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The Italian team that designed and the frigate Maestrale (F-570) and did the same for their missile cruiser Slava have more in common than meets the eye. Had either or both built the Arleigh Burke (DDG-51), she wouldn’t be as big as she is, but she probably wouldn’t have cost near as much either.
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34 feet 8,700 long tons Range
6,730 long tons Sustained
963,089 cubic speed feet
Depth Full-load displacement Light ship displacement Enclosed volume
Length 502 feet Propulsion
between perpendiculars
Beam 60.1 feet
The U. S. Navy is now designing the Arleigh Burke- class destroyer (DDG-51). Compared to U. S. warships of proportionate size, the Arleigh Burke promises to be one of the most seaworthy and survivable destroyer-type ships ever developed for naval service. With advanced electronic sensors and vertical launch missiles, she will also have tremendous firepower. However, although the Arleigh Burke promises to be an effective warship of about 8,300 tons full-load displacement, she is also very large and costly. How can this cost be reduced? Can the country afford a large number of these powerful warships if the U. S. Navy is ever to achieve its current goal of 600 ships?
Our recent assessments of foreign warships, particularly those of the Italians and Soviets, which appear to use very similar design practices, indicate that they are often smaller and less costly than comparable U. S. ships.1 What would a modem U. S. Navy destroyer look like if a team of Italian or Soviet ship design engineers designed her? More important, how would employing Italian or Soviet ship design and acquisition practices influence the affordability and effectiveness of the resulting ship? To answer these questions, we put on our “Italian ship designer’s hat” and, using a recent notional U. S. destroyer design as a baseline (Figure 1), developed an “affordable” version of the U. S. design with a suite of U. S. weapons and sensors similar to the one planned for the Arleigh Burke.
Ship Design Practices
Design and Construction Margins: Design and construction margins are engineering allowances for growth in the size and cost of a ship. These margins are provided early in the design process to account for uncertainties during the design process and for changes in the design that occur during the design and construction process. The U. S. designers use large design and construction margins, whereas the Italians, and we believe the Soviets, do not.
90.0 shaft horsepower, twin screw, four LM-2500 gas turbines, fixed pitch propellers, with reversing gear box
5.0 nautical miles at 18 knots 30 knots
The reasons for these differences stem primarily from the different design and acquisition environment in the United States as compared to that in Italy and other European NATO countries. Since it is assumed that margins are consumed during the design and construction process, a ship that is designed with large design margins would not necessarily be any more operationally effective, sustainable, or survivable than a similar ship designed with small design margins. However, in any given design and acquisition environment, margins must be sized in recognition o that environment to assure that a ship, as delivered, wu meet the initially specified speed, range, displacement, and stability requirements and the originally estimated cost.
Compared to aircraft and missiles, a ship is a relatively forgiving platform. Reasonable changes in displacement, for example, have only a limited impact on speed, range, or stability. The importance of design margins is, therefore, often related to the extent that ''arious ship design criteria are used as absolute measures of sufficiency. The more rigid the attitude in a particular design and acquisition environment toward the inviolability of the ship design criteria or performance characteristics, the larger the margins that will be required to ensure success.
Table 1 lists the typical design and construction margins used by the United States and Italy and the margins selected for use in the affordable destroyer design.
Ship Protection: The survivability of ships can be enhanced by providing both passive protection features and active protection features—weapons, sensors, and electronic warfare equipment—and operational tactics. Recent naval combat experience indicates that many ships have inadequate weapons and sensors. In addition, the effec" tiveness of the operational tactics used by navies is often not up to that required for survival in a modem combat environment. Active protection for ships, which is under the cognizance of the combat system design engineer, lS beyond the scope of this study. We are concerned with the impact of passive protection features of ship design that are within the cognizance of the ship designer, who >s responsible for designing the ship as a platform—including the machinery and electrical systems—and integrating the combat system, or payload, and the platform into a total ship system.
The ship designer is responsible for ship design prac' tices and criteria that result in reduced ship signatures radar, infrared, magnetic, and acoustic. By reducing a ship’s signatures, the efficiency of the ship’s own weapons and sensors can be increased and the probability of her being located, classified, and targeted by an enemy decreased. The ship designer is also responsible for limiting the impact and progression of damage to a ship once she is hit, by providing ballistic protection, steel or special insulated aluminum superstructure, redundant and distribute vital systems, distributed and protected command, control, and communications systems, protected ammunition, and distributed damage control systems.
All surface ships are vulnerable to certain lethal antiship weapons. Therefore, these listed passive protection fea' tures are generally effective only against weapons that
Item | Typical U. S. | Italian | Affordable |
height Vertical center | 10-12.5% | 2.5% | 5% |
of gravity | ~5% | 2.5% | ~5% |
Power | 10% | None | 5% |
Deck area | 5% | None | None |
Range | 30% | 5% | 10% |
Electrical power | 25% | None | 10% |
cannot readily sink ships but can degrade or destroy vital systems. The warship protection concepts of NATO countries and the Soviet Union differ widely from one another. There is not one country, including the United States, that appears to provide balanced all-around passive protection for its ships. Current, typical U. S. passive protection Practices incorporated in the notional baseline destroyer design are compared to typical Italian and estimated Soviet practices in Table 2. The ship protection features chosen for use in the affordable design are also shown.
In-Service Margins: In-service margins are engineering allowances provided early during the Resign process to account for changes to a ship during her future operational lifetime. These in-service margins are maintained intact during the entire design and construction process, so as to be available for use at the time of delivery of the ship to the fleet. The United States uses large in-service margins; 'n general, Italy and most European NATO countries, and We believe the Soviet Union, use small in-service mar
gins. What accounts for this diversity? Probably the difference in the maintenance management discipline used during a ship’s lifetime, the difference in midlife conversion philosophy, and the expectation that future weapons and sensors will be lighter than the systems they replace. As in the case of design and construction margins, the differences in the approach various countries take to in-service margins reflect their attitudes toward ship design criteria. The more rigid the attitude toward the inviolability of the ship design criteria or ship performance characteristics, the larger the margins required. Typical in-service margins used by the United States and Italy (and probably the Soviets) and those selected for use in the affordable destroyer design are shown in Table 3.
Sustainability: The principal ship design features that contribute to a ship’s ability to sustain underway operations for long periods without special support from shore- based facilities include:
► Adequate level of manning
► Provision of well-equipped workshops, adequate spares arranged in efficient storerooms, and good maintenance management facilities
► Accessibility for equipment maintenance
► Provision of replenishment-at-sea (RAS) and stores strikedown facilities
A ship designed with good sustainability will incorporate these features to some degree. The sizes of recent U. S. ships, which make regular lengthy deployments, reflect the impact of sustainability design features in each of these areas. The most recent Soviet surface combatants, the Kirov, Udaloy, Sovremennyy, and Slava, are volumet- rically larger than would have been expected, based on
Table 2 Passive Protection Practices
Item Typical U. S. Italian Affordable
Superstructure material | Steel | Aluminum | Steel |
Use of vital spaces | Yes | None | None |
Shock protection | NATO standards | NATO standards | One-half NAT standards |
Blast resistance | 7 pounds per square inch | Inherent | 3 pounds per square inch |
Nuclear, biological, and chemical collective system Signature reduction: | Complete | None | Partial |
Acoustic | DD-963 levels, with low RPM propellers and Prairie/Masker | Limited | Limited |
Infrared | CG-47 levels | Stack eduction | Stack eduction |
Radar | Radar absorbing material topsides, plus slope and shape | None | Slope and shape |
previous Soviet design practices. Since Soviet ships are now regularly conducting lengthy deployments, one reason for this increase in space could be the need for better maintenance facilities and more accessibility to equipment for maintenance.
For this study, the same manning level as provided on the baseline destroyer design was assumed. The various other ship design features associated with sustainability were considered to be the same as Italian (and estimated Soviet) practices. (See Table 4).
Habitability: Since World War II, the habitability standards for U. S. ships have been continually improved. Sailors today have considerably larger, more spacious berthing, messing, sanitary, and support facilities. Also, the average deck height in U. S. ships has been increased. A minimum clear deck height of six feet five inches is now used as a design goal. As a result of these improvements, U. S. Navy ships now provide about 600 cubic feet per accommodation—compared to about 250 cubic feet per accommodation in 1945. In addition to the space for habitability, U. S. Navy ships are now air-conditioned, well insulated against noise, and have attractive deck coverings, joinerwork, and furniture. As shown in Figure 2, U. S. habitability standards are about average in relation to the standards of other NATO countries.
Soviet habitability standards have been considerably improved in their newest ships. Current Soviet habitability deck area standards are supposedly approaching U. S. standards for enlisted personnel and are equal to or greater than U. S. standards for officers and chief petty officers. Soviet and Italian habitability standards are estimated to be very similar. By U. S. standards, Italian ships use lower deck heights, more austere outfitting, and less effective habitability-related auxiliary systems. Using current U. S. standards as a baseline in relation to current Italian
standards, habitability design standards for the affordable destroyer design were assumed as shown in Table 5.
Hull Form: Each NATO navy has its own approach to the development of destroyer-type hull forms. The hub forms of Italian and Soviet ships are very similar.2 This style hull form is generally characterized by flare through the waterline along the length of the ship, V-shaped sections forward, a wide waterplane aft, a broad transom, alU a midship section with high, straight deadrise, and a sharp turn to the bilge.
Hull form influences a ship’s powering and seakeeping performance, stability, and internal arrangements. Like most areas of ship design, the choice of hull form is a compromise among these characteristics. An Italian-style hull form was used for the affordable destroyer design. As compared to the hull form of the U. S. baseline design, the Italian-style hull form is characterized by relatively more stability, more deck area, better high-speed resistance characteristics, better seakeeping performance, and more wetted surface.
Table 3 In-Service Margins |
| Table 5 Habitability Standards: Affordable Design | |||
Item | Typical U.S. | Italian | Affordable | Compared to U. S. | Standards |
Future growth weight | 50 long tons | None | 50 long tons | Officer living spaces | —Larger two-man cabins |
Accommodations | 10% | None | None | Chief petty officer living spaces | —Four-man cabins, |
Service life | 10% | None | Small |
| sleeping two high |
displacement Service life KG Auxiliary system loads | .5 foot 20% | None None | None None | Enlisted living spaces | rather than ten- to 20-man bunkrooms, sleeping three high —Smaller, three-high berthing with mini- |
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Table 4 | Sustainability Features |
| Support spaces | —More austere than | |
Item |
| U. S. | Affordable | Deck heights | on U. S. ships |
Deck area for support spaces Deck area for maintenance within spaces Deck area dedicated for access | Extensive Extensive 22% | Limited Limited 12% | —Lower clear deck heights than on U. S. ships; 6'2" clearance on second deck | ||
RAS facilities |
| Extensive | Limited | Outfitting | —More austere |
Stability: Each NATO navy has its own method for calculating the intact and damaged stability of warships at different design displacements or loading conditions. The U. S. Navy uses compensating saltwater ballast as fuel is consumed to maintain a ship within specified stability lim- 'ts at or near her full-load displacement. The Italians (and We believe the Soviets) employ a different method. Their ships are designed at the “mean trial” displacement, which is an average displacement with a partial load of consumables and fuel on board. They are stable, within specified limits, with very little fuel on board and without needing to use saltwater ballast. Mean trial displacement Was used for calculating the stability, speed, and range of the affordable destroyer design. This method is compared •o the U. S. method in Table 6.
Machinery: Machinery plant design practices used by NATO and Soviet navies vary considerably. By U. S. standards, Italian and Soviet machinery plants have been characterized by tight arrangements, which is reflected in a very low specific machinery volume. It is estimated that this tightness results because they emphasize provision of equipment shock protection, separation and redundancy for survivability, accessibility for maintenance, and noise reduction for antisubmarine warfare operations less than the U. S. Navy does.
One important difference between U. S. and Italian niachinery plant design and acquisition practices helps explain how Italian ships achieve tighter machinery plant arrangements. It is Italian practice for the shipbuilder to construct the ship exactly as designed (unless changes are necessary) and to install the equipment specified in the contract design package. U. S. ship acquisition practice, on the other hand, allows a shipbuilder considerable latitude in the detail design of a ship and the selection of ancillary and auxiliary machinery equipment. Therefore, to allow for competition in the acquisition process, allowances are made in the design for the largest equipments on the market, so that any qualified manufacturer could supply the equipment.
The United States designs ships for extensive on-board maintenance, whereas Italian on-board maintenance requirements are tailored to missions of a few weeks duration. This is consistent with Italian Navy operations in and out of well-equipped ports. However, the Italians do pro-
Table 6 Stability Practices
Item | U. S. | Italian |
Hull form calculation | Full load | Mean trial |
Speed calculation | Full load | Mean trial |
Endurance calculation | Full load | Mean trial |
Minimum operating con- | Near full | Light ship + |
dition | load | 1/10 consum ables |
Stability, in terms of | 10% at full | 7% at minimun |
metacentric height/beam ratio during early design stages | load | operating condition |
vide sufficient access space for in-place disassembly. Also, they provide access routes for machinery removal, which appear adequate, notwithstanding their tight overall machinery arrangements.
U. S. machinery design practice provides both redundancy and a margin for growth in auxiliary equipment, such as electrical generating plants, air conditioning, and distillers. Italian practice does not.
The propulsion plant of the U. S. baseline destroyer design consists of two shafts with controllable pitch propellers. Each shaft is powered by two LM-2500 gas turbine engines. The Soviets, in the case of the “Kara”-class cruiser and the “Krivak”-class frigate, and the Italians, in the case of the Garibaldi-class carrier, use two shafts with fixed pitch propellers and reverse reduction gears. Each shaft is powered by two gas turbine engines; the Garibaldi employs LM-2500 engines. The propulsion plant chosen for the affordable destroyer design consists of two shafts with fixed pitch propellers and reverse reduction gears, with each shaft powered by two LM-2500 engines.
A volumetrically tight propulsion plant arrangement was developed for the affordable design. Consistent with the estimated Soviet machinery arrangement in the “Krivak” and “Kara” classes, all four gas turbines were colocated, with only one stack/intake topsides. To enhance survivability, a centerline bulkhead was provided to separate the main machinery space into port and starboard compartments. Enough space was provided in the auxiliary machinery rooms to achieve a specific machinery volume equal to that of the newest Italian and Soviet gas turbine-powered ships. The arrangement of the machinery spaces of the notional U. S. baseline design and the affordable design are shown in Figure 3.
Ship Acquisition Practices
In the United States, Naval Sea Systems Command (NavSea) generally prepares a contract package of drawings and specifications based on a contract design which, in turn, is based on the results of earlier design stages. These designs are the result of an in-house engineering effort, although NavSea engineers are generally assisted by commercial design agents. NavSea reports ship design characteristics and estimated ship costs to the upper levels of Navy management early in the design process, starting with the results of early feasibility studies. The NavSea contract package is used as the basis for competitive bids by commercial shipbuilders, which will use many components and equipment that will also be procured on a competitive basis. Hence, in some instances, the potentially largest, heaviest, and costliest components and equipment must be allowed for during the design process. The contract between the shipbuilder and the Navy is very detailed in its specifications. These ship acquisition practices explain the necessity for the use of large design and construction margins.
Some European NATO navies, of which the Italians are an example, have a different ship design and acquisition strategy. In Italy, the feasibility design is developed inhouse by a small, stable, naval design team in coordina-
Figure 3 Machinery Arrangements -
Notional U. S. Baseline
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| n | LM-2500 1 | | D-G SET | |d-gset| | |
| LM-2500 | 0 | [ D-Q SET | |
| Li | LM-2500 | | |
___ | LM-2SOO |
Specific
Machinery
Volume:
3.3 cubic feet/ shaft horsepower
Affordable Design
Auxiliary Macftine Auxiliary Machma Auxiliary Maehma
Rbom Room Room
No 3 Moom No 2 No 1
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1 ' j | | D-G SET | | ,tssJn | LM-2500 [-1 1 |
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Specific
Machinery
Volume:
2.1 cubic feet/ shaft horsepower
tion with the naval operational planning and procurement specialists. The results of the feasibility design and estimated ship cost are not formally reported to top-level navy management. Rather, the feasibility design is passed on to a commercial shipyard or shipyards, which then prepare their own proposed contract design. The contract design is often awarded on a sole-source basis to both the shipbuilder and the equipment suppliers. A shipyard’s contract design is based on the navy’s original feasibility design but is changed as required to reflect the shipyard’s design and production ideas and to incorporate input from selected equipment suppliers, with the approval of the navy technical staff. When major changes are made to the ship during the design process, it is often redesignated as a new project. Therefore, consistent with these ship acquisition practices, very little growth in light ship weight or vertical center of gravity is allowed for within preplanned margins. The cost of the ship is formally estimated by the shipbuilder and given to the top levels of the navy for a procurement decision only after the contract design stags is completed.
Many European NATO ship designs, including those of Italy, are developed using standardized components and equipment, which are often procured without CompetitionEngineering staff and management turnover in European NATO naval ship design offices and shipyards is relatively low, and the construction contract between the shipyard and the navy is relatively simple. In addition, Italian shipyards guarantee ship performance—generally stability’ speed, and endurance—and warrant the ship’s equipment- Contractual penalties are also provided in the form of negative fee incentives if the ship fails to meet these performance requirements during trials. NavSea engineers who have visited European NATO naval design offices and commercial shipyards have not observed the arms-length and often adversarial relationship found in the United States between the Navy and commercial shipyards. Also, the Italian shipyards visited use rigorous weight control procedures that enable design engineers to closely monitor actual ship weights. This provides Italian design engineers with an excellent data base from which to estimate the weight of future ships. In addition, change orders for ships under construction are few in number. The major differences in U. S. and Italian ship acquisition practices are summarized in Table 7.
Table 7 Design and Acquisition Process
Item U- S. Italian
Design team | Primarily civilian, low turnover, but limited continuity | Military and civilian, low turnover |
Feasibility design: | ||
Location | In-house | In-house |
Method | Manual and computerized studies | Manual studies |
Data base | Extensive | Limited |
Contract design: | ||
Location | In-house, some shipyard input | Shipyard |
Corporate memory | Acceptable | Excellent |
Procurement: | ||
Contract | Detailed | Relatively simple |
Specifications | Extensive, specific | Limited, functional |
Change orders | Numerous, within margins | Few, new project designation when required |
Shipyard warrantees | Limited | Extensive |
Weight control | Minimal | Extensive |
Penalties on ship performance | Minimal | Negative incentive fee on spe< endurance, and stability |
Using Italian (and estimated Soviet) ship design practices and criteria, an affordable destroyer design was developed (Figure 4). The affordable design is substantially smaller than the notional U. S. baseline design, as shown •n Table 8.
The affordable design carries the same payload of weapons and sensors as the baseline design. It has smaller design and construction margins, a more tightly arranged machinery plant, fewer passive protection features, smaller in-service margins, less space provided for sustainability, less space for habitability, a different hull form, and is designed to a different set of stability criteria. It has the same range; however, it is designed with smaller endurance margins. Both it and the baseline design use four LM-2500 gas turbines with fixed pitch propellers. The affordable design has 80,000 shaft horsepower and a sustained speed of 29 knots, instead of the baseline design’s 90,000 shaft horsepower and 30 knots. These changes to the notional U. S. design are within the state- of-the-art in U. S. technology.
Length | 385 feet | Propulsion |
Beam | 59 feet |
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Depth | 36 feet |
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Full-load | 5,750 long |
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displacement | tons | Range |
Light ship | 4,455 long | |
displacement | tons | Sustained |
Enclosed | 704,421 cubic | speed |
volume | feet |
80.0 shaft horsepower, twin screw, four LM-2500 gas turbines, fixed pitch propellers, with reversing
gear box
5.0 nautical miles at 18 knots 29 knots
Table 8 Physical Characteristics
Item | Baseline Design | Affordable Design | Reduc tion |
Light ship displace- | 6,670 | 4,460 | 33% |
ment, long tons | |||
Full-load displace- | 8,700 | 5,260 | 40% |
ment, long tons | |||
Fuel oil load, long tons | 1,690 | 970 | 43% |
Useable deck area, | 56,900 | 39,300 | 31% |
square feet | |||
Total enclosed volume, | 963,100 | 704,400 | 27% |
cubic feet | |||
Average deck height, feet | 10.4 | 8.8 | 15% |
Design and Acquisition: In the absence of more effective planning and discipline in the ship design and acquisition process, current practice is to provide large margins, which then, for the most part, become self-fulfilling prophesies. The small design and construction margins that were used in the study for the affordable design would not be feasible unless the U. S. Navy significantly modified its ship acquisition practices and the discipline with which they are executed. Small margins would be practical only if acquisition practices like those of Italy were used—practices which (1) minimize Navy involvement after completion of a thorough feasibility design, (2) allow shipyards to develop their own competitive contract ship designs based on the Navy’s feasibility design, with only a minimum of additional input from the Navy, (3) allow the successful competing shipyard to complete the detail design and construction with relatively few changes, and (4) use functional specifications, contractual ship performance warrantees, and a modest amount of Navy on-site supervision in lieu of demanding, detailed specifications and extensive Navy on-site supervision.
Survivability: Certain antiship weapons today cannot be defeated by passive protection features in frigate- and destroyer-sized ships in any practical way. More than one- half the cost of a U. S. ship consists of complex weapons and sensors, many of which are concentrated in the forward superstructure area where they are susceptible to simultaneous damage from a single weapon hit, and all of which have long lead times for acquisition. Therefore, the time and cost to repair a war-damaged ship may not be significantly reduced by passive protection features, and the value of a survivable platform that requires extensive repair or replacement of its combat system may be less than the probability of ship survivability would suggest. Moreover, as indicated by World War II experience, damaged ships that are immobile or that cannot defend themselves can be a major liability to operational commanders. For these reasons, it might be worthwhile to consider reducing some expensive passive protection features that would not reduce crew survival or the ability to quickly abandon ship, and to use the resources saved to increase active protection features or to acquire additional ships.
In-Service Margins: Small in-service design margins are feasible for the U. S. Navy only if it more effectively controls the growth in displacement, center of gravity, and auxiliary system loads during a ship’s long in-service life. For example, in Italy, shipyard commanders are reported to have the time and the authority to return a ship to the originally specified loading condition by “stripping” her of unauthorized load weights. In the United States, shipyards are given only a minimum amount of time and resources to measure a ship’s displacement and center of gravity, and rarely are ships stripped of unauthorized load weights. Our study indicates that in-service margins have only a minimal impact on ship size and cost. However, as they are used in service, the speed and range of a ship will decrease.
Sustainability: Sustainability is a complex issue. There are no data available that clearly demonstrate that the smaller, affordable design would not be as sustainable as
the U. S. baseline design. U. S. naval experience during and after World War II, which has always featured sustained operations, has relied successfully on ships with features similar to those on the affordable-sized ship. Nevertheless, ship designers, in response to fleet requirements, have continued to add more space in new ships. We think this requirement for more space has been driven largely by the pressure of peacetime operational, training, and personnel retention requirements. Therefore, the extent to which future ship designs are driven by peacetime sustainability requirements should be continually reassessed in light of the capability and number of ships we need and can afford for war.
Habitability: In the Falklands Conflict, the Royal Navy found that many ship design features that were provided to improve habitability—deck covering, furniture, and joinerwork—were damage control liabilities. As in the case of sustainability, the extent to which shipboard habitability is influenced by peacetime vice wartime requirements should be reassessed. This should include an assessment of the relationship between habitability and its payoff in improved personnel performance and retention.
Hull Form and Stability Criteria: Our study indicates that hull form and stability criteria have only a minimal impact on ship size and cost. Therefore, their choice should remain the ship designer’s, with appropriate guidance from the operator on the relative priorities of calm and rough water speed, seakeeping performance, and conservation of fuel.
Machinery: In comparison to the U. S. baseline design, the affordable design has a much tighter machinery arrangement. Yet, the smaller machinery box in the affordable design was not achieved by providing less capability or by using physically smaller equipment. The closer spacing among equipments achieved by minimizing access space for maintenance and the better use of all the space in a machinery space—the vertical space as well as the horizontal space near the deck—contribute to the tighter machinery arrangement in the affordable design. Yet, there still appears to be sufficient room to meet maintenance requirements, including component disassembly, removal, and replacement.
Contributing to the Italian designers’ achievement of tighter spacing of equipment is their tighter control over the ship design and acquisition process. Experience has shown that the additional space allowed by U. S. engineers in the early design stages does not always ensure adequate access to equipment for maintenance when tight control is not kept over detail design and construction.
Cost: Our study addressed only the impact of modified Italian design practices on basic ship size—the results indicating that these practices would reduce the size of the notional U. S. design by about 33%. A previous study has indicated that Soviet ship design and acquisition practices would reduce the cost per ton of light ship by about 25%. Assuming that the platform cost of the U. S. baseline design currently represents about 45% and the combat system about 55% of the overall acquisition cost, the smaller affordable design would cost only about 78% of the total acquisition cost of the baseline design. This same reduction, however, would not be achieved in life-cycle cost; because, although the cost of fuel would be less, the cost of ammunition, stores, and manning would remain the same, and the cost of maintaining and overhauling a smaller, tighter ship would probably increase.
For a reduction in acquisition cost of about 20-25%, the U. S. Navy would have to change its acquisition, operation, and maintenance practices. It would also have to accept a decrease in survivability, more austere operating and living conditions for the crew, and potentially more difficult and expensive on board maintenance and overhauls. Moreover, because the affordable design would be smaller than the baseline design, the resulting ship would have less seakeeping capability and, therefore, would be potentially less effective in conducting operations under the severe open-ocean conditions of the North Atlantic, where the Soviet Navy operates many of its ships.
Therefore, reducing ship acquisition cost by reducing ship size should not be undertaken unless there is a sim1' larly effective effort undertaken to reduce combat system cost. Otherwise, we may end up with a ship platform not worthy of the combat system.
Conclusions
The modified Italian design practices and acquisition process described herein might not be adequate for the U. S. Navy. On the other hand, their use could potentially achieve a reduction in ship size (Figure 5) and an estimated ship acquisition cost-savings of about 20%. However, ship designers, no matter how clever or cost-saving their concepts, cannot make a decisive impact on the cost of new warships by themselves. Ship cost is primarily influenced by the fleet planning organization, which must decide what kind of war will be fought, the resources available, and the characteristics and numbers of ships required to win. Ship cost is secondarily influenced by the acquisition organization, which must use a strategy and a discipline that controls change orders and minimizes the growth in cost during the acquisition process. Only then can ship designers, as part of the acquisition process, de-
Item | Percent Reduction |
Useable deck area | 31 |
Average deck weight | 15 |
Enclosed volume | 27 |
Light ship displacement | 33 |
Fuel oil load | 43 |
Full-load displacement | 40 |
| ___ |
s>gn ships with the required characteristics, which are affordable and in the required numbers.
If the U. S. Navy is to improve the affordability of future warships, in its effort to achieve a goal of 600 ships, U must recognize that its ship design and acquisition prac- hces and the discipline with which they are executed must changed. What those new practices should be remain to ^ identified. They need not be patterned on Italian prac- bces, or on those of any other country. However, like the U- S. automobile industry, the U. S. Navy could facilitate *js efforts in identifying new design and acquisition practices by studying the ship design and acquisition practices °f other countries.
lames W. Kehoe, Clark Graham, Kenneth S. Brower, and Herbert A. Meier, Comparative Naval Architecture Analysis of NATO and Soviet Frigates,” Naval Engineers Journal, October 1980, pp. 87-99 and December 1980, pp. 84-93; ^ehoe, Graham, Brower, and Meier, “NATO and Soviet Ship Design Practices,” international Defense Review, No. 7, 1980, pp. 1003-1010; Kehoe, Brower, and ^leicr, “U. S. and Soviet Ship Design Practices, 1950-1980,” Proceedings, May 1982, pp. 118-133; Kehoe, Brower, and Meier, “Impact of Design Practices on Ship Size and Cost,” Naval Engineers Journal, April 1982, pp. 68-86.
James W. Kehoe, Kenneth S. Brower, Herbert A. Meier, and Eric Runnerstrom, U.S. and Foreign Hull Form Machinery and Structural Design Practices,” Naval Engineers Journal, November 1983, pp. 36-53.
Captain Kehoe is well known for his work in conducting comparative engineering analyses of U. S. and foreign warship design practices at the
Naval Sea Systems Command. He is currently a partner in Spectrum Associates, Inc. Prior to his retirement from the Navy in 1982, he served in three destroyers and three aircraft carriers, including command of the USS John R. Pierce (DD-753) and engineer officer of the USS Wasp (CVS-18). Ashore, he has had duty in nuclear weapons, the Polaris missile program, and instructing in project management.
Mr. Brower is a partner in Spectrum Associates, Inc., which he founded in June 1978. He graduated from the University of Michigan in 1965 with a bachelor’s degree in naval architecture. He has contributed to the design of numerous merchant ships and warships. Since 1972, he has actively supported the Naval Sea Systems Command’s comparative naval architecture program. During this period, Mr. Brower has contributed to or been the author of numerous technical reports on international ship design practices. He has contributed as an analyst, editor, and author to an extensive assessment of the engineering design practices of tanks, missiles, aircraft, ships, and electronics.
A graduate of the University of Michigan in 1951 with a bachelor's degree in naval architecture, Mr. Meier was employed by the Bureau of Ships and Naval Sea Systems Command as a naval architect in the offices responsible for the conceptual and preliminary design of U. S. warships from 1951 to 1976. During this period, he was the project naval architect on several classes of combatants and auxiliaries. He was also the senior civilian engineer working in support of the comparative naval architecture program since its inception in 1972. Mr. Meier is now the senior consulting engineer for Spectrum Associates, Inc., devoting much of his time to continued work on the comparative naval architecture program and warship feasibility design studies.
__________________________________________ A Bull at Gedunk Time_________________________
We were en route in the USS New Jersey (BB-62) to the Admiralty Islands during July 1944. The ship sailed within a box formed by our four destroyer escorts, two destroyers slightly ahead of us and two slightly astern on each side. It was another beautiful day. Cruising at 22 knots, the ship and her escorts cut creamy white paths through the deep blue water.
About 32 hours had passed since the ship left Pearl Harbor, steamed past Waikiki and Diamond Head, and turned her stem toward a bright sun rising in the east. We had returned to Pearl Harbor for some navy yard repairs. During our six-day port visit, we loaded food, ammunition, fuel oil, and mail. We had each managed to visit Honolulu and Waikiki two or three times.
A voyage like ours is generally pleasant. However, it is also monotonous. Accordingly, we looked forward to our late afternoon break. Sailors call it gedunk time, and it occurs at about 1530 every day. A gedunk is nothing more than a creative ice cream concoction. All large Navy ships have a soda fountain that dispenses many types of concoctions.
The New Jersey's complement was about 2,800 officers and men; about half of these were gedunk-lovers. Since the supply of ice cream frequently did not meet the demand, an orderly system for service was devised. First and foremost, all on board were considered equal. Officers and crew alike lined up in a single line, which wended its way from the main deck, down a ladder, and past the soda fountain. Service was amazingly fast.
Shipboard etiquette did not tolerate anyone crashing the gedunk line. Consequently, when two very new junior officers pushed ahead of a young seaman, angry murmers rippled along the line. A loud growl behind me demanded that the junior officers go to the end of the line. The growl became a roar when the officers failed to move. I turned to identify the source of the roar. It was the Bull—Admiral Bill Halsey. At about this time, the junior officers turned to study the commotion they had caused. When they realized they were the subject of the Bull’s wrath, they fled the scene, and probably took refuge in their cabin. A happy Bull patiently resumed his position in line.
Ellis S. Mamroth
(The Naval Institute will pay $25.00 for each anecdote published in the Proceedings.)