Adhesives are widely used throughout an aircraft. Jet engines contain structural adhesives, threadlockers, retaining compounds and thread sealants for hydraulic components. In the interior, epoxies, silicones and polyurethane foams are used to install floor lighting, assemble overhead bins and seat trays, and fill voids and seal the edges of honeycomb panels and carbon-fiber composite parts. In exterior applications, adhesives are used to bond stringers to wing skins and to seal doors, windows and fuselage components.
Ironically, however, aerospace assemblers have been slow to automate the process of dispensing adhesives and sealants.