1423 Powhatan St., Suite 1
Alexandria, Virginia 22314
Phone (703) 836-6727
Fax (703) 836-7491
Email: asnehq@navalengineers.org

A Framework to Improve Systems Integration in Shipbuilding Programs Having Simultaneous Detail Design and Production

By: Fatma Nur Alkas, Michael Grenn, Ph.D., and Blake Roberts, Ph.D.

On average, building a standard US Navy ship takes 4 years from laying the keel to commissioning. During this time, the ship design keeps evolving for the units that have not been fully built yet, resulting in detail design and production of the same ship to occur simultaneously. This becomes an issue when the integration of the newly designed units and the units that have already been built is not done properly. Today's shipbuilding practices require an abundant number of Engineering Change Proposals (ECPs) due to unexpected integration requirements that emerge during detail design phases, where the concept that was previously defined gets fine-tuned for readiness for production. These changes seize more than 28% of the total ship design effort in building a standard U.S. Navy ship, increasing cost, causing delays in schedule, and even causing Navy to re-evaluate the number of planned ships for the class. To eliminate later changes due to emerging systems integration requirements, it is crucial to understand system-to-system interrelationships and consider these during Systems Requirements Specifications (SRS) definition process. This paper proposes a methodology for capturing the relationships between system requirements in the early stages of ship design process to minimize ECPs due to unexpected integration impacts. It also analyzes different US Navy shipbuilding programs’ approach to processing ECPs and how they handle systems integration impacts on ECPs.