Download eBook for Free

FormatFile SizeNotes
PDF file 1.4 MB

Use Adobe Acrobat Reader version 10 or higher for the best experience.


Purchase Print Copy

 Format Price
Add to Cart Paperback166 pages $28.50

Research Questions

  1. What modularity and flexibility concepts should the Navy apply in future shipbuilding programs?
  2. What changes in a ship's capability may be needed in the future?
  3. When are the future opportunities to adapt modular and flexible designs in future naval ship programs?

In the face of challenges to acquire and support the numbers and types of ships needed to meet national security requirements in an environment of rapid change and shrinking defense budgets, this report explores the U.S. Navy's options for extending the service lives of operational ships by adopting the concepts of modularity and flexibility in ship design. These concepts can help to mitigate the risks of uncertain future missions and technologies to which ships will need to adapt, as well as potentially reduce modernization costs and/or initial cost.

The report examines the concepts of modularity and flexibility, technological trends, the current geopolitical context, and lessons from past incorporation of new missions and technologies into naval ships. It also provides a roadmap for future U.S. Navy modularity and flexibility efforts.

Key Findings

Cost effects of modularity and flexibility

  • Construction costs can be reduced through the economies of scale provided by common components and by any reduction in welding and other hot work done in a factory versus during ship construction. On the other hand, flexibility that leads to larger ships could also lead to higher acquisition costs.
  • Modularity and flexibility should have little or no effect on the equipment cost of a modernization work package, but can have a large effect on the cost of installing and testing the new equipment or system.

Future adaptations

  • In the coming decades, the U.S. military may face a wider range of potential adversaries, as some states may rise to near-peer levels and non-state actors acquire more advanced capabilities. U.S. Navy ships need to be prepared to accommodate the diverse mission sets needed to counter such a range of adversaries.
  • Four major technological trends will likely influence naval operations over the coming decades: (1) Rapidly increasing use and effectiveness of off-board unmanned systems, (2) the growing importance of using the electromagnetic spectrum as a weapon, (3) enhanced capabilities for long-range targeting, and (4) the increasingly networked nature of the battlespace.
  • All of these trends involve rapid change and inherently unforeseeable technological developments. However, by endowing ships with more capacity or capability than immediately needed in five areas, it is possible to make them better able to accommodate these trends. These five areas are power, cooling, support for personnel, space, and bandwidth.

Future opportunities for modularity and flexibility

  • The primary place to inject modularity and flexibility concepts is early in the ship concept design phase.
  • In the near term, only two opportunities for new or updated designs present themselves: the DDG-51 Flight III and the LX(R) programs.


  • For the DDG-51 Flight III program, new walls and floors should adopt the same flexible infrastructure track and interface concepts used in the Ford-class aircraft carrier design. Second, the Navy should design and build common hotel-related modules that could ultimately be used across multiple ship classes.
  • Flexibility suggests the LX(R) should be even longer and have more power-generation capability. The LX(R) design should also continue to incorporate various payload modules. It should consider large, open hangar bays with connections for those payload modules. Finally, it should consider flexible infrastructures and common modules that can be used across multiple ship classes.
  • The Navy should continue to encourage and develop the concepts of modularity and flexibility, but in a more focused and coordinated fashion. Evaluate the potential for common foundations for certain classes of equipment (such as the standard racks used for computer-related equipment) and standard connections for the ship service interfaces between spaces. Also, evaluate the potential use of common hotel-related or other types of modules for use across different classes of ships. For example, a scalable modular concept within the design production model tool for a future class of ships could be exported for use across other ship designs. The use of a rail gun is an example of a module on future ship classes.
  • The Navy should continue to develop a single organization to manage repair and modernization work packages in a coordinated manner. This organization should also have the mission of developing future modularity concepts that cut across ship classes and initiate conceptual and feasibility designs for interfaces and payload modules. It should work with the major weapon system developers and manufacturers.
  • The Navy should collect, organize, and analyze modernization work package data to gain a better understanding of the cost of modernizing in-service ships, including what drives costs and how those costs could be reduced if more modularity and flexibility were incorporated into ship designs.

This research was sponsored by the U.S. Navy and conducted within the Acquisition and Technology Policy Center of the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community.

This report is part of the RAND research report series. RAND reports present research findings and objective analysis that address the challenges facing the public and private sectors. All RAND reports undergo rigorous peer review to ensure high standards for research quality and objectivity.

This document and trademark(s) contained herein are protected by law. This representation of RAND intellectual property is provided for noncommercial use only. Unauthorized posting of this publication online is prohibited; linking directly to this product page is encouraged. Permission is required from RAND to reproduce, or reuse in another form, any of its research documents for commercial purposes. For information on reprint and reuse permissions, please visit

RAND is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.