Lining/fairing panel and method for measuring the electrical bonding resistance of a lining/fairing panel

Abstract

A lining/fairing panel, in particular a lining/fairing panel for an airborne vehicle such as an aircraft or a spacecraft is provided. The lining/fairing panel includes a panel body having a first surface and a second surface opposite to the first surface, an electrically conductive coating applied to the first surface or the second surface, and a via arranged in the panel body reaching from the first surface to the second surface of the panel body. The via is formed in an inner region of the panel body. The borders of the inner region are spaced apart by a predetermined distance from the borders of the first and second surface of the panel body.

What is claimed is: 
     
         1 . A method for measuring the electrical bonding resistance of a lining/fairing panel mounted on a structural element of an airborne vehicle,
 the lining/fairing panel comprising:   a panel body having a first surface and a second surface opposite to the first surface;   an electrically conductive coating applied to the first surface or the second surface; and   a via arranged in the panel body reaching from the first surface to the second surface of the panel body, the via being formed in an inner region of the panel body the borders of which inner region are spaced apart by a predetermined distance from the borders of the first and second surface of the panel body,   the method comprising the steps of:   forcing an electrical current through the bolt, the electrically conductive coating and the structural element;   measuring a voltage drop between the bolt and the structural element; and   determining the electrical bonding resistance of a lining/fairing panel dependent on the measured voltage drop.   
     
     
         2 . The method of  claim 1 , wherein the lining/fairing panel further comprises a bolt comprising an electrically conductive material arranged in the via, the bolt being electrically coupled to the electrically conductive coating. 
     
     
         3 . The method of  claim 2 , wherein the lining/fairing panel further comprises a nut arranged on the second surface of the panel body, wherein the bolt is a threaded bolt threadingly engaging the nut. 
     
     
         4 . The method of  claim 3 , wherein the lining/fairing panel further comprises a first washer comprising an electrically conductive material, the first washer being arranged between the nut and the second surface of the panel body. 
     
     
         5 . The method of  claim 1 , wherein the electrically conductive coating is applied to the second surface of the panel body, and wherein the first washer extends over at least part of the electrically conductive coating electrically coupling the electrically conductive coating to the bolt. 
     
     
         6 . The method of  claim 1 , wherein the lining/fairing panel further comprises a second washer comprising an electrically conductive material, the second washer being arranged between the bolt head and the first surface of the panel body. 
     
     
         7 . The method of  claim 6 , wherein the electrically conductive coating is applied to the first surface of the panel body, and wherein the second washer extends over at least part of the electrically conductive coating electrically coupling the electrically conductive coating to the bolt. 
     
     
         8 . The method of  claim 7 , wherein the second washer has a conical shape, and wherein the via comprises a conically shaped opening broadening towards the first surface configured to receive the second washer within the opening. 
     
     
         9 . The method of  claim 1 , wherein the panel body comprises a monolithic and electrically non-conductive glass fibre composite material. 
     
     
         10 . The method of  claim 1 , wherein the panel body comprises at least two layers of glass fibre composite material sandwiching a honeycomb core structure. 
     
     
         11 . The method of  claim 10 , wherein a filler of conductive or non-conductive material is arranged in the panel body surrounding the via. 
     
     
         12 . The method of  claim 1 , wherein the lining/fairing panel further comprises a surface protection layer applied to the electrically conductive coating.