ship fuel consumption; another is the personnel factor in which an increase of 10 to 25 percent in costs will have a direct effect on overall personnel allocations; and, third, the effect on the maintenance funds in the S. & F. appropriation, where an increase of about one-third will have a very important impact since the current allocations of funds to maintenance is marginal even for conventional ships. The increases in cost, therefore, will affect shipbuilding appropriations, personnel appropriations and maintenance and operations appropriations.

S. Weight, space, and endurance

a. Nuclear propulsion plants for surface ships have been heavier and have required greater volume than the conventional plants they have replaced, neglecting the ship's endurance fuel. The inclusion of the ship's design endurance fuel makes these installations more comparable from the weight and volume basis; however, there still exists the difference of endurance. The nuclearpropelled ships currently have many times the endurance of their conventionally powered counterparts; longer life cores will increase this factor with resultant reductions in costs, and no changes to weight and volume.

b. The concentrated weights and larger machinery spaces for the nuclear propulsion plants have dictated different ship arrangements and have required new consideration in ship design. Utilization of the available reactor designs placed some restrictions on the shaft horsepower of the three prototype nuclear surface ships. Matching the endurance characteristics of the reactor plants with reliable steamplant components also has caused increases in weight, space, and cost. The net result is the three prototype surface ships have a maximum speed capability somewhat less than their conventional counterparts. The maximum sustained speeds are substantially similar.

c. The comparison of weights of machinery plants of conventional ships must include the fuel oil; and the amount in any ship design is a matter for decision that is determined by a suitable combination of operational performance, military characteristics, and costs.

d. The combined requirements of suitable weapons systems and electronic equipments with nuclear propulsion result in the larger DLG-16 type, being the minimum size ship in which a suitable two-reactor nuclear plant can be installed within the current state of nuclear technology. The use of the single reactor plant with the same power, now under development, will reduce the cost and weight of the nuclear propulsion plant and the ships of this class. The studies of the application of nuclear power to smaller ships has generally shown that very large proportional increases in costs, size, and displacements are required to maintain a balance in the combination.

e. The personnel requirements in nuclear propulsion plants at the present time are somewhat greater in numbers and require additional accommodations in ships.

4. Developments

a. The progress in development of nuclear reactor cores is highly encouraging for the future. The core life has increased severalfold from the first Nautilus core, and the AEC has indicated that they are working on longer life cores. Further, the costs of these cores are decreasing at the same time core life is being extended.

b. The Atomic Energy Commission has undertaken developments to design a single nuclear reactor plant of much higher horsepower than is currently available from any single naval propulsion reactor plant. This development will help reduce the cost of nuclear surface ships as a result of requiring a lesser number of reactors; and some reduction in the weight and size of the nuclear surface ships will result.

5. Provisions and supplies

a. The endurance of ships also involves their capacities for food, spare parts and consumable stores, and the requirement for these is expected to remain the same for either type of propulsion system. These categories of replenishment should, in practically all kinds of employment, be made sufficiently frequent to maintain the ships in an adequate degree of readiness. The requirements for ammunition and aviation fuel are similar, but the frequency of replenishment is dependent upon the nature of the operational employment and cannot be as readily predicted.

6. Benefits to different types of ships

The application to nuclear propulsion has potential advantages which can not be fully predicted until operational experience has been gained from a number of these ships. The following is a brief evaluation of some considerations regarding the application of nuclear power in frigates, cruisers, and carriers: a. Destroyers and frigates.—(1) These types now have the shortest endurance of the combat-ship types. The latter classes with longer endurance have increased considerably in size and cost to provide greater space and weight for larger weapons installations and additional fuel oil.

(2) The destroyer and frigate types require more frequent refueling since their steaming distances are usually greater than the larger ships. They do not usually require as frequent replenishment of ammunition and aviation fuel, so that the NSFO requirement remains the limiting consideration under practically all conditions.

(3) The requirements of the planned new equipments, such as sonars and radars, for greater amounts of electrical power will all require increased amounts of fuel to maintain their current endurance.

(4) These several considerations indicate that the frigate class of destroyers will derive the greater benefit from nuclear propulsion.

b. Cruisers.—(1) Cruisers already have moderate endurance, but historically cruisers have roamed over larger areas than the main task forces and are also available for independent operations so that long endurance would be an identifiable asset. The comments on impending new radar electrical power requirements in 6.a (3), above, are also applicable to cruisers.

c. Carriers.-(1) The CVA's have the greatest amount of endurance and fuel, and if they are released from the need to fuel escorting ships, their endurance would be increased. In the combat areas during sustained air strike operations, the critical requirements are aviation fuel and ammunition, rather than fuel oil. (2) Nuclear propulsion does not of itself offer the same degree of improvement of capabilities in CVA, although the larger CVA (N) carries slightly more aviation fuel. However, nuclear propulsion would increase the average speeds in oversea movements when weather and sea conditions could become the limiting factors; and if the requirement for CVA to refuel escorts were eliminated, the amount of aviation fuel could be increased which would result in longer periods of sustained air operations between ship and aviation fuel replenishment. 7. Construction and overhaul facilities

a. There are now two Naval shipyards (Portsmouth, N.H., and Mare Island) and five commercial yards (Electric Boat, New York Shipbuilding, Newport News Shipbuilding, Ingalls and Bethlehem-Quincy) that have facilities for constructing and overhauling nuclear-powered ships. Three additional naval shipyards (Norfolk, Charleston, and Pearl Harbor) are now scheduled to receive the facilities required for the overhaul of nuclear-powered ships.

b. When the nuclear surface fleet is expanded, additional facilities for construction and overhaul may be required beyond those now existing and planned; and may involve tenders for afloat support capabilities.

c. Nuclear-powered surface ships are designed to at least the same criteria for sustaining damage to the machinery spaces as conventional ships, and the reactors are located in the most protected areas of the ship. Repair of storm or collision damage would normally not be significantly more difficult than for similar damage on conventional ships. These nuclear-powered ships have those features required for safety included in their design to provide, to the maximum practicable extent, for all foreseeable contingencies which could arise from storm, collision, or battle damage.

PART II. FAVORABLE ASPECTS OF NUCLEAR PROPULSION IN SURFACE SHIPS

1. Virtually unlimited high-power endurance with the following advantages: a. Elimination of the time required and the operational limitations imposed by the refueling requirement for surface ship propulsion fuel.

b. Elimination of need for protecting combatant and replenishment ships during refueling and of the oilers proceeding to refueling rendezvous.

c. Elimination of replenishment oilers for that portion of the fleet having nuclear power.

d. Higher average speeds during transits to the area of operations.

2. The nonnuclear portions of the steam machinery plant, such as the turbines and their auxiliaries, are generally of simpler design since the requirement for high thermal efficiency is not as controlling as it is for conventional plants. Some of the nonpropulsion auxiliaries are also of simpler design. This can be expected to provide greater reliability and easier maintenance.

3. The immense reservoir of endurance in the nuclear reactor may have dis tinctly favorable potential for large ancillary power requirements in a ship, such as steam for catapults, and the very high electrical loads of new radars and

sonars.

4. A stockpile of reactor cores could be created in the strategic materials program. These stockpiles of reactor cores are not a radiation hazard; they require relatively small storage areas, and new individual cores are readily transportable to locations suitable for installation.

5. There is a greater probability of orders of magnitude improvement in the new field of nuclear power than in an older source, such as fuel oil, that has been subjected to generations of developments, refinements, and improvements. The decreasing costs of nuclear cores is one significant example which could have even greater significance if the cost of fuel oil continues to increase.

6. Stack gases are eliminated with nuclear propulsion. This eliminates the corrosive effect of these gases on radar antennas and aircraft and the hazard to landing operations caused by flying through turbulent path of the exhaust gases. Elimination of stacks eases topside arrangements.

7. Nuclear power provides the potential for surface ship operation independent of the atmosphere for ABC defense.

PART III. LIMITING ASPECTS

1. The increased cost factor of about 1.5 times the conventional counterparts, which has the following effects:

a. The total numbers of ships procurable within any given monetary level are reduced on a 2 by 3 ratio, which, if applied to the larger numbers in a type of ships, would mean, for example, 10 for 15. The other viewpoint is to increase that portion of the SCN appropriation for nuclear propelled ships by a factor of about 1.5, which would affect other programs in a level funding climate.

b. Increases the annual funds required in operations and maintenance appropriations (S. & F.), which are already marginal. This increase will either reduce the amounts for other ships or require an increased portion of the annual appropriation.

c. Increases both the numbers of personnel required and the amount of training involved and consequently the costs for pay, allowances, and training. The types of personnel involved are of premium quality, which further increases the Navy's requirement for this category of personnel.

d. Increases the costs involved for research and development in the nuclear propulsion field.

2. The nuclear propulsion plants as installed in the three prototype surface ships, while significantly increasing the endurance, have had the following effects:

a. Increases somewhat the size of the ship for the nuclear propulsion plant, when compared with conventional surface ships having normal endurance with otherwise similar characteristics; and for the accommodations for the increased numbers of personnel.

b. Reduces somewhat the top speeds, although the maximum sustained speeds are substantially similar, within the conventional ships' lesser endurance.

c. The DLG-16, with suitable weapons systems and electronics equipment, is about the minimum size ship in which a suitable two-reactor nuclear plant can be installed in the present state of the technology. The application of nuclear power to smaller ships such as DE/DEG or DDG would involve disproportionate increases in costs and size to maintain a balance in the combination of military characteristics.

3. The requirements for construction and maintenance facilities ashore and afloat, and repairs to damages were noted in paragraph 7 and 8 of part 1.

PART IV. CONSIDERATIONS

1. The requirements for the total number of ships in the Navy are based upon the responsibilities for multiocean operations in the national interests. The determination of the numbers of ships within the various types, carriers, cruisers, destroyers, amphbious, submarines, etc., is based upon their several functional military capabilities. These include detection systems, such as radars and sonars; the destructive capabilities of the weapons systems installed; the command and control facilities, such as communications, computers, and weapons direction systems; transportation capabilities for amphibious and underway replenishment ships; ability to influence opinion, or the deterrent capability. When provided with adequate refueling facilities, the conventionally powered surface ships of the Navy have gone where needed to carry out this multiocean responsibility.

2. There have been important degrees of improvement in weapons systems, radars, sonars, and so forth, that have increased their costs, but these improvements have extended the ranges of detection or weapons or permitted the Navy to accomplish something that could not previously be done; and, when the increased capabilities of the opposition are considered, these improvements do not reduce the requirements for the numbers of ships.

3. Similarly, nuclear propulsion is an important degree of improvement, and, like most improvements, will have an added cost, which will improve surface ship capabilities in those performance aspects affected by propulsion methods and refueling requirements. However, the improvement in propulsion and endurance aspects does not, in itself, permit the Navy to reduce the numbers of combatant ships required to meet its responsibilities.

4. The very long endurance of nuclear propulsion eliminates the need for refueling, and this begets many advantages in operational flexibility. The greatest application will probably be in that portion of the wide variety of ship employments, involving oversea movements and the independent operations of one ship or a small group of ships. The independent operations can be conducted in those areas on the seas where the usual replenishment forces are available only infrequently, for food and supplies; or for extended transits of individual ships for specialized purposes, such as intercept or search and rescue or influence missions wherein a single ship, or a small group of ships, will be sufficient. The oversea movements of forces with nuclear propulsion could be made at higher average speeds and the weather might well become the limiting factor. This ability to move some forces rapidly has a highly useful military potential in those situations where long movements may be involved and an early show of force by a selected number of ships may have distinct advantages.

5. The Navy intends to enlarge its future nuclear surface ship program in a manner that is consistent with its other requirements. The Secretary of Defense has expressed support for the Navy's intention to work toward a nuclearpowered Navy. The number of nuclear-powered surface ships that can be built under the present conditions of cost will be moderate. When the developments have progressed further so that these factors are reduced, the rate can be accelerated, for the potential advantages of nuclear propulsion are well recognized.

APPENDIX 2

THE SECRETARY OF THE NAVY,
Washington, March 30, 1962.

Memorandum for Deputy Secretary of Defense.

Subject: Nuclear propulsion development program.

Reference: (a) SecNav memo for DepSecDef of March 8, 1962. Enclosure: (1) Two copies of report "The Navy's Nuclear Propulsion Development Program."

1. In your memorandum of February 27, 1962, you requested more complete information on the Navy's nuclear propulsion program including historical data, status, and predictions for the future with particular emphasis on low weight and compact plants.

2. Reference (a) was forwarded as an interim reply to your memorandum. As noted, the enclosure to reference (a) presented a great deal of pertinent information on this subject.

26-152-64--14

3. Enclosure (1) presents history, status, and progress on the development of nuclear propulsion plants for the Navy. The Navy's past attempts to achieve low specific weight and compact propulsion plants, both conventional and nuclear, are discussed.

4. The present course of naval nuclear propulsion development which is concentrated on pressurized water-type reactor plants has evolved from work on many reactor coolants and reactor plant concepts; it is not merely an extension of the original Nautilus work. Starting with the first naval reactors studies, extensive work has been done on gas, liquid metal, organic, and heavy water reactor cycles as well as on pressurized water. Based on the accepted characteristics of each of these concepts relative to safety, reliability, maintainability, operability, cost, size, and weight, the Atomic Energy Commission (AEC) and the Navy have concluded that the pressurized water reactor plant will continue to be the best for naval propulsion application for the foreseeable future. All of the other proposed cycles have major disadvantages compared to pressurized water for naval propulsion as discussed in appendix C of enclosure (1). The Navy will, of course, continue to keep abreast of the AEC's reactor development program so that any new technology which may be developed will be evaluated with the AEC for possible application to naval ships.

5. Extensive development of pressurized water technology since Nautilus has resulted in major improvements in plant simplicity and reliability, accessibility for maintenance and overhaul, and greatly extended reactor core life. During this same period nuclear propulsion costs have been reduced significantly in marked contrast to the general trend of rising costs. There is now available a family of nuclear propulsion plants ranging in size [classified matter deleted] capable of powering every type of combatant ship, both submarine and surface, designed to carry the latest antiair or antisubmarine weapon systems.

6. In addition to work on reactor plant cycles, extensive effort has been devoted to various propulsion plant concepts in the attempt to achieve improved characteristics including lighter weight, compactness, and lower cost for naval nuclear propulsion plants. The nonreactor plant portions of these installations comprise almost one-half of the total volume and weight of these nuclear propulsion plants. These efforts have indicated that novel propulsion plant concepts, such as those based on aircraft technology, have not yet shown sufficient promise for conventional naval installations to warrant their serious consideration in conjunction with the more difficult nuclear plants.

7. In response to the Navy's requirements, considerable effort has gone into minimizing the size and weight of all of our naval nuclear propulsion plants. Detailed mockups have been built for each plant in order to optimize arrangements for minimum space and weight. In addition, extensive engineering testing including intensive operation of full-scale land prototypes has resulted in minimum size and weight of components for the greatly extended endurance of nuclear propulsion plants. There appears to be no prospect of significantly decreasing size or weight of nuclear propulsion plants for the foreseeable future without unduly and unwisely sacrificing essential requirements.

8. Modern military needs have generated added requirements for increased shockproofness, larger sonar, higher powered electronics and other weaponry for both submarines and surface ships, together with greater operating depth and quietness for submarines. All of these new characteristics require increased weight and space. For example, the displacement of attack submarines which use the S5W reactor plant has increased from 3,500 tons in Skipjack to about 4,300 tons for the latest attack submarine designs. This 800-ton (23-percent) increase has been due principally to nearly [classified matter deleted] the operating depth, sound mounting propulsion plant components, and greatly improved sonar capability. The reactor plant weight has remained substantially unchanged. Thus, factors other than nuclear plant design criteria have had a significant effect on the growth in size of our nuclear submarines. These same general growth trends have been experienced in our surface ships. It is significant that experience with designing the Navy's modern frigates, cruisers, and carriers has shown that there is no major difference in size and displacement of ships, with similar military characteristics, whether they are conventionally or nuclear powered.

9. It is difficult to assess the effect a successful development of a low specific weight nuclear powerplant might have on the Navy's future shipbuilding program without knowing the cost of the successfully developed plant. Cost has been the major factor affecting the number of ships in all shipbuilding programs.