Very Low Noise, High Efficiency Propeller Designs for Small UAVs

"The proposed SBIR program offers a unique opportunity to use design and fabrication technology developed in recent government and industry funded programs to design a low-cost, high-performance, light-weight, low-noise propeller for Small UAV's. Global Aircraft Corp.(GAC) has the technology to design and manufacture composite propellers with scimitar shaped blades that flex to change pitch. This ability to flex allows the propeller to provide high performance over a wide range of operatingconditions. This technology was developed under NASA SBIR and NASA AGATE funding. The design process has been recently automated using a rules-based computer program that performs finite analysis of blade geometry to show the effect of operatingcondition on blade deflection and vibratory modes that must be addressed in a structurally sound propeller design. The objective of the proposed SBIR Phase I project is to design, fabricate, and test proof-of-concept propellers that produce 12 dB less noise than commercially available hobby industry 2-blade propellers. The Phase II work is to further reduce the noise of the propeller developed in Phase I by 8 or more dB while maintaining performance within 5% of the Phase I design. The proposed SBIR project will increase the knowledge base concerning the design of low-noise, high-efficiency propellers for small UAVs. This knowledge can be applied to the design of propellers for numerous military an