The Boeing Company

Northrop Grumman Systems Corporation

Ronald F Olsen

Marlin D Breer

Brian L Riedel

Robert K Kunze, Jr

Charles A Parente

Noe Arcas

Belur N Shivashankara

Kevin A Burnside

Fredrick M Hutto

William H Herkes

Jeffrey M Orzechowski

A method for monitoring airplane noise and emissions may include receiving a predetermined set of engine performance data for an airplane and receiving a predetermined set of airplane flight data for the airplane. The method may also include predicting at least one of a noise level and an emissions level from the airplane at each of a plurality of ground based noise and emissions monitoring stations based on the predetermined set of engine performance data and the predetermined set of airplane flight data. Each of the plurality of ground based noise and emissions monitoring stations is located at a predetermined geographic location along an expected flight path of the airplane. The method may also include presenting at least one of the predicted noise level and the predicted emissions level on a display to a pilot of the airplane to permit operation of the airplane to substantially minimize at least one of an actual noise level and an actual emissions level at each of the plurality of ground based noise and emissions monitoring stations.

Onboard airplane community noise and emissions monitor

Flow restrictors for aircraft inlet acoustic cores, and associated systems and methods are disclosed. A system in accordance with one embodiment of the invention includes an inlet flow surface having multiple openings, and an acoustic treatment positioned adjacent to the inlet flow surface. The acoustic treatment can have multiple cells in fluid communication with the openings in the inlet flow surface. A fluid collector passage can be positioned to collect liquid entering the acoustic treatment through the multiple openings, and can have an exit aperture through which the liquid drains. The fluid collector passage can include at least one flow restrictor positioned to at least restrict the flow of air from the exit aperture through the fluid collector passage to the multiple openings.

Flow restrictors for aircraft inlet acoustic treatments, and associated systems and methods

An inlet ice protection system, and methods for making and using ice protection systems. In one embodiment, the inlet includes a tapered acoustic liner positioned forward of the inlet throat and has a perforated face sheet, a perforated back sheet, and an acoustic core between the face sheet and the back sheet. The perforations through the face sheet are sized to allow acoustic energy to be transmitted to and dissipated in the acoustic core, and the perforations in the back sheet are sized to transmit hot gas through the acoustic liner to the surface of the inlet to heat the inlet and prevent and/or restrict ice formation on the inlet. The face sheet can have a higher porosity than the back sheet, and both the sheets and the core can be formed from titanium to withstand high gas temperatures.

Method and apparatus for aircraft inlet ice protection

An inlet ice protection system, and methods for making and using ice protection systems. In one embodiment, the inlet includes an acoustic liner positioned forward of the inlet throat and has a perforated face sheet, a perforated back sheet, and an acoustic core between the face sheet and the back sheet. The perforations through the face sheet are sized to allow acoustic energy to be transmitted to and dissipated in the acoustic core, and the perforations in the back sheet are sized to transmit hot gas through the acoustic liner to the surface of the inlet to heat the inlet and prevent and/or restrict ice formation on the inlet. The face sheet can have a higher porosity than the back sheet, and both the sheets and the core can be formed from titanium to withstand high gas temperatures.

An inlet ice protection system, and methods for making and using ice protection systems. In one embodiment, the inlet includes an acoustic liner positioned forward of the inlet throat and has a perforated face sheet a perforated back sheet, and an acoustic core between the face sheet and the back sheet. The perforations through the face sheet are sized to allow acoustic energy to be transmitted to and dissipated in the acoustic core, and the perforations in the back sheet are sized to transmit hot gas through the acoustic liner to the surface of the inlet to heat the inlet and prevent and/or restrict ice formation on the inlet. The face sheet can have a higher porosity than the back sheet, and both the sheets and the core can be formed from titanium to withstand high gas temperatures.

A device for measuring the acoustic absorption properties of materials such as liners for jet engines has a first housing, an acoustic driver configured to provide acoustic energy to the first housing, a second housing attached to the first housing, and an acoustic driver configured to provide acoustic energy to the second housing. Acoustic sensors are used to measure the acoustic energy emitted from the two housings and to measure the absorption of each of the housings.

Apparatus and method for measuring the acoustic properties of acoustic

A jet engine fan noise reduction system. The noise reduction system includes active noise control to suppress fan tone noise of an airplane flyover noise signature. The active noise control includes microphones with acoustic transducers upstream and downstream of the engine fan and fan exit guide vane stage to sense control system errors. Control signals are derived from the fan angular speed or blade passing frequency and the error signals sensed by the acoustic transducers. The control output signals actuate (modulate) air control valves on each side of the fan stage to direct conditioned (pressure and temperature regulated) high pressure primary air flow, thereby producing acoustic canceling of fan tone noise.

Growing community of inventors

Woodinville, WA, United States of America

Ronald F Olsen