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This paper presents results of active structural acoustic control (ASAC) and active noise control (ANC) tests conducted to reduce broadband sound transmission in an aircraft fuselage, as an important step toward the design and development of a system for aircraft applications. The broadband active control tests were conducted in the furnished aft cabin of a DC-9 fuselage section housed in a large anechoic room in the Fuselage Acoustics Research Facility (FARF) at McDonnell Douglas, Long Beach, CA. Transfer functions between each actuator (on fuselage panels) and representative interior microphones were predicted using a finite element model of the fuselage, assuming that actuators can be placed on every panel of the fuselage. The analytical transfer function data were used to select actuator locations that provided the best simulated noise reduction at the interior microphone locations. Experiments were conducted to collect actual transfer functions between the eighteen microphone sensors and both the exterior disturbance (loudspeaker) source and sixty four control (PZT) sources. The experimental transfer function data were used to select optimum locations for the piezoelectric actuators, to optimize the multichannel controller, and to simulate broadband ASAC. Finally, broadband ASAC and ANC demonstration tests were conducted on the DC-9 fuselage.

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