Thomas R Brooks

US Patent:

7484930, Feb 3, 2009

Filed:

Jun 22, 2005

Appl. No.:

11/169256

Inventors:

Florence V. Hutcheson - Virginia Beach VA, US
Thomas F. Brooks - Seaford VA, US

Assignee:

The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Washington DC

International Classification:

B64C 23/00

US Classification:

415119, 416231 B

Abstract:

A reduction in noise radiating from a side of a deployed aircraft flap is achieved by locating a slot adjacent the side of the flap, and then forcing air out through the slot with a suitable mechanism. One, two or even three or more slots are possible, where the slot is located at one or more locations selected from a group of locations comprising a top surface of the flap, a bottom surface of the flap, an intersection of the top and side surface of the flap, an intersection of the bottom and side surfaces of the flap, and a side surface of the flap. In at least one embodiment the slot is substantially rectangular. A device for adjusting a rate of the air forced out through the slot can also be provided.

US Patent:

7783060, Aug 24, 2010

Filed:

May 10, 2005

Appl. No.:

11/126518

Inventors:

Thomas F. Brooks - Seaford VA, US

Assignee:

The United States of America as represented by the Administrator of the National Aeronautics and Space Administration - Washington DC

International Classification:

H04R 3/00

US Classification:

381 92, 381 91, 381122, 367118, 367119

Abstract:

A method and system for mapping acoustic sources determined from a phased microphone array. A plurality of microphones are arranged in an optimized grid pattern including a plurality of grid locations thereof. A linear configuration of N equations and N unknowns can be formed by accounting for a reciprocal influence of one or more beamforming characteristics thereof at varying grid locations among the plurality of grid locations. A full-rank equation derived from the linear configuration of N equations and N unknowns can then be iteratively determined. A full-rank can be attained by the solution requirement of the positivity constraint equivalent to the physical assumption of statically independent noise sources at each N location. An optimized noise source distribution is then generated over an identified aeroacoustic source region associated with the phased microphone array in order to compile an output presentation thereof, thereby removing the beamforming characteristics from the resulting output presentation.

US Patent:

8170234, May 1, 2012

Filed:

Apr 24, 2008

Appl. No.:

12/108562

Inventors:

Thomas F. Brooks - Seaford VA, US

Assignee:

The United States of America by the Administrator of the National Aeronautics and Space Adminstration - Washington DC

International Classification:

H04R 3/00

US Classification:

381 92, 381 91, 381122, 367118, 367119

Abstract:

Mapping coherent/incoherent acoustic sources as determined from a phased microphone array. A linear configuration of equations and unknowns are formed by accounting for a reciprocal influence of one or more cross-beamforming characteristics thereof at varying grid locations among the plurality of grid locations. An equation derived from the linear configuration of equations and unknowns can then be iteratively determined. The equation can be attained by the solution requirement of a constraint equivalent to the physical assumption that the coherent sources have only in phase coherence. The size of the problem may then be reduced using zoning methods. An optimized noise source distribution is then generated over an identified aeroacoustic source region associated with a phased microphone array (microphones arranged in an optimized grid pattern including a plurality of grid locations) in order to compile an output presentation thereof, thereby removing beamforming characteristics from the resulting output presentation.

US Patent:

55846610, Dec 17, 1996

Filed:

Jul 6, 1995

Appl. No.:

8/498807

Inventors:

Thomas F. Brooks - Seaford VA

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

B64C 27467

US Classification:

416238

Abstract:

A forward-swept, low-noise rotor blade includes an inboard section, an aft-swept section and a forward-swept outboard section. The rotor blade reduces the noise of rotorcraft, including both standard helicopters and advanced systems such as tiltrotors. The primary noise reduction feature is the forward sweep of the planform over a large portion of the outer blade radius. The rotor blade also includes an aft-swept section. The purpose of the aft-swept region is to provide a partial balance to pitching moments produced by the outboard forward-swept portion of the blade. The rotor blade has a constant chord width; or has a chord width which decreases linearly along the entire blade span; or combines constant and decreasing chord widths, wherein the blade is of constant chord width from the blade root to a certain location on the rotor blade, then decreases linearly to the blade tip thereafter. The noise source showing maximum noise reduction is blade-vortex interaction (BVI) noise. Also reduced are thickness, noise, high speed impulsive noise, cabin vibration and loading noise.