Access panel assembly for aircraft fuel tank

A gasket for a panel assembly particularly adapted for closing an access opening in a wall of an aircraft, where the wall has a front side, a back side, and an edge portion defining said access opening, and where said assembly comprises:

• a. a panel member having a front face and a rear face, and adapted to close said access opening, said panel member comprising a main central panel portion and a peripheral edge panel portion extending around the main central panel portion;
• b. said edge panel portion comprising an outer edge panel portion having a forward facing first outer edge panel surface portion adapted to engage a rearward facing second edge surface portion of said wall;
• c. said edge panel portion comprising an inner edge panel portion positioned inwardly of said outer edge panel portion and having a front facing third inner edge panel surface portion;
• d. a clamp ring having a front ring surface and a rear ring surface, said rear ring surface comprising an inner fourth rear ring surface portion adapted to be in bearing relationship with said third surface portion, and an outer fifth rear ring surface portion adapted to be in bearing engagement with a forward facing sixth edge surface portion of said wall;
• e. fastening means to urge said clamp ring in bearing relationship against said wall edge portion and said panel member;
• said gasket having a generally annular configuration and adapted to be positioned between said third and fourth surface portions and also between said fifth and sixth surface portions, said gasket comprising:
• a. a main central generally planar metallic electrically conductive wire mesh portion adapted to be impregnated with a lubricant and to be in metal to metal contact between the third and fourth surface portions and the fifth and sixth surface portions;
• b. an inner edge seal portion connected to, and extending along, an inner edge of said wire mesh portion, and adapted to be in sealing engagement with said third and fourth surface portions at a location inwardly of said wire mesh portion;
• c. an outer edge seal portion connected to, and extending along, an outer edge of said wire mesh portion, and adapted to be in sealing engagement with said fifth and sixth surface portions at a location outwardly of said wire mesh portion;
• whereby, when said gasket is in place in said panel assembly, an electrically conductive path is maintained between said panel member and said wall, the lubricant is retained in the gasket, and corrosion is alleviated at the third, fourth, fifth and sixth surface portion.

A method of making a gasket for a panel assembly particularly adapted for closing an access opening in a wall of an aircraft, where the wall has a front side, a back side, and an edge portion defining said access opening, said assembly comprising:

• a. a panel member having a front face and a rear face, and adapted to close said access opening, said panel member comprising a main central panel portion and a peripheral edge panel portion extending around the main central panel portion;
• b. said edge panel portion comprising an outer edge panel portion having a forward facing first outer edge panel surface portion adapted to engage a rearward facing second edge surface portion of said wall;
• c. said edge panel portion comprising an inner edge panel portion positioned inwardly of said outer edge panel portion and having a front facing third inner edge panel surface portion;
• d. a clamp ring having a front ring surface and a rear ring surface, said rear ring surface comprising an inner fourth rear ring surface portion adapted to be in bearing relationship with said third surface portion, and an outer fifth rear ring surface portion adapted to be in bearing engagement with a forward facing sixth edge surface portion of said wall;
• e. fastening means to urge said clamp ring in bearing relationship against said wall edge portion and said panel member;
• f. a gasket having a generally annular configuration and adapted to be positioned between said third and fourth surface portions and also between said fifth and sixth surface portions, said gasket comprising:
• 1. a main central generally planar metallic electrically conductive wire mesh portion adapted to be impregnated with a lubricant and to be in metal to metal contact between the third and fourth surface portions and the fifth and sixth surface portions;
• 2. an inner edge seal portion connected to, and extending along, an inner edge of said wire mesh portion, and adapted to be in sealing engagement with said third and fourth surface portions at a location inwardly of said wire mesh portion;
• 3. an outer edge seal portion connected to, and extending along, an outer edge of said wire mesh portion, and adapted to be in sealing engagement with said fifth and sixth surface portions at a location outwardly of said wire mesh portion;
• said method comprising:
• a. providing a planar piece of wire mesh material formed in a generally annular configuration;
• b. utilizing punch members to punch a plurality of holes in said material at predetermined fastening locations along a circumferential length of said material;
• c. clamping perimeter portions of the material that surrounds each of said holes between welding elements and welding mesh elements of said perimeter portions one to another to form relatively rigid perimeter portions that define the holes punched in the material;
• d. locating the wire mesh material at a mold location by means of locating pins extending through the holes in the wire mesh material, with circumferential edge portions of said material being positioned in structure defining inner and outer perimeter mold cavities;
• e. inserting a seal forming material into said inner and outer cavities, with said sealing material becoming impregnated in the edges of the wire mesh material;
• f. causing the seal forming material to harden, to form perimeter seal portions at the edges of the wire mesh material.