A minimally invasive surface attachment apparatus for non-penetrating mechanical attachment of components to a target surface includes a cartridge assembly and mounting assembly. Actuation of the cartridge assembly causes first and second exothermic reactants located between outer casing and the inner casing to come into contact and cause an exothermic reaction. This reaction liquefies a bonding material between the cartridge assembly and mounting assembly, allowing it to flow around the mounting assembly and onto a target surface creating a seal. Vacuum pressure will bind the mounting assembly to a target surface.

A patch may be used to rework a composite structure in the field. The patch is bonded to the structure by a layer of adhesive and includes perforations that allow the escape of air from the adhesive as the patch is compressed against the structure. A spacer may be introduced between the patch and the structure to control the thickness of the adhesive layer.