AUVSI's Unmanned Systems 2016

Small UAS Propeller/Rotor Sound Pressure Level and Thrust Testing: Bioinspired Modifications for UAS Noise Reduction (Room Innovation Hub-- Booth 2727)

03 May 16
10:00 AM - 5:30 PM

Tracks: Academic, Air, Commercial, Defense, Research and Development

Speaker(s): Nate Callender, Associate Professor, Middle Tennessee State University

Aircraft noise is specifically addressed in Federal Aviation Regulation (FAR) Title 14 Part 36. Maximum sound pressure levels (SPL) are set by aircraft type for aircraft in phases of flight in close proximity to airports where the noise created will be most noticeable to observers on the ground. Abiding by this regulation assists in maintaining healthy relationships between the aircraft operators, airports, and local residents and businesses. With the increase of unmanned aircraft systems (UAS) in the civilian sector, perceived UAS noise may also be of concern in the near future. Exponential growth of the UAS market, fueled by affordable and easy to use systems and expected regulations, will increase UAS density in the airspace above many populated areas. In order to mitigate possible backlash, the noise levels created by small UAS must be addressed. A large portion of small UAS noise is due to propellers/rotors. The authors have undertaken to design and build apparatuses, in which to record the SPL and thrust of small UAS propellers/rotors. Small UAS propellers/rotors have been modified in order to reduce the SPL with as little effect on thrust as possible. Modifications include serrations, grooves, and fringes (motivated by the leading edge fringe designed into owl feathers) on a combination of the leading edge, trailing edge, and tips. This paper will present the SPL and thrust results for modified propellers/rotors as compared to a baseline propeller.