Procedures for Early-Stage Naval Ship Design Evaluation of Dynamic Stability: Influence of the Wave Crest

2010 ◽  
Vol 122 (2) ◽  
pp. 93-106 ◽  
Author(s):  
VADIM BELENKY ◽  
CHRISTOPHER C. BASSLER
2014 ◽  
Author(s):  
Robert G. Keane ◽  
Laury Deschamps ◽  
Steve Maguire

The Office of the Under Secretary of Defense, Acquisition, Technology and Logistics (AT&L) recently presented analyses of cost and schedule growth on Major Defense Acquisition Programs (MDAPs)over the last 20 years (2013, 2014). For naval ships, AT&L (2013) concluded that contract work content growth (not capability growth) dominates total cost growth statistically. In addition, costs-over-target are significant and reflect poor cost estimation or faulty framing assumptions. AT&L (2014) also concluded prices on fixed-price contracts are only “fixed” if the contractual work content remains fixed, but this is often not the case. The authors show that under-sizing the ship during concept design studies increases ship outfit density and adds complexities to the design. These early stage design decisions on sizing the ship are a major contributor to unnecessary work content growth later in Detail Design and Construction (DD&C) that cannot be eliminated no matter how productive the shipbuilder. However, new ship design methods are being developed and integrated with legacy physics-based design and analysis tools into a Rapid Ship Design Environment (RSDE)that will enable a more rational process for initially sizing ships. The authors also identify the need for early stage design measures of complexity and ship costing tools that are more sensitive to these measures, and proposed solutions that will aid decision-makers in reducing DD&C work content by making cost-effective design decisions in early stage naval ship design.


2012 ◽  
Author(s):  
Robert G. Keane

The Navy has experimented with many ways to improve the producibility of naval ship designs. In terms of effectiveness - does the ship do what it is supposed to do - the Navy has been reasonably successful. However, in terms of efficiency - are the ships efficient to produce and own - there is still much room for improvement. Design for producibility – being able to efficiently produce a warship - must start during the earliest stages of concept design and continue to be addressed during the subsequent pre-production processes. However, many early stage naval ship design engineers either do not recognize this need or do not know how to design for producibility. A number of improvements to early stage ship design capabilities are being developed in order to make the process both effective and efficient. This paper addresses the critical stage of the collaborative Design-Build-Own process of initially sizing the hull during concept design. The author proposes the development and use of more physics-based design tools during concept design, such as those being developed under the DoD High Performance Computing Modernization Program’s Computational Research & Engineering for Acquisition Tools & Environments (CREATE) – SHIPS Project. These new ship design methodologies will enable conceptual design engineers to adequately size a ship to meet military performance requirements and to have a low enough ship density to ensure successful ship construction outcomes. The director of a Netherlands’ shipyard which designs and builds surface combatants recently stated at a luncheon of the American Society of Naval Engineers (ASNE), “We learned a long time ago to give ourselves enough space to build a ship – steel is cheap, air is free!”


2016 ◽  
Vol 32 (02) ◽  
pp. 110-123
Author(s):  
Robert G. Keane ◽  
Laurent Deschamps ◽  
Steve Maguire

The Office of the Under Secretary of Defense, Acquisition, Technology, and Logistics (AT&L) recently presented analyses of cost and schedule growth on Major Defense Acquisition Programs (MDAPs) over the last 20 years (2013, 2014). For naval ships, AT&L (2013) concluded that contract work content growth (not capability growth) dominates total cost growth statistically. In addition, costs-over-target are significant and reflect poor cost estimation or faulty framing assumptions. AT&L (2014) also concluded prices on fixed-price contracts are only "fixed" if the contractual work content remains fixed, but this is often not the case. We show that under-sizing the ship during concept design studies increases ship outfit density and adds complexities to the design. These early-stage design decisions on sizing the ship are a major contributor to unnecessary work content growth later in Detail Design and Construction (DD&C) that cannot be eliminated no matter how productive the shipbuilder. However, new ship design methods are being developed and integrated with legacy physicsbased design and analysis tools into a Rapid Ship Design Environment (RSDE) that will enable a more rational process for initially sizing ships. We also identify the need for early-stage design measures of complexity and ship costing tools that are more sensitive to these measures, and propose solutions that will aid decision-makers in reducing DD&C work content by making cost-effective design decisions in early-stage naval ship design.


2021 ◽  
Vol 225 ◽  
pp. 108731
Author(s):  
Luke C. Brownlow ◽  
Conner J. Goodrum ◽  
Michael J. Sypniewski ◽  
James A. Coller ◽  
David J. Singer

2008 ◽  
Author(s):  
R. Keane ◽  
H. Fireman ◽  
J. Hough ◽  
D. Helgerson ◽  
C. Whitcomb

Last year, the Naval Sea Systems Command (NAVSEA) sponsored the Navy’s Center for Innovation in Ship Design (CISD) to establish a framework for developing ship design capability readiness levels as part of a business case to provide incentives for the naval ship enterprise to invest in developing, sustaining and improving mature naval ship design capabilities. The authors describe the accomplishments thus far and note that there is now enough documentation that new ship acquisition programs can specify design readiness requirements and have valid criteria for evaluating the design capabilities of contractors proposing to perform early stage naval ship design. They actually apply the framework to NAVSEA and assess NAVSEA’s readiness to design a naval ship. Although significant progress is being made on developing Ship Design Capability Readiness Models (SDCRM), much work remains to be done!


2009 ◽  
Vol 25 (01) ◽  
pp. 45-58
Author(s):  
R. Keane ◽  
H. Fireman ◽  
J. Hough ◽  
D. Helgerson ◽  
C. Whitcomb

Last year, the Naval Sea Systems Command (NAVSEA) sponsored the Navy’s Center for Innovation in Ship Design (CISD) to establish a framework for developing ship design capability readiness levels as part of a business case to provide incentives for the naval ship enterprise to invest in developing, sustaining, and improving mature naval ship design capabilities. The authors describe the accomplishments thus far and note that there is now enough documentation that new ship acquisition programs can specify design readiness requirements and have valid criteria for evaluating the design capabilities of contractors proposing to perform early stage naval ship design. They actually apply the framework to NAVSEA and assess NAVSEA's readiness to design a naval ship. Although significant progress is being made on developing Ship Design Capability Readiness Models (SDCRM), much work remains to be done!


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