Process and apparatus for noise reduction in multi-engine propeller-driven aircraft
Patent 6896219 Issued on May 24, 2005. Estimated Expiration Date: 
March 19, 2023. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 19, 2023. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 4900226 Propeller blade position controller Adaptive synchrophaser for reducing aircraft cabin noise and vibration Method for reducing noise and/or vibration from multiple rotating machines Patent #: 5789678 InventorsAssigneeApplicationNo. 10391181 filed on 03/19/2003US Classes:244/1N, Noise abatement244/13, Airplane sustained415/119, WITH SOUND OR VIBRATORY WAVE ABSORBING OR PREVENTING MEANS OR ARRANGEMENT181/206By wave interferenceExaminersPrimary: Swiatek, Robert P.Attorney, Agent or FirmInternational ClassB64C011/50AbstractA process and system for noise reduction in multi-engine propeller-driven aircraft. The parameters of at least two propellers are adjusted with regard to frequency, amplitude, and phase so that the sound fields of the propellers are attenuated or completely extinguished by interference in the area of the closest aircraft fuselage. | |
