TECHNOLOGY TRANSFER OPPORTUNITY: Multirotor Aircraft Noise Reduction (LAR-TOPS-325)

NASA’s Technology Transfer Program solicits inquiries from companies interested in obtaining license rights to commercialize, manufacture and market the following technology. License rights may be issued on an exclusive or nonexclusive basis and may include specific fields of use. NASA provides no funding in conjunction with these potential licenses.THE TECHNOLOGY:Multirotor aircraft typically create a significant amount of tonal noise from each rotor. Groups of rotors operating at the same rotation rate with an appropriate phase offset can be used to reduce the tonal noise of the aircraft when there are multiple rotors on each side of the aircraft. Reducing tonal noise, depending on the aircraft design, can effectively reduce the total noise output for a given flight scenario. Aircraft can be designed with this technology to prioritize quieter take-off and landing, or can be designed for decreased noise in cruise. Existing designs may benefit from this technology as well, but what

type of benefits can be gained depend on the design of the aircraft. Using this method, multiple rotors can be significantly quieter than a single rotor, without sacrificing thrust.Noise produced by multirotor vehicles may be objectionable to some, especially as industry moves toward drone deliveries and potentially air taxi operations. However, noise reductions can now be attained by synchronizing the rotation rate and then controlling the phase offset between neighboring rotors. The optimal phase offset is uniquely defined based on the number of blades and the relative location of each rotor and does not depend on the rotation rate, blade geometry, or other aspects of the vehicle design. This technology is not viable for all multirotor aircraft but is applicable if the rotation rate of neighboring rotors can be synchronized mechanically or electronically.To express interest in this opportunity, please submit a license application through NASA’s Automated Technology Licensing Application System (ATLAS) by visiting https://technology.nasa.gov/patent/LAR-TOPS-325If you have any questions, please e-mail NASA’s Technology Transfer Program at Agency-Patent-Licensing@mail.nasa.gov with the title of this Technology Transfer Opportunity as listed in this SAM.gov notice and your preferred contact information. For more information about licensing other NASA-developed technologies, please visit the NASA Technology Transfer Portal at https://technology.nasa.gov/These responses are provided to members of NASA’s Technology Transfer Program for the purpose of promoting public awareness of NASA-developed technology products, and conducting preliminary market research to determine public interest in and potential for future licensing opportunities. No follow-on procurement is expected to result from responses to this Notice.