Public reporting burden for this collection of information is estimated to average 1 hour per response, including g the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of the collection of information, including suggestions for reducing this burden to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503. AGENCY USE ONLY (Leave blank)2. REPORT DATE 6 May 2005 REPORT TYPE AND DATE COVERED TITLE AND SUBTITLEAnalysis, fabrication, and testing of a composite bladed propeller for a Naval Academy Yard Patrol (YP) craft AUTHOR(S) Wozniak, Christopher D. (Christopher David), 1982- FUNDING NUMBERS PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)8. PERFORMING ORGANIZATION REPORT NUMBER SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING AGENCY REPORT NUMBER US Naval Academy Annapolis, MD 21402Trident Scholar project report no. (2005) SUPPLEMENTARY NOTES 12a. DISTRIBUTION/AVAILABILITY STATEMENTThis document has been approved for public release; its distribution is UNLIMITED. 12b. DISTRIBUTION CODE ABSTRACT:The U.S. Navy, and much of the maritime industry, uses nickel-aluminum-bronze (NAB) as the primary material for propeller construction. This is done for many reasons, including its anti-biofouling characteristics, high stiffness, and low corrosion potential. However, NAB is a cathodic metal. While it experiences little corrosion itself, its presence leads to galvanic corrosion of the surrounding hull steel. The U.S. Navy, and much of the maritime industry, uses nickel-aluminum-bronze (NAB) as the primary material for propeller construction. This is done for many reasons, including its anti-biofouling characteristics, high stiffness, and low corrosion potential. However, NAB is a cathodic metal. While it experiences little corrosion itself, its presence leads to galvanic corrosion of the surrounding hull steel. The Navy has considered the feasibility of a composite bladed propeller design, but several variables need investigation. The goal of this Trident project was to design, build and test the Navy's first composite propeller. The detailed objectives of the research were to: evaluate a hub design; perform a structural design of a Yard Patrol (YP) craft composite bladed propeller; and finally, build and test a full-scale propeller using the composite materials. As the general concept used composite blades attached to a NAB hub, the first step was to develop a design for the hub-blade interaction. Afterwards, the loads were predicted using computational fluid dynamics. The pressure plot was then combined with the geometry in a finite element structural analysis program to determine fiber orientation and strengt...