Active Noise Cancellation For The Cabin
Elliott Aviation last month announced a partnership with Rosen Aviation to provide a combination Sound Management System (SMS) cabin-noise-cancelling system and in-flight entertainment system for King Air 200-, 300- and 350-series aircraft. Elliott's SMS is a cabin-space noise-cancellation system that dampens noise levels throughout the cabin using strategically placed speakers to counter the undesirable noise generated by propeller blade shock waves directed at the fuselage. The system adds just under 80 pounds to an aircraft and it takes two weeks to install the various sensors, speakers, microphones and other hardware. Rosen Aviation's RosenView VX cabin DVD entertainment system adds only 3.5 pounds, plus the versatility of independent entertainment flexibility for passengers. For more information, contact Mark Wilken at (800)447-6711.
Full cabin active noise cancellation is not entirely new. Once upon a time, a UK group called Ultra Electronics, Noise and Vibration Systems developed a successful active noise-control system for the aircraft cabin environment of Bombardier Q400 turboprop aircraft (see the research here). The key to the equation is targeting model-specific propeller-generated pressure waves that transmit vibration into the aircraft structure and into the cabin. To do that, Ultra Electronics developed a system for Bombardier Q400 aircraft that introduces an array of sensors, actuators and amplifiers that ultimately generates a secondary acoustic vibration field into the cabin to counteract the effect of the prop pulses. The fully active system incorporates acoustical measurements and data analysis, and reduces noise to levels competitive with regional jets.