# US 12,180,845 B1 · Aircraft duct assembly and sealing structure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,845 B1 - Document ID: US12180845B1 - Status: Granted - Kind: B1 - Application number: 18/330,540 - Filed: 2023-06-07 - Published: 2024-12-12 - Granted: 2024-12-31 - Earliest claimed: 2023-06-07 - Assignees: Spirit AeroSystems, Inc. - Applicants: Spirit AeroSystems, Inc. - Inventors: Roger Edmund Kornfeld - Web page: https://patentgrep.com/patent/US12180845B1 ## CPC - B64D 29/02: associated with wings - F01D 11/08: for sealing space between rotor blade tips and stator (specially-shaped blade tips therefor F01D5/20) - B64D 29/00: Power-plant nacelles, fairings or cowlings - F02C 7/28: Arrangement of seals - F02K 1/805: {Sealing devices therefor, e.g. for movable parts of jet pipes or nozzle flaps} - F01D 9/041: {using blades (F01D5/148 takes precedence)} - F01D 11/005: {Sealing means between non relatively rotating elements} - F01D 17/162: {for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line (F01D17/167 takes precedence)} - F01D 25/28: Supporting or mounting arrangements, e.g. for turbine casing - F05D 2230/51: in a modular way, e.g. using several identical or complementary parts or features - F05D 2230/54: by sheet metal manufacturing - F05D 2240/55: Seals - F05D 2300/431: Rubber - F05D 2300/437: Silicon polymers - F05D 2300/603: Composites; e.g. fibre-reinforced - F05D 2300/612: Foam - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A sealing structure seals a space between first and second parts of a fan duct and a fairing of an aircraft engine. The sealing structure comprises first and second seal portions for positioning between the first and second parts of the fan duct and the fairing. The first seal portion includes an elongated middle region and a first coupling mechanism. The elongated middle region can be secured to the first part of the fan duct and abutting the fairing and includes a forward end from which the first coupling mechanism extends. The second seal portion includes an elongated middle region and a second coupling mechanism. The elongated middle region can be secured to the second part of the fan duct and abutting the fairing and includes a forward end from which the second coupling mechanism extends. The second coupling mechanism is operable to couple to the first coupling mechanism. ## Claims ### Claim 1 A sealing structure for sealing a space between first and second parts of a fan duct and a fairing of an aircraft engine, the sealing structure comprising: a first seal portion for positioning between the fairing and the first part of the fan duct, the first seal portion comprising: an elongated middle region for securing to the first part of the fan duct and abutting the fairing, the elongated middle region including a forward end, and a first coupling mechanism extending from the forward end; and a second seal portion for positioning between the fairing and the second part of the fan duct, the second seal portion comprising: an elongated middle region for securing to the second part of the fan duct and abutting the fairing, the elongated middle region including a forward end, and a second coupling mechanism extending from the forward end and operable to couple to the first coupling mechanism; wherein the first seal portion and the second seal portion are attached to the first and second parts of the fan duct such that when the first and second parts of the fan duct are brought together to close the fan duct on the fairing, the second coupling mechanism engages the first coupling mechanism to temporarily couple to the first coupling mechanism and the first seal portion and the second seal portion deform against an outer perimeter of the fairing to seal the space between the first and second parts of the fan duct and the fairing. ### Claim 2 (depends on 1) The sealing structure of claim 1, wherein the first coupling mechanism comprises a cavity, and the second coupling mechanism comprises an insert that fits within the cavity of the first coupling mechanism. ### Claim 3 (depends on 2) The sealing structure of claim 2, wherein the cavity comprises a groove that extends along the forward end of the first seal portion, and the insert comprises a tab that is complementary to at least a portion of the groove. ### Claim 4 (depends on 1) The sealing structure of claim 1, wherein— the first seal portion comprises: an aft fairing block extending from an aft end of the elongated middle region of the first seal portion and comprising compressible material, and a forward transition block extending from the forward end of the elongated middle region of the first seal portion and comprising compressible material; and the second seal portion comprises: an aft fairing block extending from an aft end of the elongated middle region of the second seal portion and including compressible material, and a forward transition block extending from the forward end of the elongated middle region of the second seal portion and comprising compressible material. ### Claim 5 (depends on 4) The sealing structure of claim 4, wherein the compressible material of the aft fairing block of at least one of the first seal portion or the second seal portion comprises foam encased in reinforced silicone. ### Claim 6 (depends on 1) The sealing structure of claim 1, wherein the elongated middle region of at least one of the first seal portion or the second seal portion comprises: a tab portion for securing to the first part of the fan duct, and a flexible center blade extending at an angle relative to the tab portion for abutting the fairing. ### Claim 7 (depends on 1) The sealing structure of claim 1, wherein the first seal portion comprises: a forward blade portion extending from the first coupling mechanism and including an aft end connected to the first coupling mechanism and a forward end opposite to the aft end, and a forward duct block extending from the forward end of the forward blade portion and comprising compressible material. ### Claim 8 (depends on 7) The sealing structure of claim 7, wherein the forward blade portion comprises reinforced silicone, and the compressible material comprises foam encased in reinforced silicone. ### Claim 9 (depends on 1) The sealing structure of claim 1, wherein the middle region of the first seal portion includes an aft end, wherein the first seal portion comprises: an aft blade portion extending from the aft end of the middle region of the first seal portion and including a proximal end connected to the aft end of the middle region of the first seal portion and a distal end opposite to the proximal end, and an aft duct block extending from the distal end of the aft blade portion and comprising compressible material. ### Claim 10 (depends on 9) The sealing structure of claim 9, wherein the aft blade portion comprises reinforced silicone, and the compressible material comprises foam encased in reinforced silicone. ### Claim 11 An aircraft duct assembly for an engine having an engine fairing, the aircraft duct assembly comprising: a first duct wall comprising: a first forward edge, a first aft edge opposite the first forward edge, and a first duct interface extending from the first forward edge to the first aft edge and having a first recess that defines a portion of a cavity for receiving the engine fairing; a second duct wall for cooperatively enclosing at least a portion of the engine with the first duct wall, the second duct wall comprising: a second forward edge, a second aft edge opposite the second forward edge, and a second duct interface extending from the second forward edge to the second aft edge and having a second recess that defines a portion of the cavity for receiving the engine fairing; and a sealing structure for sealing a space between the engine fairing and the first duct wall and the second duct wall, the sealing structure comprising: a first seal portion secured to at least a portion of the first duct interface, the first seal portion comprising a forward end with a first coupling mechanism, and a second seal portion secured to at least a portion of the second duct interface, the second seal portion comprising a forward end with a second coupling mechanism that couples to the first coupling mechanism. ### Claim 12 (depends on 11) The aircraft duct assembly of claim 11, wherein the first coupling mechanism comprises a cavity, and the second coupling mechanism comprises an insert that fits within the cavity of the first coupling mechanism. ### Claim 13 (depends on 11) The aircraft duct assembly of claim 11, wherein: the first seal portion comprises: a first tab portion for securing to the first recess of the first duct interface and comprising reinforced silicone, and a first flexible center blade extending at an angle relative to the first tab portion for abutting the engine fairing and comprising pre-preg; and the second seal portion comprises: a second tab portion for securing to the second recess of the second duct interface and comprising reinforced silicone, and a second flexible center blade extending at an angle relative to the second tab portion for abutting the engine fairing and comprising pre-preg. ### Claim 14 (depends on 11) The aircraft duct assembly of claim 11, wherein the first seal portion further comprises: a forward blade portion extending between the first forward edge and the first recess on the first duct interface; a forward duct block extending from the forward blade portion proximate to the first forward edge and comprising compressible material; an aft blade portion extending between the first aft edge and the first recess on the first duct interface; and an aft duct block extending from the aft blade portion proximate to the first aft edge and comprising compressible material. ### Claim 15 A sealing structure for sealing a space between first and second parts of a fan duct and a fairing of an aircraft engine, the sealing structure comprising: a first seal portion for positioning between the fairing and the first part of the fan duct, the first seal portion comprising: an elongated middle region including a tab portion for securing to the first part of the fan duct and a flexible center blade extending at an angle relative to the tab portion for abutting the fairing, an aft fairing block extending from the middle region and comprising compressible material, and a forward transition block extending from the elongated middle region opposite to the aft fairing block and including compressible material, and a first coupling mechanism connected to the forward transition block; and a second seal portion for positioning between the fairing and the second part of the fan duct, the second seal portion comprising an elongated middle region including a tab portion for securing to the second part of the fan duct and a flexible center blade extending at an angle relative to the tab portion for abutting the fairing, an aft fairing block extending from the middle region and operable to abut the aft fairing block of the first seal portion, and a forward transition block extending from the elongated middle region opposite to the aft fairing block, and a second coupling mechanism that is operable to couple to the first coupling mechanism. ### Claim 16 (depends on 15) The sealing structure of claim 15, wherein the center blade of at least one of the first seal portion or the second seal portion comprises pre-preg. ### Claim 17 (depends on 16) The sealing structure of claim 16, wherein the tab portion of at least one of the first seal portion or the second seal portion comprises reinforced silicone. ### Claim 18 (depends on 15) The sealing structure of claim 15, wherein the first seal portion further comprises: a forward blade portion extending from the forward transition block and having an aft end connected to the forward transition block and a forward end opposite to the aft end; a forward duct block extending from the forward end of the forward blade portion and comprising compressible material; an aft blade portion extending from the aft fairing block and having a forward end connected to the aft fairing block and an aft end opposite to the forward end; and an aft duct block extending from the aft end of the aft blade portion and comprising compressible material. ### Claim 19 (depends on 15) The sealing structure of claim 15, wherein the first coupling mechanism comprises a cavity, and the second coupling mechanism comprises an insert that fits within the cavity of the first coupling mechanism. ### Claim 20 (depends on 15) The sealing structure of claim 15, wherein the center blade of the first seal portion is angled relative to the tab portion to cover the space between the first part of the fan duct and the fairing.