# US 2014/0151150 A1 · Monolithic acoustically-treated composite structures and methods for fabricating the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0151150 A1 - Document ID: US20140151150A1 - Status: Published application - Kind: A1 - Application number: 14/174,480 - Filed: 2014-02-06 - Published: 2014-06-05 - Earliest claimed: 2012-02-20 - Assignees: Honeywell International Inc. - Applicants: Honeywell International Inc. - Inventors: Adam Kowal; Jeffrey Hein; David E. Wilcox - Web page: https://patentgrep.com/patent/US20140151150A1 ## CPC - B64C 1/40: Sound or heat insulation {, e.g. using insulation blankets} - B64D 41/00: Power installations for auxiliary purposes - B64D 2033/0206: {comprising noise reduction means, e.g. acoustic liners} - B64D 2033/0213: {specially adapted for auxiliary power units (APU's)} - Y02T 50/40: Weight reduction - Y10T 156/10: Methods of surface bonding and/or assembly therefor - B64C: AEROPLANES; HELICOPTERS - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Monolithic acoustically-treated composite structures and methods for fabricating the same are provided. A monolithic acoustically-treated composite structure comprises an internal frame assembly comprising a unitary composite frame structure and at least one acoustic panel assembly. The unitary composite frame structure defines a shape of the monolithic acoustically-treated composite structure to be fabricated. A composite overlay covers the internal frame assembly. The method for fabricating the monolithic acoustically-treated composite structure comprises forming the unitary composite frame structure, including the at least one acoustic panel in the unitary composite frame structure, and covering the internal frame assembly with the composite overlay. ## Claims ### Claim 1 A monolithic acoustically-treated composite structure comprising: an internal frame assembly comprising a unitary composite frame structure and at least one acoustic panel assembly included in the unitary composite frame structure, the unitary composite frame structure defining a shape of the monolithic acoustically-treated composite structure; and a composite overlay covering the internal frame assembly. ### Claim 2 (depends on 1) The monolithic acoustically-treated composite structure of claim 1, wherein the internal frame assembly defines an interior surface, the interior surface having a contoured or planar configuration which is substantially free of surface discontinuities. ### Claim 3 (depends on 1) The monolithic acoustically-treated composite structure of claim 1, wherein the unitary composite frame structure comprises a plurality of interconnected frame members that cooperate to define at least one side opening in the unitary composite frame structure, an acoustic panel assembly of the at least one acoustic panel assembly extending across a side opening of the at least one side opening to complete a side panel of the internal frame assembly. ### Claim 4 (depends on 3) The monolithic acoustically-treated composite structure of claim 3, wherein the acoustic panel assembly comprises: an acoustic core comprising a plurality of cells having a first end and a second end; and a perforated acoustic facesheet having a front surface including a peripheral border portion surrounding an interior portion, a rear surface bonded to the first end of the acoustic core, and a plurality of spaced perforations. ### Claim 5 (depends on 4) The monolithic acoustically-treated composite structure of claim 4, wherein each side opening is surrounded by a perimeter mounting surface for mounting the peripheral border portion thereto, the acoustic core extending outwardly and rearwardly from the rear surface of the perforated acoustic facesheet. ### Claim 6 (depends on 5) The monolithic acoustically-treated composite structure of claim 5, wherein the plurality of interconnected frame members comprises a plurality of side frame members extending between upper and lower frame members, each side frame member of the plurality of side frame members comprising a pair of narrow side flanges, each narrow side flange of the pair of narrow side flanges extending along a side edge of a respective side opening and a side edge of a respective adjacent side opening and the upper and lower frame members each comprising a narrow flange portion that extends respectively along a top edge and a bottom edge of each side opening, the narrow flange portion of each of the upper and lower frame members and a narrow side flange of the pair of narrow side flanges of a pair of side frame members cooperating to form the perimeter mounting surface surrounding each side opening. ### Claim 7 (depends on 6) The monolithic acoustically-treated composite structure of claim 6, wherein the perimeter mounting surface defines an open relief pocket for the acoustic panel assembly. ### Claim 8 (depends on 1) The monolithic acoustically-treated composite structure of claim 1, wherein each acoustic panel assembly included in the unitary composite frame structure forms an acoustically-treated area of the monolithic acoustically-treated composite structure. ### Claim 9 A monolithic acoustically-treated composite structure comprising: a unitary composite frame structure; at least one acoustic panel assembly included in the unitary composite frame structure forming an internal frame assembly, each acoustic panel assembly comprising an acoustic core and a perforated acoustic facesheet, the perforated acoustic facesheet having an interior portion that forms an interior surface portion of the monolithic acoustically-treated composite structure; and a composite overlay covering the internal frame assembly. ### Claim 10 (depends on 9) The monolithic acoustically-treated composite structure of claim 9, wherein the internal frame assembly defines an interior surface comprising the interior surface portion, the interior surface having a contoured or planar configuration which is substantially free of surface discontinuities. ### Claim 11 (depends on 9) The monolithic acoustically-treated composite structure of claim 9, wherein the unitary composite frame structure comprises a plurality of interconnected frame members that cooperate to define at least one side opening in the unitary composite frame structure, an acoustic panel assembly of the at least one acoustic panel assembly extending across a side opening of the at least one side opening to complete a side panel of the internal frame assembly. ### Claim 12 (depends on 11) The monolithic acoustically-treated composite structure of claim 11, wherein the acoustic panel assembly comprises: the acoustic core comprising a plurality of cells having a first end and a second end; and the perforated acoustic facesheet having a front surface including a peripheral border portion surrounding the interior portion, a rear surface bonded to the first end of the acoustic core, and a plurality of spaced perforations. ### Claim 13 (depends on 12) The monolithic acoustically-treated composite structure of claim 12, wherein each side opening is surrounded by a perimeter mounting surface for mounting the peripheral border portion thereto, the acoustic core extending outwardly and rearwardly from the rear surface of the perforated acoustic facesheet. ### Claim 14 (depends on 13) The monolithic acoustically-treated composite structure of claim 13, wherein the plurality of interconnected frame members comprises a plurality of side frame members extending between upper and lower frame members, each side frame member of the plurality of side frame members comprising a pair of narrow side flanges, each narrow side flange of the pair of narrow side flanges extending along a side edge of a respective side opening and a side edge of a respective adjacent side opening and the upper and lower frame members each comprising a narrow flange portion that extends respectively along a top edge and a bottom edge of each side opening, the narrow flange portion of each of the upper and lower frame members and a narrow side flange of the pair of narrow side flanges of a pair of side frame members cooperating to form the perimeter mounting surface surrounding each side opening. ### Claim 15 (depends on 14) The monolithic acoustically-treated composite structure of claim 14, wherein the perimeter mounting surface defines an open relief pocket for the acoustic panel assembly. ### Claim 16 (depends on 9) The monolithic acoustically-treated composite structure of claim 9, wherein each acoustic panel assembly included in the unitary composite frame structure forms an acoustically-treated area of the monolithic acoustically-treated composite structure.