Quiet Planes Make Good Neighbors

Dean Sigler Electric Powerplants, Sustainable Aviation 1 Comment

With this year’s Electric Aircraft Symposium just a few days away, the next few blog entries will close out reviews of presentations from EAS V. Krish J. Ahuja, Regents Professor at the School of Aerospace Engineering and the head of the Aerospace and Acoustics Technology Division at Georgia Institute of Technology, talked on “Quiet Propulsion for Small Electric Aircraft.” Dr. Ahuja came with great credentials, including his 1993 AIAA Aeroacoustics Award and being listed as one of top 50 Innovators by Aerospace magazine, 1995 and one of top 50 Technology leaders in the US by Industry Week Magazine. He started by examining the sources of aircraft noise.  Internal combustion engines (ICEs) are inherently noisy, but propellers add to that noise by their thickness, speed of rotation and the amount of loading they bear in producing thrust.  Converting air from low to high pressure as it moves through the propeller’s blades generates noise. Most annoying, the rasping shriek that comes from …