Method of joining panels for an airframe

A method of joining two panels of an airframe or fuselage structure of an aircraft or spacecraft, the method comprising:

• preparing a planar edge region of a first panel to form a first joining surface;
• preparing a planar edge region of a second panel to form a second joining surface, wherein the first panel is positioned on top of the second panel such that respective planar edge regions thereof overlie one another;
• wherein preparing the edge region of the first panel and preparing the edge region of the second panel comprises machining or cutting the planar edge regions of the first and second panels in a single operation to form the first and second joining surfaces substantially simultaneously, wherein a cutting tool extends through both of the panels into a backing material layer which supports the edge regions of the panels;
• aligning and positioning the first and second panels with respect to one another such that the first and second joining surfaces abut and interface in contact with one another to form a joint area, wherein the joining surfaces are substantially congruous or matching and make face-to-face contact in the joint area, and wherein the first and second joining surfaces are substantially planar and extend at an oblique angle with respect to a major plane or a major surface of the first and second panels;
• and
• joining the first and second panels at the joining surfaces in the joint area.