Abstract: The method comprises introducing a tip of a solid phase welding tool between adjacent surfaces of a crack formed in an aircraft skin. The tool is then operated to produce a friction stir weld so as to weld the adjacent surfaces together and thereby repair the crack. Apparatus for performing the method comprises a base having carriage thereon, the arm being pivotally mounted on the carriage and supporting the friction stir welding tool. The position of an arm can be adjusted by a screw which drives the rotating tip of friction stir welding tool into the crack to be repaired. The carriage is then moved along the base to draw the tip along the crack. The apparatus is portable and is particularly useful for repairing a cracked skin on an aircraft.

Abstract: The method comprises introducing a tip (40) of a solid phase welding tool (126) between adjacent surfaces of a crack (132) formed in an aircraft skin. The tool (126) is then operated to produce a friction stir weld so as to weld the adjacent surfaces together and thereby repair the crack (132). Apparatus for performing the method comprises a base (50) having carriage (55) thereon, the arm (76) being pivotally mounted on the carriage (55) and supporting the friction stir welding tool (126). The position of an arm (76) can be adjusted by a screw (94) which drives the rotating tip (40) of friction stir welding tool (126) into the crack (132) to be repaired. The carriage (55) is then moved along the base (50) to draw the tip (40) along the crack. The apparatus is portable and is particularly useful for repairing a cracked skin on an aircraft.