Composite Aircraft Joint

Abstract

A method and apparatus comprises a first number of layers of a composite material for a wing, a second number of layers of the composite material for the wing, and a metal layer located between the first number of layers and the second number of layers in the wing. The metal layer has a first thickness at a first area configured to receive a number of fasteners and a second thickness at a second area.

1 . An apparatus comprising:
 a first number of layers of a composite material for a wing;   a second number of layers of the composite material for the wing; and   a metal layer located between the first number of layers and the second number of layers in the wing, wherein the metal layer has a first thickness at a first area configured to receive a number of fasteners and a second thickness at a second area.   
     
     
         2 . The apparatus of  claim 1 , wherein the second area is configured to transfer loads carried by the metal layer to the first number of layers and the second number of layers in the second area. 
     
     
         3 . The apparatus of  claim 1 , wherein the metal layer changes in thickness by at least one of tapering from the first thickness to the second thickness and changing from the first thickness to the second thickness with a stair-step shape. 
     
     
         4 . The apparatus of  claim 1 , wherein the first number of layers, the second number of layers, and the metal layer extend to an edge of the wing configured to be attached to a fuselage of an aircraft in which the first area of the metal layer configured to receive the number of fasteners is at the edge of the wing. 
     
     
         5 . The apparatus of  claim 1 , wherein a portion of the metal layer extends beyond an edge for the first number of layers and the second number of layers, wherein the portion of the metal layer is configured for use in testing the metal layer with a selected load that is less than a maximum load expected during flight of an aircraft. 
     
     
         6 . The apparatus of  claim 1 , wherein the metal layer is comprised of a material selected from one of titanium, steel, and a metal alloy. 
     
     
         7 . The apparatus of  claim 1 , wherein the first number of layers and the second number of layers are configured to carry a load up to a maximum load expected during flight of an aircraft. 
     
     
         8 . The apparatus of  claim 7 , wherein the first number of layers, the second number of layers, and the metal layer are configured to carry a load greater than the maximum load expected during the flight of the aircraft. 
     
     
         9 . The apparatus of  claim 7 , wherein the load extends in a direction along a plane through the metal layer. 
     
     
         10 . The apparatus of  claim 1 , wherein the metal layer is bonded to the first number of layers and the second number of layers. 
     
     
         11 . The apparatus of  claim 1 , wherein the metal layer has a first side and a second side opposite to the first side and further comprising:
 a first layer of adhesive located on the first side of the metal layer, wherein the first number of layers is on the first layer of adhesive; and   a second layer of adhesive located on the second side of the metal layer, wherein the second number of layers is on the second layer of adhesive.   
     
     
         12 . An apparatus comprising:
 a number of layers of composite material for a first structure in which the number of layers of composite material extends to an edge of the first structure configured to be attached to a second structure; and   a metal layer bonded to the number of layers of composite material as part of the first structure, wherein the metal layer has a first thickness at a first area configured to receive a number of fasteners in the first area, and wherein the metal layer has a second thickness at a second area.   
     
     
         13 . The apparatus of  claim 12 , wherein the second area of the metal layer is configured to transfer loads carried by the metal layer to the number of layers of composite material. 
     
     
         14 . The apparatus of  claim 12 , wherein the metal layer changes in thickness by at least one of tapering from the first thickness to the second thickness and changing from the first thickness to the second thickness with a stair-step shape. 
     
     
         15 . The apparatus of  claim 12 , wherein the first structure is a skin panel for a wing and the second structure is a wing box in a fuselage of an aircraft. 
     
     
         16 . The apparatus of  claim 12 , wherein the metal layer is comprised of a material selected from one of titanium, steel, and a metal alloy. 
     
     
         17 . The apparatus of  claim 15 , wherein the number of layers of composite material is configured to carry a load up to a maximum load expected during flight of the aircraft. 
     
     
         18 . The apparatus of  claim 17 , wherein the number of layers of composite material and the metal layer are configured to carry a load greater than the maximum load expected during the flight of the aircraft. 
     
     
         19 . The apparatus of  claim 12 , wherein the first structure and the second structure are located in a platform selected from one of a mobile platform, a stationary platform, a land-based structure, an aquatic-based structure, a space-based structure, an aircraft, a surface ship, a tank, a personnel carrier, a train, a spacecraft, a space station, a satellite, a submarine, an automobile, a power plant, a bridge, a dam, a manufacturing facility, and a building. 
     
     
         20 . A method for manufacturing a wing of an aircraft, the method comprising:
 laying up a first number of layers of a composite material for the wing;   placing a metal layer on the first number of layers of the composite material, wherein the metal layer has a first thickness at a first area configured to receive a number of fasteners and a second thickness at a second area and wherein a first layer of adhesive material is on a first side of the metal layer and a second layer of the adhesive material is on a second side of the metal layer;   laying up a second number of layers of the composite material for the wing on top of the metal layer; and   bonding the first number of layers of the composite material, the metal layer, and the second number of layers of the composite material together.   
     
     
         21 . The method of  claim 20  further comprising:
 applying the first layer of the adhesive material to the first side of the metal layer prior to placing the metal layer on the first number of layers of the composite material; and 
 applying the second layer of the adhesive material to the second side of the metal layer. 
 
     
     
         22 . The method of  claim 20 , wherein the step of bonding the first number of layers of the composite material, the metal layer, and the second number of layers of the composite material comprises:
 curing the first number of layers of the composite material, the metal layer, and the second number of layers of the composite material.   
     
     
         23 . The method of  claim 20 , wherein the metal layer changes in thickness by at least one of tapering from the first thickness to the second thickness and changing from the first thickness to the second thickness with a stair-step shape. 
     
     
         24 . The method of  claim 20 , wherein the first number of layers, the second number of layers, and the metal layer are configured to carry a load greater than a maximum load expected during flight of the aircraft.