Fastening system for aircraft structures
A fastening system to couple a first aircraft structure and a second aircraft structure is disclosed. The fastening system includes a fastener, a nutplate having a body defining an opening to receive the fastener, a flange extending from the body to engage an outer surface of the first structure, and a first sleeve protruding from the flange in a direction away from the body, the first sleeve to couple to a first bore formed in the first structure and prevents rotation of the nutplate relative to the first structure.
1 . A fastening system to couple a first structure and a second structure, the fastening system including:
a fastener having a threaded portion;
a nutplate having:
a body defining an opening to receive the fastener, the opening having internal threads to threadably receive the threaded portion of the fastener;
a flange extending from the body to engage an outer surface of the first structure;
a first sleeve protruding from the flange in a direction away from the body, the first sleeve to couple to a first bore formed in the first structure, the first sleeve, when positioned in the first bore, to prevent rotation of the nutplate relative to the first structure; and
a second sleeve insertable in a second bore formed in the second structure, wherein a first end of the first sleeve and a second end of the second sleeve opposing the first end of the first sleeve define a gap to enable the first end of the first sleeve to be spaced apart from the second end of the second sleeve when the first sleeve is coupled to the first bore and the second sleeve is coupled to the second bore, the gap to enable insertion of the first sleeve in the first bore and the second sleeve in the second bore without contact between the first sleeve and the second sleeve.
2 . The system of claim 1 , wherein the second sleeve couples to the second bore via a clearance fit.
3 . The system of claim 1 , wherein the first end of the first sleeve is oriented toward the second end of the second sleeve when the first sleeve is coupled to the first bore and the second sleeve is coupled to the second bore.
4 . The system of claim 3 , wherein the second end of second sleeve at least partially extends in the first bore of the first structure when the second sleeve is coupled to the second bore of the second structure.
5 . The system of claim 1 , wherein the first sleeve has a first outer diameter and the second sleeve has a second outer diameter, wherein the first outer diameter is substantially equal to the second outer diameter when the first sleeve is positioned in the first bore and the second sleeve is positioned in the second bore.
6 . The system of claim 5 , wherein the first sleeve defines a first inner diameter and the second sleeve defines a second inner diameter, wherein the first inner diameter is substantially equal to the second inner diameter when the first sleeve is positioned in the first bore and the second sleeve is positioned in the second bore.
7 . The system of claim 1 , wherein the first sleeve has a first outer diameter that is greater than a first inner diameter of the first bore prior to the first sleeve being coupled to the first bore.
8 . The system of claim 7 , wherein the first sleeve is coupled to the first bore via a press-fit connection to prevent rotation of the nutplate relative to the first structure.
9 . The system of claim 1 , wherein the first structure is a close-out panel of an aircraft and the second structure is a wingbox of an aircraft.
10 . The system of claim 1 , wherein the body includes a dome-shaped region.
11 . The system of claim 1 , further including a sealant positioned in the gap.
12 . The system of claim 1 , wherein the gap prevents the second sleeve from pushing the first sleeve out of the first bore when the second sleeve is positioned in the second bore.
13 . The system of claim 10 , wherein the internal threads are positioned between the flange and a tip of the dome-shaped region.
14 . The fastener assembly of claim 1 , wherein the gap between the first sleeve and the second sleeve is to at least one of prevent the first sleeve from moving the second sleeve out from the second bore when the first sleeve is inserted in the first bore or prevent the second sleeve from moving the first sleeve out from the first bore when the second sleeve is inserted in the second bore.