Imagine a silent helicopter stealthily moving troops and supplies around a future battlefield. U.S. Army researchers look to helicopter noise reduction technology as a top priority in aircraft design.
At the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory, researchers collaborated with Uber and the University of Texas at Austin to investigate the acoustic properties of electric vertical takeoff and landing aircraft, which use distributed electric propulsion to power flight.
These eVTOL vehicles may aid the Army with important tasks such as aerial surveillance and cargo transport; however, they feature smaller rotors than traditional helicopters. As a result, eVTOL rotors may emit a different sound signature that researchers will have to take into consideration.
“The noise you hear from these smaller rotors is generated through fundamentally different physical mechanisms,” said Dr. George Jacobellis, Army research engineer at the laboratory’s Vehicle Technology Directorate. “Traditional modeling techniques